#*sv: shaven location: 4-3.0 [diplo-4 triploids (Sturtevant, 1951, Proc. Nat. Acad. Sci. USA 37: 405-7)]. origin: Spontaneous. discoverer: Bridges, 20k14. references: Morgan, Bridges, and Sturtevant, 1925, Bibliog. Genet. 2: 235 (fig.). Bridges, 1935, Biol. Zh. 4: 401-20. phenotype: Bristles reduced, somewhat variably. Trichogen irregularly displaced and usually partly converted to socket (Lees and Waddington, 1942, DIS 16: 70). sv/sv/sv triplo-4 nearly normal. sv haplo-4 extreme shaven (Schultz, 1935, Am. Naturalist 69: 30-54). Expression depends on temperature: excellent at 19, overlaps wild type at 25, and entirely wild type at 30. RK2. cytology: Placed in region between 102E2 and 102F10 on the basis of its inclusion in Df(4)11 = Df(4)102E2-10;102F2-10. # sv2: see svn # sv35a discoverer: Ives, 35a18. references: 1935, DIS 4: 11. phenotype: Resembles svn more than sv. Bristles frequently reduced to stumps. RK2. svde: shaven-depilate Edith M. Wallace, unpublished. # svde: shaven-depilate origin: Spontaneous. discoverer: E.M. Wallace, 37a24. phenotype: More extreme than svn. Thorax denuded over large areas. Phenotype more severe than H2; bristleless sockets found on adult integumentary derivatives of all imaginal discs; nearly 100% penetrance on thorax. Shafts, where present, often bent, twisted, or forked; up to 97% of bristle organs on wing costa and distal leg segments fail to produce normal shafts. Bracts present when bristle normally formed; otherwise bracts missing (Tobler, Rothenbuhler, and Nothiger, 1973, Experientia 29: 370-71). Both sexes sterile. RK2. # svn: shaven-naked discoverer: Mohr, 31j13. synonym: sv2. references: 1933, Hereditas 17: 317-22 (fig.). phenotype: Extremely short bristles. Viability excellent. Trichogen irregularly displaced, becoming more or less con- verted into tormogen [Lees and Waddington, 1943, Proc. Roy. Soc. (London), Ser. B, 131: 87-110 (fig.)]. Polarity of microchaetae in vicinity of double sockets disrupted such that they form a whorl around socket [Toney and Thompson, 1980, Experientia 36: 644-45 (fig.)]. In triplo-4 svn/svn/svn, the phenotype is more nearly normal than in diplo-4. RK1. other information: Selective advantage for triplo-4 in stocks of svn results in accumulation. # svb: shaven baby location: 1-9.8. references: Wieschaus, Nusslein-Volhard, and Jurgens, 1984, Wilhelm Roux's Arch. Dev. Biol. 193: 296-307. Gergen and Wieschaus, 1985, Dev. Biol. 109: 321-35 (fig.). phenotype: Homozygous lethal. Many fewer denticles than wild type; remaining denticles small and with characteristic mor- phology. Denticles arranged in belts in the abdominal seg- ments; absent from thoracic segments. Cell autonomous in mosaics; useful in studying embryonic mosaics. alleles: allele origin synonym ref ( comments __________________________________________________________ svb1 EMS svbYD39 3 polyphasic, ovo- svb2 EMS svbYP17b 2, 3 polyphasic, ovo+, no maternal effect svb3 EMS svbEH587 1 polyphasic, ovo- hnt+ ( 1 = Eberl and Hilliker, 1988, Genetics 118: 109-20; 2 = Perrimon, Engstrom, and Mahowald, 1989, Genetics 121: 333-52; 3 = Wieschaus, Nusslein-Volhard, and Jurgens, 1984, Wilhelm Roux's Arch. Dev. Biol. 193: 296-307. cytology: Placed in 4E1-2 along with ovo based on the simul- taneous loss of both functions in many ovoD reversions. Included in Df(1)bi-DL5 = Df(1)3C7-12;4E1-2 and Df(1)bi-D2 = Df(1)4B6-C1;4D7-E1, both of which retain ovo+ (Oliver, Perri- mon, and Mahowald, Genes Dev. 1: 913-23). # svp: seven up (Y. Hiromi) location: 3- {52}. references: Gausz, Gyurkovics, Bencze, Awad, Holden, and Ish- Horowicz, 1981, Genetics 98: 775-89. Mlodzik, Hiromi, Weber, Goodman, and Rubin, 1990, Cell 60: 211-24. phenotype: Originally identified as recessive lethal mutations; independently identified by an enhancer-trap screen to be a gene expressed in a subset of neuroblasts in the embryonic CNS and also in a subset of photoreceptor-cell precursors in the developing compound eye. Mutant alleles die as embryos with normal cuticular morphology, but have alterations in numbers of eve-positive neurons in some neuroblast lineages. svp- clones in the eye produce abnormal ommatidia where photorecep- tors R1, R3, R4, and R6 are transformed toward another pho- toreceptor R7. In addition, svp- ommatidia usually contain one to two extra photoreceptor cells. Mosaic studies show that transformation towards R7 is due to cell autonomous requirement in R1, R3, R4, and R6, whereas production of extra cell(s) is a secondary phenotype caused by lack of svp+ func- tion in other cells, most likely in R3 and R4. Formation of some, but not all, R7-like cells in svp- ommatidia is depen- dent on sev+ function. alleles: Of eight ethyl methanesulfonate-induced alleles listed by Gausz et al., only two are now existent (svp1 and svp2); svp3 has an enhancer trap P-element insertion at the svp locus and expresses |-galactosidase in a pattern resembling the svp transcription pattern. allele synonym comments ____________________________________________ svp1 l(3)ck16e22 embryonic lethal svp2 l(3)ck16e300 embryonic lethal svp3 svpH162 embryonic lethal cytology: Placed in 87B4-6 based on its inclusion in the region of overlap of Df(3R)T45 = Df(3R)86E;87B5-6 and Df(3R)kar-H10 = Df(3R)87B4;87D7-8. molecular biology: Walking from the enhancer trap P-element insert, a transcription unit was identified whose expression pattern is indistinguishable from the |-galactosidase expres- sion pattern of the P-insertion allele. The conceptual amino-acid sequence from a svp cDNA clone shows that svp is a member of the steroid receptor gene superfamily, and is likely to be the Drosophila homologue of the human transcription fac- tor COUP. # svr: silver location: 1-0.0. discoverer: Bridges, 23g23. synonym: slv. references: Morgan, Bridges, and Sturtevant, 1925, Bibliog. Genet. 2: 235. Morgan, 1940, DIS 13: 51. phenotype: Color of legs, wings, veins, and integument pale and silvery. Bristles and trident pattern on thorax dark. Tyro- sinase formed in adult (Horowitz). Wings of all males and some females pointed. Viability fair. Larval mouth parts normal in color. RK2. alleles: allele origin discoverer synonym ref ( comments _______________________________________________________________________ svr1 Bridges, 23g23 svr2 EMS Lim svr016 svr3 EMS Lim svr121 svr4 MMS Lim svrM9 *svr5 MMS Lim svrM14 *svr6 X ray Lefevre l(1)C235 6 svr7 X ray Lefevre l(1)RA61 6 svr8 EMS Lefevre l(1)DC765 7, 8 larval; no maternal effect svr9 EMS White svr10 EMS White svr11 EMS White svr12 EMS White svr13 EMS White svr14 EMS White svr15 EMS White svr16 EMS White svr17 ENU Voelker l(1)A41 svr18 ENU Voelker l(1)A71 svr19 ENU Voelker l(1)A106 svr20 ENU Voelker l(1)A122 *svrpoi spont Goldschmidt, poi 1, 2, pointed wings 1934 3, 5 *svrpoi-bl spont Goldschmidt 1, 3 pointed blis- tered wings *svrpoi-Ca spont Goldschmidt 1, 3 pointed from Canton S svrpoi-dish spont Goldschmidt 1, 3, 5 dishevelled microchaetae *svrpoi-h spont Goldschmidt 1 *svrpoi-ll spont Goldschmidt 1, 4 lanceolate wings *svrpoi-s spont Goldschmidt 1, 3 wing tips pointed, narrow *svrpoi-si spont Goldschmidt 1, 3 pointed wings *svrpoi-sq spont Goldschmidt 1, 3 pointed, blis- tered wings *svrPoi spont Goldschmidt 1, 4 pointed wings, dominant *svrPoi-s spont Goldschmidt 1, 4 semidominant svrts1 EMS White svrts2 ENU Voelker l(1)A95 svrts3 ENU Voelker l(1)A104 ( 1 = CP 627; 2 = Goldschmidt, 1944, DIS 18: 42; 3 = Goldsch- midt, 1945, Univ. Calif. (Berkeley) Publ. Zool. 49: 291- 550; 4 = Goldschmidt, 1947, J. Exp. Zool. 104: 197-222; 5 = Goldschmidt and Hannah, 1944, Proc. Nat. Acad. Sci. USA 30: 299-301; 6 = Lefevre, 1981, Genetics 99: 461-80; 7 = Lefevre and Watkins, 1986, Genetics 113: 869-95; 8 = Perrimon, Engstrom, and Mahowald, 1989, Genetics 121: 333-52. cytology: Locus placed at 1B5-6 (Demerec, Kaufmann, Fano, Sut- ton, and Sansome, 1942, Year Book - Carnegie Inst. Washington 41: 191). other information: Pointed alleles studied by Goldschmidt enhanced by aba. svrpoi and svrpoi-dish reported to suppress s and sp. #*svs: shortened veins location: 1-24.6. origin: Induced by ethyl methanesulfonate (CB. 1528). discoverer: Fahmy, 1956. synonym: shv (preoccupied). references: 1959, DIS 33: 90. phenotype: Wings highly abnormal, varying from small stubs to almost full size with inner margin cut away. Vein L4 often shortened and posterior crossvein absent. Eyes small and deformed. Male fertile; viability about 50% wild type. Female sterile. RK2. sw: short wing From Eker, 1935, J. Genet. 30: 357-68. # sw: short wing location: 1-64.0 (to the left of mel). discoverer: Eker, 32a12. references: 1935, J. Genet. 30: 357-68 (fig.). 1939, J. Genet. 38: 201-27. phenotype: Above 23, most sw1 flies have spread and incised wings with irregular veins; eyes reduced and roughened. Male expression more extreme than female. 15% of males eclose at 25; show wing and eye abnormalities (Schalet, 1969, DIS 43: 128); above 31, sw is lethal. At 17, most flies are wild type; at 14, all are wild type. +/Df(1)mal10 and +/sw exhibit short-wing phenotype in presence of RpII215Ubl (Mortin and Lefevre, 1981, Chromosoma 82: 237-47). RK2 at 28. alleles: Either this is a complex locus with sw4 being the only noncomplementing allele or sw4 is a double mutant and there are two loci. Numerous lethal alleles at this locus recovered from line containing a P element in 19C (Simmons, Raymond, Johnson, and Fahey, 1984, Genetics 106: 85-94). allele origin discoverer synonym ref ( comments ________________________________________________________________________ sw1 Eker, 32a12 1, 2 sw2 X ray Lefevre l(1)GA80 4 lethal with sw1 sw3 X ray Lefevre l(1)HC274 4 complements sw1 sw4 X ray Lefevre l(1)HC326 4 noncomplementing sw5 EMS Lefevre l(1)DA648 5 lethal with sw1 sw6 EMS Lefevre l(1)VA172 5 lethal with sw1 sw7 EMS Lefevre l(1)VA214 5 lethal with sw1 sw8 EMS Baldwin l(1)LB11 6 sw9 EMS Lefevre l(1)EF401 5 complements sw1 sw10 EMS Lefevre l(1)VA125 5 complements sw1 sw11 EMS Lefevre l(1)VA138 5 complements sw1 sw12 EMS Lefevre l(1)VA271 5 complements sw1 sw13 EMS Lefevre l(1)VA310 5 complements sw1 sw14 neutron Munoz l(1)17-234 6 sw14/sw1 wild type at 25; sw at 29 sw15 spont Schalet swl-S1M early pupal lethal with sw1 *sw16 spont Lee "short wing" 3 wings with curled edges, broad tips, broken veins; female sterile; allelism tentative ( 1 = Eker, 1935, J. Genet. 30: 357-68 (fig.); 2 = Eker, 1939, J. Genet. 38: 210-27; 3 = Lee, 1972, DIS 48: 18; 4 = Lefevre, 1981, Genetics 99: 461-80; 5 = Lefevre and Wat- kins, 1986, Genetics 113: 869-95; 6 = Schalet and Lefevre, 1976, The Genetics and Biology of Drosophila (Ashburner and Novitski, eds.). Academic Press, London, New York, San Fran- cisco, Vol. 1b, pp. 847-902. cytology: Placed in 19B3-C4 based on its inclusion in Df(1)T2- 4A = Df(1)19B3;19C4. # swy: see stw2 # swa: see crmswa # swa: swallow location: 1-15.9 (between rux and shf). synonym: sww. references: Zalokar, Audit, and Erk, 1975, Dev. Biol. 47: 419-32. Fronhofer and Nusslein-Volhard, 1987, Genes Dev. 1: 880-90. phenotype: Maternal-effect lethal; homozygous females sterile. Some blastoderms irregularly populated, with some areas on surface devoid of nuclei, others display asynchronous nuclear divisions and nuclei of non uniform size. Gastrulation occurs before full complement of nuclei achieved; mitosis continues into gastrulation. Developmental arrest at time of first mus- cular activity. In swa2 development normal but abnormal lar- val mouth parts prevent feeding. Mosaic studies with swa1 indicate that the gene functions in germ line (Perrimon and Gans, 1981, Dev. Biol. 100: 365-73). Morphology of develop- ing embryos shows variable temperature-sensitive failure of head-segment development and abdominal segmentation defects. Anterior defects more severe at 29, and posterior ones cold sensitive, strongly enhanced at 18. ftz expression pattern abnormal; number of stripes varies from three (PS 2, 4, & 6) at 18 to seven at 29. Unlike wild-type cytoplasm, anterior cytoplasm from embryos of swa mothers ineffective in rescuing bcd phenotype; also embryos from swa females resistant to the bcd-phenocopying effects of removing anterior cytoplasm (Fronhofer and Nusslein-Volhard). alleles: allele origin discoverer synonym ref ( comments _____________________________________________________________ swa1 EMS Gans fs(1)1497 1, 5 strong allele swa2 EMS Gans fs(1)1502 1, 5 weak allele swa3 EMS Mohler fs(1)11-999 2, 3 strong allele swa4 EMS Mohler fs(1)13C82 2, 3 strong allele swa5 EMS Stephenson fs(1)T573 3 weak allele swa6 EMS fs(1)384 4 ( 1 = Gans, Audit, and Masson, 1975, Genetics 81: 683-704; 2 = Mohler, 1977, Genetics 85: 259-72; 3 = Mohler and Car- roll, 1984, DIS 60: 236-41; 4 = Stephenson and Mahowald, 1987, Dev. Biol. 124: 1-8; 5 = Zalokar, Audit, and Erk, 1975, Dev. Biol. 47: 419-32. cytology: Placed in 5E6-7 based on in situ hybridization to a normal X chromosome but not to Df(1)JF5 = Df(1)5E5-6;5E7-8 (Stephenson and Mahowald). molecular biology: Gene cloned and restriction mapped; identity confirmed by rescue of swa by transformation. Detects a 2.1 kb transcript on Northern blots whose expression is restricted to the nurse cells. The message is uniformly distributed in the mature oocyte, becoming more concentrated peripherally at blastoderm formation, and disappearing by the time of gastru- lation. The anterior localization of bcd+ product disrupted in the oocytes of homozygous swa females (Stephenson, Chao, and Fackenthal, 1988, Genes Dev. 2: 1655-65). # swarthy: see swy # swb: see faswb listed under N # swi: see hfw # swiss cheese: see sws # swollen antenna: see crmswa # sws: swiss cheese (J.C. Hall) location: 1-22. origin: Induced by ethyl methanesulfonate. discoverer: Heisenberg. phenotype: Isolated in anatomical screen (cf. Heisenberg and Bohl, 1979, Z. Naturforsch. 34: 143-47); many Swiss-cheese- like holes seen in brain sections of adults (similar to pheno- type observed in dying drd flies). alleles: Three alleles, sws1, sws2, and sws3, with isolation numbers HK151, KS43, and RH7, respectively. other information: Phenotype has become less extreme, apparently due to accumulation of modifiers (Heisenberg). #*swy: swarthy location: 1-42.5. origin: Induced by 2-chloroethyl methanesulfonate (CB. 1506). discoverer: Fahmy, 1956. references: 1959, DIS 33: 92. phenotype: Body color slightly dark; darkened scutellum partic- ularly noticeable. Eyes brownish (best detected immediately after eclosion) and occasionally misshapen. swy/s is wild type. Viability about 50% wild type. Both sexes fertile. RK2. # sx: sexcombless location: 1- (rearrangement). origin: X ray induced. discoverer: Muller, 26l. references: Mukherjee, 1965, Genetics 51: 285-304 (fig.). Reinhard and Sanchez, 1982, Wilhelm Roux's Arch. Dev. Biol. 191: 264-69 (fig.). phenotype: Number of teeth in primary sex comb reduced from the normal 10 to 1. Bristles intermediate between normal bristles and sex-comb teeth also appear in sex-comb area. Bristle pat- tern of sx male basitarsus feminized in other respects. sx/+ reduces the mean number of sex-comb teeth in tra/tra female from 11.37 to 3.7. Sex-comb development autonomous in mosaic from either chromosome loss or somatic crossing over in tra/tra female (Mukherjee and Stern, 1965, Z. Indukt. Abstamm. Vererbungsl. 96: 36-48). Reduces number of teeth in secon- dary sex comb of en/en male and in primary sex comb of eyD/+ male. Homozygous females generated from homozygous mei-332 mothers have normal leg chaetotaxy (Reinhard and Sanchez). Male sterile owing to imperfect development of internal duct system; testes often remain unattached to ducts, and are therefore ellipsoidal, but contain fully developed sperm (Stern, 1941, J. Exp. Zool. 87: 113-58). External genitalia also greatly modified. Size, shape, and arrangement of teeth on clasper varies; occasionally more than one penal apparatus (Mukherjee). Structures frequently missing and usually displays bilateral asymmetry; also extra and missing bristles. Homozygous females characteristically lack vulva; thorn bris- tles on vaginal plate often present as a double row; internal genitalia absent; ovaries small but normal in shape; anal plates reduced or absent (Reinhard and Sanchez). RK2A. cytology: Associated with In(1)sx = In(1)11D4-6;11E2-6;14B8- 9;15E2-4 (Mukherjee, 1963, DIS 38: 62). # sxc: super sex combs (P.W. Ingham) location: 2-55.3 (0.8 unit to the right of pr). references: Ingham, 1984, Cell 37: 815-23. phenotype: Homozygous adults exhibit homeotic transformation of antenna to first leg, of second and third legs to first leg, of wing to haltere, and of abdominal segments A1, A4, and A5 to A2, A5, and A6, respectively. Homozygotes derived from homozygous female germ line exhibit transformation of larval thoracic and abdominal segments toward A8. alleles: allele origin discoverer comments ____________________________________________________ sxc1 EMS Ingham sxc2 X ray Ingham T(2;3)41C1-2;98C ;99A sxc3 EMS Ingham sxc4 EMS Ingham sxc5 EMS Ingham cytology: Placed in 41C1-2 based on the breakpoint of T(2;3)sxc2 and on its inclusion in Df(2R)M41A4, which, although cytologically invisible, is deficient for M(2)41A, at the base of 2R. # Sxl: Sex lethal (T.W. Cline) location: 1-19.2. synonym: Fl: Female lethal; Su(da). references: Muller and Zimmering, 1960, Genetics 45: 1001-02. Zimmering and Muller, 1961, DIS 35: 103-04. Marshall and Whittle, 1978, Genet. Res. 32: 103-11. Cline, 1978, Genetics 90: 683-97. 1979a, Dev. Biol. 72: 266-75. 1979b, Genetics 93: 681-701. 1980, Genetics 96: 903-26. Lucchesi and Skripsky, 1981, Chromosoma 88: 217-27. Skripsky and Lucchesi, 1982, Dev. Biol. 94: 153-62. Uenoyama, 1982, Jpn. J. Genet. 59: 335-48. Sanchez and Nothiger, 1982, Wilhelm Roux's Arch. 191: 211-14. Cline, 1983, Dev. Biol. 95: 260-74. Sanchez and Nothiger, 1983, EMBO J. 2: 485-91. Cline, 1984, Genetics 107: 231-77. Maine, Salz, Cline, and Schedl, 1985a, Cell 43: 521-29. Maine, Salz, Schedl, and Cline, 1985b, CSHSQB 50: 595-604. Schupbach, 1985, Genetics 109: 529-48. Cline, 1986, Genetics 113: 641-63; corregendum 114: 345. Salz, Cline, and Schedl, 1987, Genetics 117: 221-31. Gergen, 1987, Genetics 117: 477-85. Bell, Maine, Schedl, and Cline, 1988, Cell 55: 1037-46. Cline, 1988, Genetics 119: 829-62. Oliver, Perrimon, and Mahowald, 1988, Genetics 120: 159-71. Steinmann-Zwicky, 1988, EMBO J. 7: 3889-98. Steinmann-Zwicky, Schmid, and Nothiger, 1989, Cell 57: 157- 66. Salz, Maine, Keyes, Samuels, Cline, and Schedl, 1989, Genes Dev. 3: 708-19. Steinmann-Zwicky, Schmid, and Nothiger, 1989, Cell 57: 157- 66. Tompkins and McRobert, 1989, Genetics 123: 535-41. phenotype: Sxl+ is a switch gene that acts throughout develop- ment to control all aspects of sexual dimorphism. Its pro- ducts are required for female and must be absent for male development. Uniquely among sex-determination genes, after responding early in development to the primary sex- determination signal (the X:A ratio), Sxl maintains its own activity state as well as that of the downstream genes with which it interacts. It is required in a cell-autonomous fashion for both germ-line and somatic female development. It controls dosage compensation in females by suppressing hyperactivation of X-linked genes. Mutations of Sxl fall into two general classes: (1) recessive loss-of-function alleles that are deleterious to homozygous females, but viable and without phenotypic consequences in males, and (2) dominant gain-of-function alleles that behave as constitutive muta- tions, dominant and deleterious in males but without adverse effect in females, either heterozygous or homozygous. The variety of functions of the Sxl gene can be affected differen- tially by mutations, accounting in part for the complex com- plementation pattern observed for the large array of diverse mutant alleles. It is important to be aware that phenotypic parameters of mutant alleles and allele combinations can be very sensitive to culture conditions and genetic background. A number of positive regulators of Sxl are known, including the genes da, fs(1)A1621, sis-a, and sis-b. The female- specific lethal or sterile effects of mutations in these genes are suppressed by gain-of-function Sxl alleles. Throughout all but the very earliest period of development, female- specific expression of Sxl is known to be achieved by female- specific splicing of mRNA. The translation products from these female-spliced RNAs appear to help maintain the female- specific (productive) RNA processing mode which generates them, thereby establishing a positive feedback loop that main- tains the female state throughout development. alleles: The current convention for this gene is that alleles specifically disrupting female development (generally reces- sive loss of function) are designated Sxlf, followed by a number, whereas those specifically disrupting male development (generally dominant gain of function) are designated SxlM, followed by a number. In cases where a single lesion might have both characters, the SxlM designation would prevail. P in the designation indicates that the allele (and sometimes the stock as well) is likely to harbor P-element sequences. For new alleles selected as changes in the functioning of pre-existing mutant alleles, the original allele designation is followed by a d (for "derivative"), then a number. If and when such derivatives are shown to carry more than one lesion within the gene, the mutant designation will change to reflect the presence and order on the chromosome of the multiple lesions, individual mutations being separated by commas. For the most part, alleles in common use before these conventions were adopted were renamed only if the changes were relatively minor and self evident. allele origin synonym ref ( comments ___________________________________________________________________________ Sxlf1 spont Fl 4, 5, 9, 12, cannonical amorph 17, 21, 23, 24, 25, 26, 28, 29 Sxlf2 spont Fls, Sxlfs 11, 12, 14, 16 hypomorph, escapers female but sterile; 5 kb insert present Sxlf4 EMS fs(1)M1061 15, 18, 19 fully viable; female sterile Sxlf5 EMS fs(1)M1062 15, 18 fully viable; female sterile Sxlf6 EMS In(1)Sxl-af 12 null; associated with 6F; breakpoint Sxlf7,M1 / ray Sxlfm7,M1 5, 6, 7, 19, male-viable, female- 23, 25 semilethal, double- mutant derivative of SxlM1; escaper females masculinized Sxlf9 EMS 6, 13, 19 hypomorph; provides later functions best Sxlf2593 EMS Sxl2593 5, 13, 19 hypomorph; ts for variety of functions; escapers masculinized to variable degree Sxlfhv1 spont 3, 6, 11, 12 hypomorph; females viable and fertile; ca 6 kb insert present SxlfLS spont 6, 12, 13, 19, hypomorph; provides 21, 22 early functions best; gypsy insert present SxlfP3G2 HD Sxlf3G2 19, 20 male-viable null deletion of ca 22 kb from SxlfPb SxlfP6C2 HD Sxlf6C2 19 male-viable null deletion from SxlfPb SxlfP7A1 HD Sxlf7A1 19 male-viable hypo- morph; intragenic deletion within SxlfPb SxlfP7AV HD Sxlf7AV 19 male-viable hypo- morph; intragenic deletion within SxlfPb SxlfP7B0 HD Sxlf7BO 19, 20, 27 male-viable null; deletion of >50 kb; deletion from SxlfPb SxlfP7C2 HD Sxlf7C2 19 male-viable null; deletion from SxlfPb SxlfPb spont 10, 12, 13, 19 hypomorph due to P element insertion; mosaic intersex female clones SxlfPED1 HD SxlfED1 19, 20 male-viable null; deletion of >28 kb; deletion from SxlfPb SxlfPED2 HD SxlfED2 19 male-viable null; deletion from SxlfPb SxlfPODH HD SxlfODH 19 male-viable hypo- morph; intragenic deletion within SxlfPb SxlfPRC1 HD SxlfRC1 19 Sxl hypomorph; l(1)7Aa deletion extending proximally from SxlfPb SxlfPRJ2 HD SxlfRJ2 19 Sxl hypomorph; l(1)7Aa deletion extending proximally from SxlfPb SxlfPRL2 HD SxlfRL2 19 Sxl hypomorph; l(1)7Aa deletion extending proximally from SxlfPb SxlM1 spont 1, 2, 3, 4, 5, partially constitutive 9, 10, 11, 26 due to roo insert near male-specific exon SxlM1,f3 / ray SxlM1,fm3 5, 25 male-viable, female- lethal, double- mutant derivative of SxlM1; escaper females SxlM1,fPa HD 12, 13 double mutant; apparent null due to P-element insertion into SxlM1 SxlM1,fPa-ra HD 8, 13, 27 complex partial revertant of SxlM1,fPa com- plementing Sxlf9; male ts; female cs SxlM1-vdl spont 12 return of wild-type function by partial deletion of SxlM1 insert SxlM2 spont 12 similar to SxlM1 at molecular level SxlM3 spont 12 ca 5 kb hobo | insert near male- specific exon 3 SxlM4 spont 12 ca 2 kb insert near male-specific exon 3 SxlM5 spont 12 similar to SxlM3 at molecular level ( 1 = Cline, 1978, Genetics 90: 683-97; 2 = Cline, 1979, Dev. Biol. 72: 266-75; 3 = Cline, 1980, Genetics 96: 903-26; 4 = Cline, 1983, Dev. Biol. 95: 260-74; 5 = Cline, 1984, Genetics 107: 231-77; 6 = Cline, 1986, Genetics 113: 641- 63, corregendum 114: 345; 7 = Cline, 1988, Genetics 119: 829-62; 8 = Cline, 1989, in Evolutionary Mechanisms in Sex Determination (Wachtel, ed.). CRC Press, pp. 23-36; 9 = Gergen, 1987, Genetics 117: 477-85; 10 = Golubovsky, 1983, DIS 59: 42-43; 11 = Lucchesi and Skripsky, 1981, Chromosoma 88: 217-27; 12 = Maine, Salz, Cline, and Schedl, 1985, Cell 43: 521-29; 13 = Maine, Salz, Schedl, Cline, 1985, Cold Spring Harbor Symp. Quant. Biol. 50: 595-604; 14 = Marshall and Whittle, 1978, Genet. Res. 32: 103-11; 15 = Mohler and Carroll, 1984, DIS 60: 236-41; 16 = Muller and Zimmering, 1960, Genetics 45: 1001-02; 17 = Oliver, Perrimon, and Mahowald, 1988, Genetics 120: 159-71; 18 = Perrimon, Mohler, Engstrom, and Mahowald, 1986, Genet- ics 113: 695-712; 19 = Salz, Cline, and Schedl, 1987, Genetics 117: 221-31; 20 = Salz, Maine, Keyes, Samuels, Cline, and Schedl, 1989, Genes Dev. 3: 708-19; 21 = Sanchez and Nothiger, 1982, Wilhelm Roux's Arch. Dev. Biol. 191: 211-14; 22 = Sanchez and Nothiger, 1983, EMBO J. 2: 485-91; 23 = Schupbach, 1985, Genetics 109: 529-48; 24 = Skripsky and Lucchesi, 1982, Dev. Biol. 94: 153-62; 25 = Steinmann-Zwicky, 1988, EMBO J. 7: 3889-98; 26 = Steinmann-Zwicky, Schmid, and Nothiger, 1989, Cell 57: 157-66; 27 = Tompkins and McRobert, 1989, Genetics 123: 335-41; 28 = Uenoyama, 1982, Jpn. J. Genet. 59: 335- 48; 29 = Zimmering and Muller, 1961, DIS 35: 103-04. | Shown to be a hobo element (Bernstein, 1989) rather than 297 as originally reported. cytology: Placed in 6F4-7B3 (Nicklas and Cline, 1983, Genetics 103: 617-31) based on its inclusion in Df(1)Sxl-ra = Df(1)6F4-5;7B1-3 (Lim). molecular biology: The genomic region cloned by transposon tag- ging from SxlfPb; ca 50 kb walk restriction mapped and mutant alleles characterized over a 26 kb region between coordinates -13 and +13 (coordinate 0 corresponds to the site of insertion of the P element in SxlfPb)(Maine et al., 1985; Salz et al., 1989). Northern blot analysis reveals ten different Sxl tran- scripts derived from a 23 kb region, coordinates +1 to -22. All have closely related structures and are transcribed in the same (increasing negative coordinate) direction (Salz et al., 1989). Three transcripts of 4.0, 3.1, and 1.7 kb appear tran- siently in blastoderm embryos. All others appear in later embryogenesis and persist throughout the remainder of develop- ment. Adult females have four Sxl transcripts of 4.2, 3.3, 3.3, and 1.9 kb; one 3.3 and the 1.9 kb species are reduced or absent in adults lacking a functional germ line. Adult males produce transcripts of 4.4, 3.6, and 2.0 kb. Two cDNAs, one from adult males and one from adult females derived from the 5' 15 kb of the Sxl transcription unit were sequenced (Bell et al., 1988); the correspondence to the mRNAs is not known. The amino acid sequence inferred from the female cDNA predicts a 354 amino-acid protein of 39,000 daltons; the sequence indi- cates a basic protein which by hydropathy analysis has charac- teristics of a soluble protein; it contains duplicated domains of 74 residues each, one at 126-199 and the other at 212-285, which exhibit 35% identity and show sequence similarity to known RNA-binding proteins (Bell et al.). Eight exons have been identified so far, with translation initiation likely from exon 2; exon 3 is found only in the three male specific transcripts, which otherwise correspond closely to three female-specific transcripts. Males are the sex in which genetic analysis shows Sxl to be nonfunctional. This exon contains two in-frame stop codons that would abort translation early on. Thus for most of development the on/off regulation of Sxl involves alternative modes of RNA processing. Con- sidered in light of the genetic evidence for positive autore- gulation of Sxl independent of the primary sex-determination signals (Cline, 1984, 1989), it would appear that Sxl main- tains the female developmental state by controlling its own RNA splicing (Bell et al.). The predicted amino-acid sequence of Sxl products is consistent with this idea. Since Sxl is known to be required for sex-specific splicing of more developmentally specialized genes such as tra (Nagoshi, McKeown, Burtis, Belote, and Baker, 1988, Cell 53: 229-36), it appears that the biochemical activities of Sxl that main- tain the sexually determined state may be the same as those that direct sexual differentiation through the regulation of genes downstream. Characteristics of the transcription pat- tern very early in development suggest that a different mode of regulation operates during this period when the gene is first responding to the primary sex-determination signal to set the sexual fate of cells (Salz et al., 1989). Genetic (Salz et al., 1987) and molecular (Salz et al., 1989) studies suggest that the promoter operating during this early period is different from that which functions throughout the remainder of development, when sex-specific activity is deter- mined by RNA splicing. # Sxlf1 phenotype: Homozygous females invariably die as embryos but hemizygous males are fully viable and fertile. In most wild- type genetic backgrounds, heterozygous females exhibit normal viability and fertility, although occasionally display morpho- logical defects characteristic of early cell death; however, can be dominant semilethal for females in some wild-type genetic backgrounds and under suboptimal growth conditions. In doubly heterozygous combination with otherwise recessive mutations in positive regulators of Sxl, this allele can behave as a dominant: heterozygote viability is reduced for daughters of da/+ females, as well as for females that are also heterozygotes for either sis-a, sis-b or fs(1)A1621. In some such doubly heterozygous situations, escaper females may be incompletely masculinized (mosaic intersex). Homozygosity for mutations in the autosomal male-specific lethal loci does not suppress recessive Sxlf1 lethality, but it does partially masculinize Sxlf1/+ females (generating mosaic intersexes) and suppresses cell-death-related morphological defects. Homozy- gous moribund embryos show sex-specific alterations in the phenotypic expression of hypomorphic X-linked alleles such as run25, a reflection of upsets in dosage compensation (female hyperactivation). Depending on the time of induction, Sxlf1/Sxlf1 clones induced in Sxlf1/+ females can be phenotyp- ically male and reduced in size. 2X:3A animals homozygous or heterozygous for Sxlf1 are viable but masculinized. In genetic mosaics and chimeras, Sxlf1 homozygous germ cells develop abnormally and fail to generate functional gametes. In some situations, the mutant female tissue displays mascu- line traits. Sxlf1 rescues males from the otherwise lethal effects of a simultaneous duplication of sis-a+ and sis-b+. # Sxlf2 phenotype: Homozygous females are either inviable or very poorly viable, depending on genetic background. Escapers are invariably sterile but otherwise display no obvious sexual abnormalities. Complements Sxlf2593. Homozygotes defective in dosage compensation as indicated by hyperincorporation of uridine by their polytene chromosomes. Allele fails to sup- port oogenesis in germ-line clones induced by mitotic recombi- nation. # Sxlf3 phenotype: A hypomorphic allele selected as an intragenic suppressor of SxlM1 male lethality; maps 0.0065 cM to the right of SxlM1. Only characterized in cis combination with SxlM1. The double mutant is fully viable in males and poorly viable in homozygous females, with escapers being phenotypi- cally male and sterile. Hemizygous females are lethal. Par- tially complements Sxlf2593, generating true intersexes. Par- tially complements Sxlf7,M1 with escapers phenotypically male and sterile. Fully complements Sxlfhv1. By itself, double mutant fails to bypass maternal da+ requirement for activa- tion, but can complement Sxlf7,M1 in this regard. Double heterozygote with fs(1)A1621 is fertile. # Sxlf7 phenotype: A hypomorphic allele selected as an intragenic suppressor of SxlM1 male lethality; maps 0.0099 cM to the left of SxlM1. Only characterized in cis combination with SxlM1. The double mutant is male viable and semiviable in homozygous females. Escaper females are phenotypically male and sterile. Hemizygous females are inviable. Double heterozygote with fs(1)A1621 is sterile, like Sxlf1 but unlike SxlM1,f3. The double-mutant allele retains some ability to rescue daughters from the otherwise lethal maternal effect of da; however, lowering maternal da+ activity appears to decrease Sxlf7,M1 functioning, consistent with other evidence that the parental allele, SxlM1, is not fully constitutive. In the absence of a wild-type Sxl allele, Sxlf7,M1 daughters that survive the da maternal effect are phenotypically male and sterile; in con- trast, the addition to this genotype of a wild-type Sxl allele in trans renders survivors phenotypically female, but still sterile with masculinized gonads. The latter genotype of female is fertile provided mothers carry at least one da+ allele. The ability of Sxlf7,M1 to rescue daughters is greatly enhanced by mutations in the autosomal, male- specific-lethal loci, genes involved in hyperactivation of X- linked genes in males. The basis for this enhancement is related to the ability of these same mutations to enhance the survival of Sxlf7,M1 hemizygous females. Although Sxlf7,M1 was used to demonstrate the ability of Sxl gene products to activate Sxl+ alleles in trans, it can be inferred that this allele is far below wild type in this activity. Sxlf7,M1 is a dominant suppressor of sis-a female-specific lethality, gen- erating sterile females remarkably similar to those described above rescued from the da maternal effect. Unlike SxlM1,f3, fails to complement Sxlf2593; yet partially complements SxlM1,f3 and SxlfPb, generating sterile phenotypic males. Allele supports oogenesis in homozygous mutant germ-line clones induced by mitotic recombination. In males, mutant allele suppresses the otherwise lethal effect of a duplication of region 3C2-5A2; addition of Sxl+ to this aneuploid genotype generates mosaic intersexes indicating that the positive autoregulatory activity of Sxl products can bypass the X/A signal. Double heterozygote with fs(1)A1621 is sterile (like Sxlf1 and unlike SxlM1,f3). # Sxlf9 phenotype: A lethal hypomorphic allele defective in some very early steps in the sex-determination process, but which has no adverse effect on the growth or sexual development of homozy- gous mutant diplo-X clones induced by mitotic recombination. Rare escapers at 18 are phenotypically female; nevertheless, it has a dominant masculinizing effect on the phenotype of triploid intersexes (2X:3A) and interacts in a dominant-lethal fashion with mutations in da or sis-a, both early acting posi- tive regulators of Sxl. Fully complements SxlfPR class (par- tial deletions of Sxl information that impair later functions of the gene more than earlier). Complements SxlM1,fPa-ra. # Sxlf2593 phenotype: A hypomorphic allele that is temperature sensitive for most Sxl functions. Perhaps most notable for the fact that homozygote viability can be quite high, with the females developing as true intersexes (their specific grade of inter- sexuality depends on temperature). Lethal over a deficiency, a null allele, or Sxlf7,M1 at any temperature; at permissive temperatures, weakly complements SxlM1,f3 and hypomorphic alleles of the SxlfPR class, generating (true) intersexual escapers; complementation better with SxlfPb, generating sterile females; fully complements Sxlf2, Sxlf9, and Sxlfhv1. # Sxlfhv1 phenotype: A subliminal allele, viable and fertile as homozy- gous females, but with greatly reduced viability in trans to nulls. Polytene chromosomes of Sxlfhv1/Sxlf1 larvae that sur- vive to third instar hyperincorporate uridine, revealing female dosage compensation upsets. Mutation of mle appears to partially masculinize this heteroallelic combination and may slightly increase viability under some conditions. Sxlfhv1 homozygotes and heterozygotes display an increased requirement for maternal da+ activity, suggestive of defects in early Sxl regulation. # SxlfLS phenotype: A lethal hypomorphic allele that is able to initiate female development, but is defective in its ability to main- tain the female developmental commitment and/or to elicit female sexual differentiation. It is masculinizing in homozy- gous mutant somatic clones induced by mitotic recombination, and it causes the tissue in such clones to grow poorly; nevertheless, it has no dominant effect on the sexual pheno- type of triploid intersexes, nor does it interact in a dom- inant fashion with mutations in da or sis-a, both early acting positive regulators of Sxl. Fully complements Sxlf9, which appears to have a very different set of defects. # SxlfP7BO phenotype: Female-lethal null allele that appears to be deleted for the entire Sxl transcription unit. Males are fully viable, fertile, and display normal male sexual behavior. # SxlfPa phenotype: A hybrid-dysgenesis-induced apparent null allele selected as an intragenic suppressor of SxlM1 male lethality. Only characterized in cis combination with SxlM1. A P-element insertion 5' to the site of the DNA insertion in SxlM1 but still within the region of Sxl transcribed at all stages. Revertible. # SxlfPa-ra phenotype: A hybrid-dysgenesis-induced derivative of SxlM1,fPa selected for having regained the ability to complement Sxlf9. This complex allele disrupts both male and female development, with the magnitude of the effects in either sex depending on culture temperature in a reciprocal fashion: high temperature is more permissive for females and less permissive (more fem- inizing) for males. Intersexual males show little male sexual behavior and stimulate courtship from other males. Dominant male-lethal effects are greatly enhanced by the presence of a duplication of Sxl+ in trans; male escapers with both alleles exhibit an unusual dorsalization of the abdomen, their ster- nites being variably transformed into tergites. # SxlfPb phenotype: A P-insertion-induced lethal hypomorphic allele with the unusual distinction of displaying a mosaic intersex pheno- type in homozygous mutant diplo-X clones induced by mitotic recombination; hence, appears to be defective in the cellular maintenance of the female sexual commitment. Under dysgenic conditions, can mutate further to less extreme or to more extreme condition. Partially complements Sxlf7,M1, generating masculinized individuals; partially complements Sxlf2593, gen- erating sterile females; fully complements Sxlf9. # SxlM1 phenotype: Unconditionally lethal to males, even in the pres- ence of a Sxl+ duplication. Retains normal level of female function as evidenced by full viability and fertility of homozygous and hemizygous mutant females. Recovered by virtue of ability to bypass the normal requirement by females for maternally supplied da+ product, a positive regulator of Sxl+; however, bypass is incomplete at higher temperatures. Pheno- type in both sexes results from expression of Sxl+ female sex determination and dosage compensation functions largely (though not completely) independently of the normal controls. This is shown by the observation that induction of mutations in cis that suppress dominant, male-specific lethality is invariably associated with a corresponding reduction in Sxl+ female-specific activities and the dominant da maternal-effect bypass phenotype. SxlM1 is lethal to most gynandromorphs by the pharate-adult stage, disrupting the development of their haplo-X tissue in a cell-autonomous fashion; mutant haplo-X tissue in gynandromorphs is often, but not always, feminized. This variable penetrance of the sex transformation suggests a residual level of control by the X/A balance. SxlM1 feminizes triploid intersexes, killing them as pharate adults, while suppressing B and Hw alleles in a fashion consistent with expectations for constitutive expression of normal female dosage-compensation functions. Analysis of effects on the dosage compensation of the very early acting segmentation gene, run, suggests that constitutive expression of female functions is not observed prior to the time when the later Sxl promoter is required and RNA processing control is known to be operating. Since run dosage compensation during this period does require functioning of maternal da+, zygotic Sxl+, and the X/A balance, the ability of SxlM1 to bypass these controls during later stages of development would seem to indicate that the effect of the mutant lesion it carries is on Sxl-RNA splicing, a process that these other Sxl+ regulators may only affect indirectly. The position of the SxlM1 mutant lesion in the vicinity of the male-specific exon is suggestive in this connection. Variable expressivity of this mutant allele may underlie two additional observations: (1) SxlM1 male lethality can be suppressed by fs(1)A1621, yet fs(1)A1621 female steril- ity can be suppressed by SxlM1, and (2) transplants of SxlM1/Y and SxlM1/+ germ cells show that although the allele does not appear to interfere with spermatogenesis in testes, it blocks the otherwise masculinizing effect of testicular somatic tis- sue on diplo-X (female) germ cells. # sy: see oss #*Sy: Stubby location: 1- or 2- (rearrangement). discoverer: Ives, 34j31. phenotype: Bristles short and thick, especially humerals and notopleurals. Male sterile. RK2. cytology: Associated with T(1;2)Sy; breakpoints unknown, but break in X is genetically at the right end. # Sy30: see Bl30 # Sy31l19: see Bl31l # Syb: Synaptobrevin location: 2- {60}. origin: Isolated from a Drosophila cDNA library using a bovine cDNA probe. references: Sudhoff, Baumert, Perin, and Jahn, 1989, Neuron 2: 1475-81. phenotype: Encodes a 20 kd polypeptide that is recognized by antibodies to rat synaptobrevin. Synaptobrevin is an intrin- sic membrane protein of small synaptic vesicles from mammalian brain; it is highly homologous to Torpedo VAMP-1. Signal from Drosophila heads exceeds that from rat brain suggesting that it is an abundant protein in flies. cytology: Placed in 46E-F by in situ hybridization to polytene chromosomes. molecular biology: The isolated cDNA clone contained an 0.8 kb insert whose conceptual amino acid sequence defines a polypeptide of 152 amino acids with a calculated molecular weight of 16,585. The polypeptide contains a 47- amino-acid N-terminal sequence that is rich in asparagine (26%) and shows little homology to the N-terminal sequences of mammals and Torpedo; the next 63 amino acids are highly con- served and display 75% identity in all three species; this region is followed by a putative transmembrane domain of 20 amino acids which display 60% identity with bovine synaptobre- vin; finally the C-terminal domain, which is thought to be intravesicular comprises 22 amino acids in Drosophila, but only two in bovine and Torpedo polypeptides. Northern blots of Drosophila head RNA reveals mRNAs of 0.85 and 0.9 kb, much shorter than the 2.2 kb observed in mammals. #*syn: syndrome location: 3-14.7. origin: / ray induced. discoverer: Wallbrunn, 61i21. references: 1964, DIS 39: 58. phenotype: Eyes of male translucent brown, of female slightly darker than normal. Wings of male held at right angle to body, of female held out at about 45. Viability low. Both sexes sterile. RK2. # Synaptobrevin: see Syb # syndrome: see syn