Sex-lethal explained

Sex-lethal (Sxl) is a gene found in Dipteran insects, named for its mutation phenotype in Drosophila melanogaster .^{[1] [2]} It is most closely related to the ELAV/HUD subfamily of splicing factors.^[3]

In fruit flies, this protein participates in alternative splicing of the transformer gene, deciding the sex of the fly.^[4] It induces female-specific alternative splicing of the transformer (tra) pre-mRNA by binding to the tra uridine-rich polypyrimidine tract at the non-sex-specific 3' splice site during the sex-determination process. SXL binds also to its own pre-mRNA and promotes female-specific alternative splicing.^{[5] [6]} SXL contains an N-terminal Gly/Asn-rich domain that may be responsible for the protein-protein interaction, and tandem RNA recognition motifs (RRMs) that show high preference to bind single-stranded, uridine-rich target RNA transcripts.^[7]

Notes and References

1. Maine EM, Salz HK, Cline TW, Schedl P . The Sex-lethal gene of Drosophila: DNA alterations associated with sex-specific lethal mutations . English . Cell . 43 . 2 Pt 1 . 521–9 . December 1985 . 3000609 . 10.1016/0092-8674(85)90181-3 . 32594881 . free .
2. Meise M, Hilfiker-Kleiner D, Dübendorfer A, Brunner C, Nöthiger R, Bopp D . Sex-lethal, the master sex-determining gene in Drosophila, is not sex-specifically regulated in Musca domestica . Development . 125 . 8 . 1487–94 . April 1998 . 10.1242/dev.125.8.1487 . 9502729 .
3. Schütt C, Nöthiger R . Structure, function and evolution of sex-determining systems in Dipteran insects . Development . 127 . 4 . 667–77 . February 2000 . 10.1242/dev.127.4.667 . 10648226 .
4. Bell LR, Maine EM, Schedl P, Cline TW . Sex-lethal, a Drosophila sex determination switch gene, exhibits sex-specific RNA splicing and sequence similarity to RNA binding proteins . Cell . 55 . 6 . 1037–46 . December 1988 . 3144435 . 10.1016/0092-8674(88)90248-6 . 22691059 .
5. Crowder SM, Kanaar R, Rio DC, Alber T . Absence of interdomain contacts in the crystal structure of the RNA recognition motifs of Sex-lethal . Proceedings of the National Academy of Sciences of the United States of America . 96 . 9 . 4892–7 . April 1999 . 10220389 . 10.1073/pnas.96.9.4892 . 21787 . 1999PNAS...96.4892C . free .
6. Penalva LO, Sánchez L . RNA binding protein sex-lethal (Sxl) and control of Drosophila sex determination and dosage compensation . Microbiology and Molecular Biology Reviews . 67 . 3 . 343–59, table of contents . September 2003 . 12966139 . 10.1128/mmbr.67.3.343-359.2003 . 193869 .
7. Samuels M, Deshpande G, Schedl P . Activities of the Sex-lethal protein in RNA binding and protein:protein interactions . Nucleic Acids Research . 26 . 11 . 2625–37 . June 1998 . 9592147 . 10.1093/nar/26.11.2625 . 147605 .