title: The JAK/STAT signaling pathway is required for the initial choice of sexual identity in Drosophila melanogaster.
abstract: The choice of sexual identity in Drosophila is determined by a system that measures the X chromosome to autosome ratio (X/A). This system depends upon unequal expression of X-linked numerator genes in 1X and 2X nuclei. The numerators activate a special Sxl promoter, Sxl-Pe, in 2X/2A nuclei, but not 1X/2A nuclei. By multimerizing a conserved Sxl-Pe sequence block, we generated a gain-of-function promoter, Sxl-PeGOF, that is inappropriately active in 1X/2A nuclei. GOF activity requires the X-linked unpaired (upd) gene, which encodes a ligand for the Drosophila JAK/STAT signaling pathway. upd also functions as a numerator element in regulating wild-type Sxl-Pe reporters. We demonstrate that the JAK kinase, Hopscotch, and the STAT DNA-binding protein, Marelle, are also required for Sxl-Pe activation.
authors.affiliation: Department of Molecular Biology, Princeton University, New Jersey 08544, USA.
authors.forename: T M
authors.initials: TM
authors.lastname: Jinks
authors.forename: A D
authors.initials: AD
authors.lastname: Polydorides
authors.forename: G
authors.initials: G
authors.lastname: Calhoun
authors.forename: P
authors.initials: P
authors.lastname: Schedl
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000378:metabolism*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics; D005260:Female; D006023:Glycoproteins / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases; D053612:Janus Kinases; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011494:Protein Kinases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D020449:Repetitive Sequences, Amino Acid; D019849:Sex Determination Processes; D015398:Signal Transduction; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors
chemical_list: D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D006023:Glycoproteins; D016601:RNA-Binding Proteins; C067777:Sxl protein, Drosophila; D015534:Trans-Activators; D014157:Transcription Factors; C115570:upd1 protein, Drosophila; D011494:Protein Kinases; D011505:Protein-Tyrosine Kinases; D053612:Janus Kinases; C085845:hop protein, Drosophila; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases