Sxl protein mediates differential expression of genes further downstream in the developmental pathway
In females, active Sxl protein produced from Pm leads toproduction of proteins that facilitate female development—first Tra protein, which then, with Tra-2, facilitates splicing of the mRNA for active Dsx protein. In males:
A. the absence of Sxl leads to a different splicing pattern of tra transcripts; a different version of Dsx isproduced that leads to male development.
B. transcription from promoter Pe results in acharacteristic splicing pattern and the production of a burst of active Sxl protein.
C. only stop codons are recognized, leading to splicing of Tra and overactivity of SxI.
D. the start codons are preferentially removed in splicing, causing a premature termination of Dsx translation leading to male development.
A
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