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. 1996 May;143(1):303–314. doi: 10.1093/genetics/143.1.303

A Negative Feedback Mechanism Revealed by Functional Analysis of the Alternative Isoforms of the Drosophila Splicing Regulator Transformer-2

W Mattox 1, M E McGuffin 1, B S Baker 1
PMCID: PMC1207263  PMID: 8722783

Abstract

The Drosophila sex determination gene transformer-2 (tra-2) is a splicing regulator that affects the sex-specific processing of several distinct pre-mRNAs. While the tra-2 gene itself is known to produce alternative mRNAs that together encode three different TRA-2 protein isoforms, the respective roles of these isoforms in affecting individual pre-mRNA targets has remained unclear. We have generated transgenic fly strains with mutations affecting specific TRA-2 isoforms to investigate their individual roles in regulating the alternative processing of doublesex, exuperantia and tra-2 pre-mRNA. Our results indicate that in somatic tissues two different isoforms function redundantly to direct female differentiation and female-specific doublesex pre-mRNA splicing. In the male germline, where tra-2 has an essential role in spermatogenesis, a single isoform was found to uniquely perform all necessary functions. This isoform appears to regulate its own synthesis during spermatogenesis through a negative feedback mechanism involving intron retention.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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