Effect of loss of transcription factor CLAMP on sex-specific splicing in Drosophila third instar larvae (L3) stage

ABSTRACT: CLAMP transcription factor is a GA binding protein that recruits the male dosage compensation complex MSL to male X-chromosome, thus upregulating transcription level twice that of female X-chromosomes. Interestingly, CLAMP is essential for survival of both male and female individuals. However, what function it plays at the autosomes, especially in females is not known. It is well establised that GA-rich sequences to which CLAMP bind have evolved from polypyrimidine tracts that regulate splicing. Also, MALDI-MS data shows that CLAMP binds to RNA binding proteins involved in sex-specific splicing like, Squid. Furthermore, as part of MSL complex CLAMP interacts with MLE, a RNA helicase which is a known component of spliceosome complex conserved from flies to humans. Thus, we hypothesized that CLAMP plays a role in sex-spcific splicing. Given that CLAMP is a transcription factor, understanding mechanism of how it regulates splicing will add to our understanding about how regulators of gene expression shape the transcriptome differentially between males and females. We tested our hypothesis by identifying CLAMP dependent female and male sex-specific splicing events by analysing RNA-seq data from control as well as clampnull mutant male and female third instar larvae (L3) using suppa based time2splice pipeline (https://github.com/ashleymaeconard/time2splice). We identified 189 and 211 CLAMP dependent splicing events in female and male L3. Out of these 139 were female sex-specific splicing whereas 161 was male-sex-specific splicing. 50 splicing events identified as CLAMP dependent were non-specific to any particular sex, and were affect in both the sexes. Interestingly, we identified splicing of master regulator of sex-determination sxl affected by absence of CLAMP in females whereas splicing of one of the sex-determination pathway effectors, tra regulated by CLAMP in males. These findings indicate CLAMP plays important role in determining sex-specific transcript diversity in Drosophila.

ORGANISM(S): Drosophila melanogaster

PROVIDER: GSE220455 | GEO | 2023/08/02

REPOSITORIES: GEO