Human Tra2 proteins jointly control a CHEK1 splicing switch among alternative and constitutive target exons

Area of Science:

• Molecular Biology
• Genetics
• Cell Biology

Background:

• Alternative splicing generates diverse mRNA isoforms from a single gene.
• RNA binding proteins (RBPs) play a crucial role in regulating alternative splicing.
• Transformer2 alpha (Tra2α) and Tra2β are RBPs implicated in splicing, but their distinct roles are unclear.

Purpose of the Study:

• To investigate the individual and combined roles of Tra2α and Tra2β in alternative splicing regulation.
• To identify target exons and genes controlled by Tra2α and Tra2β.
• To determine the functional consequences of Tra2 protein depletion on cellular processes.

Main Methods:

• Depletion of Tra2α and Tra2β proteins in cells.
• Analysis of splicing patterns of endogenous target exons.
• Gene expression analysis of target genes, including CHEK1.
• Assessment of DNA damage markers and cell viability.

Main Results:

• Simultaneous depletion of Tra2α and Tra2β, but not individual depletion, caused significant splicing shifts in target exons.
• Both constitutive and alternative target exons are under dual Tra2α-Tra2β control.
• Dual Tra2 depletion reduced full-length CHK1 protein, increased DNA damage marker γH2AX, and decreased cell viability.

Conclusions:

• Tra2α and Tra2β proteins act redundantly to control constitutive and alternative splicing.
• Paralog compensation by Tra2 proteins is essential for maintaining cell viability.
• Dysregulation of Tra2-controlled splicing impacts DNA damage response and cell survival pathways.