A splicing enhancer complex controls alternative splicing of doublesex pre-mRNA

Area of Science:

• Molecular Biology
• Genetics
• Developmental Biology

Background:

• Alternative splicing is crucial for generating protein diversity.
• The Drosophila doublesex (dsx) gene's alternative splicing dictates sexual fate.
• The transformer (tra) and transformer 2 (tra2) genes are known regulators of dsx splicing.

Purpose of the Study:

• To elucidate the mechanism by which transformer (tra) and transformer 2 (tra2) regulate female-specific dsx splicing.
• To identify the splicing factors involved in the formation of the dsx splicing regulatory complex.

Main Methods:

• Affinity purification of protein complexes bound to dsx pre-mRNA.
• Biochemical analysis of protein components within the purified complex.
• In vitro splicing assays to assess the sufficiency of splicing factors.

Main Results:

• Tra and Tra2 recruit general splicing factors, including serine/arginine-rich (SR) proteins, to a downstream regulatory element.
• Tra, Tra2, and SR proteins are sufficient to commit dsx pre-mRNA to female-specific splicing.
• Differential abilities of SR proteins in forming the commitment complex were observed.

Conclusions:

• Tra, Tra2, and SR proteins form an essential splicing enhancer complex for female-specific dsx pre-mRNA splicing.
• This complex plays a critical role in sexual development by regulating alternative splicing.
• The findings provide insights into the intricate regulation of gene expression through splicing.