Splicing factor Sub2p is required for nuclear mRNA export through its interaction with Yra1p

Area of Science:

• Molecular Biology
• Cell Biology
• Genetics

Background:

• Yeast nuclear protein Yra1p is essential for messenger RNA (mRNA) export.
• Yra1p interacts with the mRNA transport factor Mex67p/Mtr2p at the nuclear pore.

Purpose of the Study:

• Investigate the role of SUB2, a DEAD box helicase involved in splicing, in mRNA export.
• Elucidate the interaction between Yra1p and Sub2p in the context of mRNA export.

Main Methods:

• Genetic interaction analysis between YRA1 and SUB2.
• In vivo and in vitro binding assays to study protein-protein interactions.
• Analysis of protein binding domains and competition assays.

Main Results:

• Mutation or overexpression of SUB2 impairs mRNA export.
• Yra1p and Sub2p directly bind to each other both in vivo and in vitro.
• Sub2p and Mex67p/Mtr2p compete for binding to the same domains on Yra1p.

Conclusions:

• The spliceosomal component Sub2p plays a significant role in mRNA export.
• Sub2p likely recruits Yra1p to mRNA for export.
• Mex67p/Mtr2p binding to Yra1p may displace Sub2p, facilitating nuclear pore passage.