Regulated expression and RNA processing of transcripts from the Srp20 splicing factor gene during the cell cycle

Area of Science:

• Molecular Biology
• Gene Regulation
• RNA Splicing

Background:

• SR proteins are essential eukaryotic splicing factors.
• SRp20 is the smallest member of the SR protein family.
• Alternative splicing influences gene expression and is regulated by splicing factors.

Purpose of the Study:

• To characterize the structure and transcriptional regulation of the SRp20 gene.
• To investigate the role of SRp20 in alternative splicing and cell cycle regulation.
• To identify regulatory elements in the SRp20 promoter.

Main Methods:

• Gene mapping and structural analysis of the Srp20 gene.
• Transfection experiments to study SRp20 transcript and protein production.
• Cell synchronization and starvation/stimulation assays to analyze SRp20 expression during the cell cycle.
• Promoter analysis using reporter constructs and E2F expression plasmids.

Main Results:

• The Srp20 gene consists of alternative and constitutive exons and is located on chromosome 17.
• SRp20 genomic DNA transfection produces both standard and alternatively spliced transcripts.
• SRp20 mRNA splicing is regulated during the cell cycle, with alternative exon inclusion higher in starved cells and decreasing upon serum stimulation.
• SRp20 transcripts are induced in late G1/early S phase.
• The SRp20 promoter contains E2F binding sites and is activated by E2F.

Conclusions:

• SRp20 gene expression and splicing are regulated during the cell cycle.
• SRp20 plays a role in cell cycle-dependent alternative splicing.
• E2F transcription factors may regulate SRp20 expression during the cell cycle.