The combinatorial control of alternative splicing in C. elegans

Area of Science:

• Molecular Biology
• Developmental Biology
• Genetics

Background:

• Precise gene expression via alternative splicing is essential for normal development.
• Splicing factors (SFs) recognize RNA motifs to regulate splice variant selection.
• Understanding SF target specificity and combinatorial control in C. elegans is limited.

Purpose of the Study:

• To investigate the regulatory roles of four C. elegans SFs (ASD-1, FOX-1, MEC-8, EXC-7) in splicing.
• To identify the direct targets of these SFs and analyze their binding patterns.
• To elucidate how multiple SFs cooperate to control alternative splicing.

Main Methods:

• RNA sequencing (RNA-seq) to profile gene expression changes.
• In vitro binding assays to determine SF-RNA interactions.
• Bioinformatic analysis to identify SF binding sites and target genes.

Main Results:

• High overlap observed in the splicing targets of the four studied SFs.
• SF binding sites co-occur on pre-mRNAs more often than expected, indicating combinatorial regulation.
• Combinatorial SF control operates in distinct modes: proximity binding or conserved order binding.
• SF-regulated genes are enriched in cytoskeleton and ion channel functions.

Conclusions:

• Multiple SFs exhibit significant target overlap and combinatorial control over alternative splicing in C. elegans.
• This complex regulatory network is functionally significant and critical for development.
• Specific gene sets, including those for cytoskeleton and ion channels, rely on combinatorial splicing regulation.