Alternative splicing is frequent during early embryonic development in mouse

Area of Science:

• Molecular Biology
• Developmental Biology
• Genomics

Background:

• Alternative splicing increases transcriptome complexity, with nearly all mammalian genes expressing multiple pre-mRNA isoforms.
• Knowledge of alternative splicing in early embryonic development is limited, often based on isolated examples.
• High-throughput technologies enable genome-wide studies of alternative splicing in mouse development.

Purpose of the Study:

• To conduct a genome-wide analysis of alternative splicing and isoform expression in mouse embryos and placenta during early development.
• To investigate the frequency and functional relevance of alternative splicing across developmental stages and tissues.
• To identify potential regulators of alternative splicing, such as RNA-binding proteins.

Main Methods:

• Genome-wide analysis using splicing-sensitive exon microarrays.
• Comparison of alternative isoform expression in embryonic day 8.5, 9.5, and 11.5 mouse embryos and placenta.
• Analysis of differential expression and splicing of RNA-binding proteins.

Main Results:

• Alternative splicing is frequent across developmental stages and tissues in mouse embryos, comparable to whole-transcript expression variation.
• Alternatively spliced genes are disproportionately involved in crucial developmental processes.
• Differential expression and splicing of RNA-binding proteins suggest their regulatory role in isoform variation. Fox2 protein levels predict alternative exon inclusion.

Conclusions:

• Alternative splicing is proposed as a key regulatory mechanism in embryonic development.
• Gene expression monitoring at both whole transcript and isoform levels is recommended for developmental studies.