Arabidopsis PRMT5 buffers pre-mRNA splicing and development against genetic variation in donor splice sites

Area of Science:

• Molecular Biology
• Developmental Biology
• Evolutionary Biology

Background:

• Genetic variation in splice sites drives alternative splicing, impacting organismal traits.
• Canalization maintains consistent phenotypes despite genetic or environmental changes.
• Protein arginine methyltransferase 5 (PRMT5) is a crucial splicing regulator.

Purpose of the Study:

• To investigate the role of PRMT5 in buffering splicing against genetic variation.
• To understand PRMT5's contribution to canalization and adaptive evolution.

Main Methods:

• Studied two genetically divergent Arabidopsis thaliana accessions.
• Analyzed PRMT5's effects on splicing and development.
• Examined single nucleotide polymorphisms (SNPs) affecting donor splice sites.

Main Results:

• PRMT5 inactivation significantly amplified splicing differences between accessions.
• Phenotypic variations between accessions were also exacerbated by PRMT5 inactivation.
• PRMT5 appears to buffer splicing against variations at weak donor splice sites.

Conclusions:

• PRMT5 plays a key role in developmental canalization by mitigating the effects of splice site polymorphisms.
• PRMT5 facilitates the evolution of adaptive splicing patterns by maintaining developmental stability.
• PRMT5's buffering capacity is essential for balancing genetic variation and phenotypic consistency.