Domestication reduces alternative splicing expression variations in sorghum.

Area of Science:

• Plant genetics
• Molecular biology
• Genomics

Background:

• Domestication significantly reduces genomic diversity via population bottlenecks.
• Loss of genetic polymorphism is well-documented in cultivated species.
• Alternative transcript expression diversity remains less explored in domesticated plants.

Purpose of the Study:

• To investigate the impact of domestication on alternative transcript expression diversity in sorghum.
• To compare transcript isoform expression balance between wild and cultivated sorghum accessions.
• To explore potential regulatory mechanisms affected by domestication.

Main Methods:

• Utilized RNA sequencing (RNA-seq) data from cultivated and wild sorghum accessions.
• Focused on genes expressing two isoforms in sorghum.
• Estimated the ratio of expression levels between isoforms for each gene in each accession.

Main Results:

• Observed significantly more variation in isoform expression balance among wild sorghum accessions compared to cultivated ones.
• Found that cultivated sorghum accessions exhibit a more homogenous balance between gene isoforms.
• Identified potential impacts of reduced nucleotide diversity on regulatory elements controlling isoform expression.

Conclusions:

• Domestication leads to a more homogenous transcript isoform expression balance in sorghum.
• Loss of diversity during domestication may affect regulatory elements controlling alternative splicing.
• This study pioneers the genomic-scale investigation of domestication's impact on transcript isoform balance.