Protein nonadditivity and stability contribute to heterosis in Arabidopsis hybrids and allotetraploids

ABSTRACT: Hybrid vigor or heterosis has been widely applied in agriculture and extensively studied at the genetic and gene expression levels. However, the biochemical mechanism underlying heterosis remains elusive. One theory suggests that a decrease in protein aggregation may occur in hybrids due to the presence of protein variants between parental alleles, but it has not been experimentally tested. Here, we report comparative analysis of soluble and insoluble proteomes in Arabidopsis intraspecific and interspecific hybrids or allotetraploids formed between A. thaliana and A. arenosa. Both intraspecific hybrids and interspecific allotetraploids displayed non-additivity of the expressed proteins, including many biotic and abiotic stress-responsive proteins. In the allotetraploids, homoeolog-expression bias was not observed among all proteins examined but could occur among 17-20% of the nonadditively expressed proteins with more A. thaliana-biased than A. arenosa-biased homoeologs, consistent with the transcriptome results. Analysis of the insoluble and soluble proteomes revealed more soluble proteins in the hybrids than their parents but not in allotetraploids. Most proteins in ribosomal biosynthesis and in the thylakoid lumen, membrane, and stroma, were in the soluble fractions, indicating a role of protein stability in photosynthetic activities for promoting growth. Together, these results support roles for nonadditive expression of stress-responsive proteins and reduction of protein biosynthesis in mediating heterosis in Arabidopsis hybrids and allotetraploids.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Arabidopsis Thaliana (ncbitaxon:3702) Arabidopsis Arenosa (ncbitaxon:38785) Arabidopsis Suecica (ncbitaxon:45249)

SUBMITTER: Z. Jeffrey Chen  

PROVIDER: MSV000089682 | MassIVE | Fri Jun 17 10:01:00 BST 2022

SECONDARY ACCESSION(S): PXD034635

REPOSITORIES: MassIVE