Work

Patterns, mechanisms, and consequences of homoeologous exchange in allopolyploid angiosperms: a genomic and epigenomic perspective

Year: 2023

Type: article

Abstract: Allopolyploids result from hybridization between different evolutionary lineages coupled with genome doubling. Homoeologous chromosomes (chromosomes with common shared ancestry) may undergo recombination immediately after allopolyploid formation and continue over successive generations. The outcome of this meiotic pairing behavior is dynamic and complex. Homoeologous exchanges (HEs) may lead to the formation of unbalanced gametes, reduced fertility, and selective disadvantage. By contrast, HEs could act as sources of novel evolutionary substrates, shifting the relative dosage of parental gene copies, generating novel phenotypic diversity, and helping the establishment of neo-allopolyploids. However, HE patterns vary among lineages, across generations, and even within individual genomes and chromosomes. The causes and consequences of this variation are not fully understood, though interest in this evolutionary phenomenon has increased in the last decade. Recent technological advances show promise in uncovering the mechanistic basis of HEs. Here, we describe recent observations of the common patterns among allopolyploid angiosperm lineages, underlying genomic and epigenomic features, and consequences of HEs. We identify critical research gaps and discuss future directions with far-reaching implications in understanding allopolyploid evolution and applying them to the development of important phenotypic traits of polyploid crops.

Source: New Phytologist

DOI: 10.1111/nph.18927

Authors: Sontosh K. Deb, Patrick P. Edger, J. Chris Pires, Michael R. McKain

Institutions: Shahjalal University of Science and Technology, University of Alabama, Michigan State University, Colorado State University

Language: English

Topic: Chromosomal and Genetic Variations

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

Open Access status: bronze

Funders: National Science Foundation, University of Alabama, Directorate for Biological Sciences

Awards: RII Track-2 FEC: Consortium for Plant Invasion Genomics (CPING): Combining Big Data and Plant Collections to Understand Invasiveness, RoL: RUI: Collaborative Research: Understanding the Ecological and Genomic Bases of Local Adaptation in an Obligate Pollination Mutualism, G6176092842, RESEARCH-PGR: Genomics and Epigenomics of Subgenome Dominance in Hybrids and Allopolyploids, G6290411627