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Abstract Co-adaptation of cytoplasmic and nuclear genomes are critical to physiological function for many species. Despite this understanding, hybridization can disrupt co-adaptation leading to a mismatch between maternally-inherited cytoplasmic genomes and biparentally inherited nuclear genomes. Few studies have examined the consequences of cytonuclear interactions to physiological function across environments. Here, we quantify the degree of co-introgression between chloroplast and nuclear-chloroplast (N-cp) genes across repeated hybrid zones and its consequences to physiological function across environments. We use whole-genome resequencing and common garden experiments with clonally replicated genotypes sampled across the natural hybrid zone betweenPopulus trichocarpaandP. balsamifera. We use geographic clines to test for co-introgression of the chloroplast genome with N-cp and non-interacting nuclear genes. Co-introgression of chloroplast and N-cp genes was limited although contact zone-specific patterns suggest that local environments may influence co-introgression. Combining ancestry estimates with phenotypic data across common gardens revealed that mismatches between chloroplast and nuclear ancestry can influence physiological performance, but the strength and direction of these effects vary depending on the environment. Overall, this study highlights the importance of cytonuclear interactions to adaptation, and the role of environment in modifying the effect of those interactions.
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Inheritance through the cytoplasm
Abstract Most heritable information in eukaryotic cells is encoded in the nuclear genome, with inheritance patterns following classic Mendelian segregation. Genomes residing in the cytoplasm, however, prove to be a peculiar exception to this rule. Cytoplasmic genetic elements are generally maternally inherited, although there are several exceptions where these are paternally, biparentally or doubly-uniparentally inherited. In this review, we examine the diversity and peculiarities of cytoplasmically inherited genomes, and the broad evolutionary consequences that non-Mendelian inheritance brings. We first explore the origins of vertical transmission and uniparental inheritance, before detailing the vast diversity of cytoplasmic inheritance systems across Eukaryota. We then describe the evolution of genomic organisation across lineages, how this process has been shaped by interactions with the nuclear genome and population genetics dynamics. Finally, we discuss how both nuclear and cytoplasmic genomes have evolved to co-inhabit the same host cell via one of the longest symbiotic processes, and all the opportunities for intergenomic conflict that arise due to divergence in inheritance patterns. In sum, we cannot understand the evolution of eukaryotes without understanding hereditary symbiosis.
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- PAR ID:
- 10369024
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Heredity
- Volume:
- 129
- Issue:
- 1
- ISSN:
- 0018-067X
- Page Range / eLocation ID:
- p. 31-43
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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