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Title: Mutation pressure, drift, and the pace of molecular coevolution
Most aspects of the molecular biology of cells involve tightly coordinated intermolecular interactions requiring specific recognition at the nucleotide and/or amino acid levels. This has led to long-standing interest in the degree to which constraints on interacting molecules result in conserved vs. accelerated rates of sequence evolution, with arguments commonly being made that molecular coevolution can proceed at rates exceeding the neutral expectation. Here, a fairly general model is introduced to evaluate the degree to which the rate of evolution at functionally interacting sites is influenced by effective population sizes ( N e ), mutation rates, strength of selection, and the magnitude of recombination between sites. This theory is of particular relevance to matters associated with interactions between organelle- and nuclear-encoded proteins, as the two genomic environments often exhibit dramatic differences in the power of mutation and drift. Although genes within low N e environments can drive the rate of evolution of partner genes experiencing higher N e , rates exceeding the neutral expectation require that the former also have an elevated mutation rate. Testable predictions, some counterintuitive, are presented on how patterns of coevolutionary rates should depend on the relative intensities of drift, selection, and mutation.  more » « less
Award ID(s):
1927159 1922914
PAR ID:
10448978
Author(s) / Creator(s):
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
120
Issue:
27
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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