Epistasis among adaptive mutations in deer mouse hemoglobin.
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ABSTRACT:
SUBMITTER: Natarajan C
PROVIDER: S-EPMC4409680 | biostudies-literature | 2013 Jun
REPOSITORIES: biostudies-literature
Publications
Epistasis among adaptive mutations in deer mouse hemoglobin.
Natarajan Chandrasekhar C Inoguchi Noriko N Weber Roy E RE Fago Angela A Moriyama Hideaki H Storz Jay F JF
Science (New York, N.Y.) 20130601 6138
Epistatic interactions between mutant sites in the same protein can exert a strong influence on pathways of molecular evolution. We performed protein engineering experiments that revealed pervasive epistasis among segregating amino acid variants that contribute to adaptive functional variation in deer mouse hemoglobin (Hb). Amino acid mutations increased or decreased Hb-O2 affinity depending on the allelic state of other sites. Structural analysis revealed that epistasis for Hb-O2 affinity and a ...[more]
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