Reverse evolution in RH1 for adaptation of cichlids to water depth in Lake Tanganyika
Autor: | Haruka Nagai, Hiroo Imai, Yohey Terai, Tohru Sugawara, Michio Hori, Hidenori Nishihara, Norihiro Okada |
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Jazyk: | angličtina |
Rok vydání: | 2011 |
Předmět: |
Molecular Sequence Data
Fresh Water Locus (genetics) Ecological data Biology Tanzania Adaptive mutation Cichlid Genetics Animals Amino Acid Sequence Molecular Biology Alleles Phylogeny Ecology Evolution Behavior and Systematics Base Sequence Opsins Ecology Cichlids biology.organism_classification Adaptation Physiological Biological Evolution Water depth Waves and shallow water Amino Acid Substitution Habitat Genetic Change Sequence Alignment |
Zdroj: | Molecular Biology and Evolution. 28(No. 6):1769-1776 |
Popis: | Reverse evolution is a widespread phenomenon in biology, but the genetic mechanism for the reversal of a genetic change for adaptation to the ancestral state is not known. Here, we report the first case of complete reverse evolution of two amino acids, serine and alanine, at a single position in RH1 opsin pigment for adaptation to water depth. We determined RH1 sequences of cichlid fishes from four tribes of Lake Tanganyika with different habitat depths. Most of the species were divided into two types: RH1 with 292A for species in shallow water or 292S for species in deep water. Both types were adapted to their ambient light environments as indicated by the absorption spectra of the RH1 pigments. Based on the RH1 locus tree and ecological data, we inferred the ancestral amino acids at position 292 and the distribution of the depth ranges (shallow or deep) of ancestral species of each tribe. According to these estimates, we identified two distinct parallel adaptive evolutions: The replacement A292S occurred at least four times for adaptation from shallow to deep water, and the opposite replacement S292A occurred three times for adaptation from deep to shallow water. The latter parallelism represents the complete reverse evolution from the derived to the ancestral state, following back adaptive mutation with reversal of the RH1 pigment function accompanied by reversal of the species habitat shift. |
Databáze: | OpenAIRE |
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