RRC ID 47749
Author Saito S, Ohkita M, Saito CT, Takahashi K, Tominaga M, Ohta T.
Title Evolution of Heat Sensors Drove Shifts in Thermosensation between Xenopus Species Adapted to Different Thermal Niches.
Journal J Biol Chem
Abstract Temperature is one of the most critical environmental factors affecting survival, and thus species that inhabit different thermal niches have evolved thermal sensitivities suitable for their respective habitats. During the process of shifting thermal niches, various types of genes expressed in diverse tissues, including those of the peripheral to central nervous systems, are potentially involved in the evolutionary changes in thermosensation. To elucidate the molecular mechanisms behind the evolution of thermosensation, thermal responses were compared between two species of clawed frogs (Xenopus laevis and Xenopus tropicalis) adapted to different thermal environments. X. laevis was much more sensitive to heat stimulation than X. tropicalis at the behavioral and neural levels. The activity and sensitivity of the heat-sensing TRPA1 channel were higher in X. laevis compared with those of X. tropicalis The thermal responses of another heat-sensing channel, TRPV1, also differed between the two Xenopus species. The species differences in Xenopus TRPV1 heat responses were largely determined by three amino acid substitutions located in the first three ankyrin repeat domains, known to be involved in the regulation of rat TRPV1 activity. In addition, Xenopus TRPV1 exhibited drastic species differences in sensitivity to capsaicin, contained in chili peppers, between the two Xenopus species. Another single amino acid substitution within Xenopus TRPV1 is responsible for this species difference, which likely alters the neural and behavioral responses to capsaicin. These combined subtle amino acid substitutions in peripheral thermal sensors potentially serve as a driving force for the evolution of thermal and chemical sensation.
Volume 291(21)
Pages 11446-59
Published 2016-5-20
DOI 10.1074/jbc.M115.702498
PII S0021-9258(20)40881-6
PMID 27022021
PMC PMC4900287
MeSH Acclimatization / genetics Acclimatization / physiology* Amino Acid Substitution Animals Ankyrin Repeat Biological Evolution Calcium Signaling Evolution, Molecular Female HeLa Cells Humans Oocytes / metabolism Phylogeny Rats Species Specificity TRPV Cation Channels / chemistry TRPV Cation Channels / genetics TRPV Cation Channels / physiology Thermosensing / genetics Thermosensing / physiology* Transient Receptor Potential Channels / chemistry Transient Receptor Potential Channels / genetics Transient Receptor Potential Channels / physiology Xenopus / genetics Xenopus / physiology* Xenopus Proteins / chemistry Xenopus Proteins / genetics Xenopus Proteins / physiology Xenopus laevis / genetics Xenopus laevis / physiology
IF 4.238
Times Cited 10
Clawed frogs / Newts X. tropicalis