Molecular evolution of mammalian aquaporin-2: further evidence that elephant shrew and aardvark join the paenungulate clade

Mol Biol Evol. 1997 Apr;14(4):363-71. doi: 10.1093/oxfordjournals.molbev.a025772.

Abstract

A 328-bp sequence from exon 1 of the gene for aquaporin-2 (AQP2) was compared in 12 mammalian species, representing as many eutherian orders. This sequence encodes the N-terminal half of this kidney-specific water channel protein. Most amino acid replacements, as well as an insertion, have occurred in extracellular loops connecting the transmembrane helices, in agreement with a lower functional importance of these loops. Phylogenetic analyses were performed with parsimony, distance, and maximum-likelihood methods. The AQP2 data set, alone as well as in combination with previously published alpha A-crystallin protein sequences, strongly supports a clade consisting of elephant, hyrax, aardvark, and elephant shrew, reaching bootstrap values of 99%. This finding fully agrees with the only other presently available sequence data sets that include these taxa, those of von Willebrand factor and interphotoreceptor retinoid-binding protein, and suggests that this extended paenungulate clade is one of the most conspicuous superordinal groupings in eutherian phylogeny. Some support was obtained for an artiodactyl/perissodactyl clade, while the grouping of pholidotes with edentates was contradicted.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Aquaporin 2
  • Aquaporin 6
  • Aquaporins*
  • Base Sequence
  • Crystallins / genetics
  • Evolution, Molecular*
  • Humans
  • Ion Channels / genetics*
  • Mammals / classification*
  • Mammals / genetics
  • Molecular Sequence Data
  • Phylogeny
  • Sequence Homology, Amino Acid
  • Sequence Homology, Nucleic Acid
  • Shrews / classification*
  • Shrews / genetics

Substances

  • AQP2 protein, human
  • Aquaporin 2
  • Aquaporin 6
  • Aquaporins
  • Crystallins
  • Ion Channels

Associated data

  • GENBANK/Y10629
  • GENBANK/Y10630
  • GENBANK/Y10631
  • GENBANK/Y10632
  • GENBANK/Y10633
  • GENBANK/Y10634
  • GENBANK/Y10635
  • GENBANK/Y10636
  • GENBANK/Y10637
  • GENBANK/Y10638