The genes of Na, K-ATPase, a selfreview

Abstract

The review is devoted to analysis of research carried out in the author's laboratory on structure-function relationships in genes coding for Na, K-ATPases. Also considered are problems related to molecular evolution of ion-transporting ATPases.This brief review is devoted to a fragment of research carried out in my laboratory, the Laboratory of Human Genes Structure and Function at the Shemyakin

Functional Expression of the Colonic H+,K+-ATPase α-Subunit

“…The X ϩ ,K ϩ -ATPases, which also include the Na ϩ ,K ϩ -ATPase isozymes, share a common catalytic cycle, the ability to extrude a cation (Na ϩ or H ϩ , respectively) from the cell in exchange for K ϩ , and an apparent requirement for heterodimeric structure (2)(3)(4). To date, cDNAs encoding homologous H ϩ ,K ϩ -ATPase ␣-subunits have been cloned from gastric parietal cells (␣ G or HK␣1) (5,6), rat and guinea pig distal colon (␣ C or HK␣2) (7,8), toad urinary bladder (␣ bl or HK␣3) (9), and human skin (ATP1AL1 or HK␣4) (10).…”

In VitroEffect of Valepotriates Isolated fromValeriana glechomifoliaon Rat P-Type ATPases

“…This can be supported by the phylogenetic tree of P-type ATPases [2]. Moreover, the sequence homology between Na + /K + -ATPase and H + /K + -ATPase α subunit is slightly lower than among Na + /K + -ATPase α subunit isoforms [27], but considerably higher than between Na + /K + -ATPase and SERCA [28], also helping to explain the equivalence between the IC 50 for the rat kidney isoform (the ouabain-resistant α 1 isoform) and the rat brain hemisphere isoforms (mainly the ouabain-sensitive α 2 and α 3 isoforms). Although our findings clearly point out the selectivity of valepotriates for Na + /K + -ATPase, we cannot exclude that the inhibition might be due to the nonspecific interaction with the surrounding membrane, modifying its fluidity and organization, due to drug lipophilicity and net charge as suggested for some psychotropic substances [29,30].…”