Molecular cloning of a new human G protein. Evidence for two Gi alpha-like protein families.

Journal Article

The amino acid sequence of a novel G protein alpha subunit (Gx alpha) has been deduced from the nucleotide sequence of a human cDNA clone isolated from a differentiated HL-60 cDNA library. The cDNA encodes a polypeptide of 354 amino acids (Mr 40,519) which is closely related to Gi alpha proteins. The amino acid sequence homology between Gx alpha and human myeloid Gi alpha is 86% with 15 nonconservative substitutions. Gx alpha also shares 86% homology with both rat brain and mouse macrophage Gi alpha but is more homologous (94%) to bovine brain Gi alpha with only 5 nonconservative amino acid differences. G proteins previously termed Gi alpha may fall into at least two distinct groups, with one including human myeloid Gi alpha, rat brain Gi alpha and mouse macrophage Gi alpha; and other Gx alpha and bovine brain Gi alpha. One group probably contains true Gi and the other a new class of G protein whose function remains to be determined.

Full Text

Duke Authors

Cited Authors

  • Didsbury, JR; Snyderman, R

Published Date

  • July 13, 1987

Published In

Volume / Issue

  • 219 / 1

Start / End Page

  • 259 - 263

PubMed ID

  • 3109953

International Standard Serial Number (ISSN)

  • 0014-5793

Language

  • eng

Conference Location

  • England