Expression cloning and cDNA sequencing of the Na+/glucose co-transporter

Nature. 1987 Nov 26-Dec 2;330(6146):379-81. doi: 10.1038/330379a0.

Abstract

Organic substrates (sugars, amino acids, carboxylic acids and neutrotransmitters) are actively transported into eukaryotic cells by Na+ co-transport. Some of the transport proteins have been identified--for example, intestinal brush border Na+/glucose and Na+/proline transporters and the brain Na+/CI-/GABA transporter--and progress has been made in locating their active sites and probing their conformational states. The archetypical Na+-driven transporter is the intestinal brush border Na+/glucose co-transporter (see ref. 8), and a defect in the co-transporter is the origin of the congenital glucose-galactose malabsorption syndrome. Here we describe cloning of this co-transporter by a method new to membrane proteins. We have sequenced the cloned DNA and have found no homology between the Na+/glucose co-transporter and either the mammalian facilitated glucose carrier or the bacterial sugar transport proteins. This suggests that the mammalian Na+-driven transporter has no evolutionary relationship to the other sugar transporters.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular*
  • DNA / metabolism*
  • Female
  • Heart Ventricles / metabolism
  • Intestinal Mucosa / metabolism
  • Jejunum / metabolism
  • Molecular Sequence Data
  • Monosaccharide Transport Proteins / genetics*
  • Oocytes / metabolism
  • Poly A / genetics
  • RNA / genetics
  • RNA, Messenger / genetics
  • Rabbits
  • Transcription, Genetic
  • Xenopus laevis

Substances

  • Monosaccharide Transport Proteins
  • RNA, Messenger
  • Poly A
  • RNA
  • DNA

Associated data

  • GENBANK/X06419