Conjugated bile acid uptake by Xenopus laevis oocytes induced by microinjection with ileal Poly A+ mRNA

Biochem Biophys Res Commun. 1992 Aug 14;186(3):1455-62. doi: 10.1016/s0006-291x(05)81570-0.

Abstract

Apical membranes of ileal enterocytes contain the major Na+/bile acid cotransporter activity in mammals. Microinjection of guinea pig ileal mucosal Poly A+ mRNA (25 ng) into Xenopus oocytes resulted in 22,23-3H-cholyltaurine uptake at day 3 after injection (453 fmol/oocyte-hr), while control viral mRNA (25 ng) gave an uptake rate of 133 fmol/oocyte-hr. The transport rate increased in direct relationship to the concentration of injected mRNA, cholyltaurine, or Na+ in the incubation media. Uptake of cholyltaurine using rabbit ileal mucosal Poly A+ mRNA was 3891 fmole/oocyte-hr compared to rabbit jejunal-mucosa Poly A+ mRNA (control) injections inducing 728 fmol/oocyte-hr. Such expression of the ileal Na+/bile acid cotransporter may facilitate cloning of this key mammalian gene.

Publication types

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

MeSH terms

  • Animals
  • Biological Transport
  • Female
  • Guinea Pigs
  • Ileum
  • In Vitro Techniques
  • Intestinal Mucosa / physiology*
  • Kinetics
  • Microinjections
  • Mosaic Viruses / genetics
  • Oocytes / metabolism*
  • Poly A / administration & dosage
  • Poly A / genetics*
  • Poly A / metabolism
  • RNA, Messenger / administration & dosage
  • RNA, Messenger / genetics*
  • RNA, Messenger / metabolism
  • RNA, Viral / administration & dosage
  • RNA, Viral / genetics
  • RNA, Viral / metabolism
  • Rabbits
  • Taurocholic Acid / metabolism*
  • Xenopus laevis

Substances

  • RNA, Messenger
  • RNA, Viral
  • Poly A
  • Taurocholic Acid