Expression of Na/Pi cotransport from opossum kidney cells in Xenopus laevis oocytes

Biochim Biophys Acta. 1993 Aug 18;1178(2):141-5. doi: 10.1016/0167-4889(93)90004-9.

Abstract

Xenopus laevis oocytes have been used for the expression of Na/Pi-cotransport activity by injections of poly(A)+ RNA (mRNA) isolated from an established renal cell line (OK cells). 3-5 days after mRNA injection, Na-dependent phosphate (Pi) uptake by oocytes was increased in a dose-dependent manner; there was no increase in Na-independent Pi uptake. Sucrose density-gradient fractionation indicated that the mRNA species encoding this activity is 2.4-2.8 kb in length. In Northern blots, using a cDNA probe related to human kidney-cortex Na/Pi-cotransport activity (NaPi-3), hybridization with a mRNA-species of 2.4-2.6 kb was obtained. Kinetic characterization ([Pi], [Na]) showed that expressed transport activity has properties similar to apical Na/Pi cotransport in OK cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Transport
  • Carrier Proteins / biosynthesis*
  • Carrier Proteins / genetics
  • Cell Line
  • Kidney / metabolism*
  • Kidney Tubules, Proximal / metabolism
  • Kinetics
  • Nucleic Acid Hybridization
  • Oocytes
  • Opossums
  • Phosphates / metabolism*
  • Poly A / genetics
  • RNA, Messenger / genetics
  • Recombinant Proteins / biosynthesis
  • Sodium / metabolism*
  • Sodium-Phosphate Cotransporter Proteins
  • Symporters*
  • Xenopus laevis

Substances

  • Carrier Proteins
  • Phosphates
  • RNA, Messenger
  • Recombinant Proteins
  • Sodium-Phosphate Cotransporter Proteins
  • Symporters
  • Poly A
  • Sodium