Identification of a processed protein related to the human chaperonins (hsp 60) protein in mammalian kidney.
The chaperonin family of proteins, which includes GroEL protein of E. coli, yeast heat shock protein (hsp-60) and the ribulose-1-5-bisphosphate carboxylase (Rubis Co.) subunit binding protein of plant chloroplasts, shows strong sequence homology to the Chinese hamster ovary (CHO) mitochondrial P1 protein. We have identified a 60 kDa protein from bovine kidney which by N-terminal sequencing gives the amino acid sequence AKDVKFGADARALLMLQGVDLLADA. Bovine whole kidney membranes were delipidated, solubilized with octyl glucoside and fractionated over an affinity column using the amiloride analog 5-N pyrazine amiloride as the ligand. After extensive washing with 200 mM NaCl, the column was eluted with pH 4.0 buffer. Analysis of column fractions on a 7.5% polyacrylamide gel revealed 3-4 bands with a predominant band at 60,000 Da. Amino acid analysis after transfer to immobilon membranes demonstrated sequence identity to the human HSP (60), extending 24 amino acids from the N-terminus, but lacking the leader sequence. These data indicate that a processed form of a protein related to the human HSP (60) chaperonin is associated with a membrane fraction in the mammalian kidney, and that the processed form of the protein binds strongly to an amiloride affinity support.
Washington University School of Medicine, Department of Medicine, St. Louis, Missouri 63110.
W R
WR
Ross
W S
WS
Bertrand
A R
AR
Morrison
D000584:Amiloride / Q000031:analogs & derivatives / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D018833:Chaperonins; D002846:Chromatography, Affinity; D006360:Heat-Shock Proteins / Q000737:chemistry*; D007668:Kidney / Q000737:chemistry*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D011719:Pyrazines / Q000378:metabolism
D006360:Heat-Shock Proteins; D010446:Peptide Fragments; D011506:Proteins; D011719:Pyrazines; D000584:Amiloride; D018833:Chaperonins