Endoplasmic reticulum of rat liver contains two proteins related to skeletal sarcoplasmic reticulum Ca-ATPase and calsequestrin

Journal Article · Tue Jan 05 00:00:00 EST 1988 · J. Biol. Chem.; (United States)

OSTI ID:6924809

Damiani, E; Spamer, C; Heilmann, C; Salvatori, S; Ma, A

Rat liver endoplasmic reticulum (ER) membranes were investigated for the presence of proteins having structural relationships with sarcoplasmic reticulum (SR) proteins. Western immunoblots of ER proteins probed with polyclonal antibodies raised against the 100-kDa SR Ca-ATPase of rabbit skeletalmuscle identified a single reactive protein of 100 kDa. Also, the antibody inhibited up to 50% the Ca-ATPase activity of isolated ER membranes. Antisera raised against the major intraluminal calcium binding protein of rabbit skeletal muscle SR, calsequestrin (CS), cross-reacted with an ER peptide of about 53 kDa, by the blotting technique. Strains-All treatment of slab gels showed that the cross-reactive peptide stained metachromatically blue, similarly to SR CS. Two-dimensional electrophoresis of ER proteins showed that CS-like component of liver ER, similarly to skeletal CS, fell off the diagonal line, as expected from the characteristic pH dependence of the rate of mobility of mammalian CS. In addition, the CS-like component of liver ER was released from the vesicles by alkaline treatment and was found to be able to bind calcium, by a /sup 45/Ca overlay technique. From these finding, the authors conclude that a 100-kDa membrane protein of liver ER is the Ca-ATPase, and that the peripheral protein in the 63-kDa range is closely structurally and functionally related to skeletal CS.

• Research Organization: Institute of General Pathology, Padova (Italy)
• OSTI ID: 6924809
• Journal Information: J. Biol. Chem.; (United States), Vol. 263:1
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CALCIUM 45
TRACER TECHNIQUES
ENDOPLASMIC RETICULUM
MOLECULAR STRUCTURE
SARCOPLASMIC RETICULUM
ATP-ASE
CALCIUM CHLORIDES
LIVER
PROTEINS
RATS
TWO-DIMENSIONAL ELECTROPHORESIS
ACID ANHYDRASES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CALCIUM COMPOUNDS
CALCIUM HALIDES
CALCIUM ISOTOPES
CELL CONSTITUENTS
CHLORIDES
CHLORINE COMPOUNDS
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
ELECTROPHORESIS
ENZYMES
EVEN-ODD NUCLEI
GLANDS
HALIDES
HALOGEN COMPOUNDS
HYDROLASES
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
NUCLEI
ORGANIC COMPOUNDS
ORGANOIDS
ORGANS
PHOSPHOHYDROLASES
RADIOISOTOPES
RODENTS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques