+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

The endoplasmic reticulum-sarcoplasmic reticulum connection: distribution of endoplasmic reticulum markers in the sarcoplasmic reticulum of skeletal muscle fibers

The endoplasmic reticulum-sarcoplasmic reticulum connection: distribution of endoplasmic reticulum markers in the sarcoplasmic reticulum of skeletal muscle fibers

Proceedings of the National Academy of Sciences of the United States of America 89(13): 6142-6146

The skeletal muscle sarcoplasmic reticulum (SR) was investigated for the presence of well-known endoplasmic reticulum (ER) markers: the lumenal protein BiP and a group of membrane proteins recognized by an antibody raised against ER membrane vesicles. Western blots of SR fractions revealed the presence of BiP in fast- and slow-twitch muscles of the rabbit as well as in rat and chicken muscles. Analyses of purified SR subfractions, together with cryosection immunofluorescence and immunogold labeling, revealed BiP evenly distributed within the longitudinal SR and the terminal cisternae. Within the terminal cisternae BiP appeared not to be mixed with calsequestrin but to be distributed around the aggregates of the latter Ca2+ binding protein. Of the various membrane markers only calnexin (91 kDa) was found to be distributed within both SR subfractions, whereas the other markers (apparent molecular masses of 64 kDa and 58 kDa and a doublet around 28 kDa) were concentrated in the terminal cisternae. These results suggest that the SR is a specialized ER subcompartment in which general markers, such as the ones we have investigated, coexist with the major SR proteins specifically responsible for Ca2+ uptake, storage, and release. The differential distribution of the ER markers reveals new aspects of the SR molecular structure that might be of importance for the functioning of the endomembrane system.

Please choose payment method:

(PDF emailed within 0-6 h: $19.90)

Accession: 041646191

Download citation: RISBibTeXText

PMID: 1631100

DOI: 10.2307/2359509

Related references

The endoplasmic reticulum-sarcoplasmic reticulum connection. II. Postnatal differentiation of the sarcoplasmic reticulum in skeletal muscle fibers. Experimental Cell Research 209(1): 140-148, 1993

Distribution of the endoplasmic reticulum and its relationship with the sarcoplasmic reticulum in skeletal myofibers. Experimental Cell Research 289(1): 57, 2003

Interrelationships among golgi apparatus rough endoplasmic reticulum and sarcoplasmic reticulum in skeletal muscle cells in primary culture. Journal of Cell Biology 75(2 PART 2): 329A, 1977

Bip and p91 calnexin two lumenal and membrane proteins of the endoplasmic reticulum are expressed in the skeletal muscle sarcoplasmic reticulum of rabbit and other species. Biophysical Journal 61(2 PART 2): A422, 1992

Enrichment of endoplasmic reticulum with cholesterol inhibits sarcoplasmic-endoplasmic reticulum calcium ATPase-2b activity in parallel with increased order of membrane lipids: implications for depletion of endoplasmic reticulum calcium stores and apoptosis in cholesterol-loaded macrophages. Journal of Biological Chemistry 279(35): 37030-9, 2004

Endoplasmic reticulum and sarcoplasmic reticulum of skeletal myofibers are separate compartments. Molecular Biology of the Cell 11(Suppl.): 417a, 2000

Monoclonal antibodies to dog heart sarcoplasmic reticulum as markers of endoplasmic reticulum. Journal of Molecular and Cellular Cardiology 21 Suppl 1: 55-58, 1989

Vesicle budding from endoplasmic reticulum is involved in calsequestrin routing to sarcoplasmic reticulum of skeletal muscles. Biochemical Journal 379(Pt 2): 505-512, 2004

Endoplasmic reticulum of rat liver contains two proteins closely related to skeletal sarcoplasmic reticulum Ca-ATPase and calsequestrin. Journal of Biological Chemistry 263(1): 340-343, 1988

Microdomains of endoplasmic reticulum within the sarcoplasmic reticulum of skeletal myofibers. Experimental Cell Research 314(2): 237-245, 2007

Excessive sarcoplasmic/endoplasmic reticulum Ca2+-ATPase expression causes increased sarcoplasmic reticulum Ca2+ uptake but decreases myocyte shortening. Circulation 110(23): 3553-3559, 2004

Effects of phytoestrogens on sarcoplasmic/endoplasmic reticulum calcium ATPase 2a and Ca2+ uptake into cardiac sarcoplasmic reticulum. Journal of Pharmacology and Experimental Therapeutics 316(2): 628-635, 2005

Alisol B, a novel inhibitor of the sarcoplasmic/endoplasmic reticulum Ca(2+) ATPase pump, induces autophagy, endoplasmic reticulum stress, and apoptosis. Molecular Cancer Therapeutics 9(3): 718-730, 2010

Ionic permeability of isolated muscle sarcoplasmic reticulum and liver endoplasmic reticulum vesicles. Methods in Enzymology 157: 417-437, 1988

Osmium deposition specific to smooth endoplasmic reticulum of insect photoreceptors and sarcoplasmic reticulum of muscle. Investigative Ophthalmology & Visual Science 32(4): 1151, 1991