Morphological, immunological and biochemical characterization of purified transverse tubule membranes isolated from rabbit skeletal muscle.
A microsomal fraction consisting of membranes of transverse tubule origin has been purified by a modification of the calcium-loading procedure initially described by Rosemblatt et al. (J Biol Chem 256:8140-8, 1981). Enzymatic analysis of this fraction shows an enrichment of the vesicles in the Mg++ ATPase (basal) activity characteristic of the T-tubules and an absent or very low Ca++-dependent-ATPase activity. Stereological analysis of freeze fracture replica of the membranes in the purified fraction indicates that they have a very low density of particles in their P faces and lack the structural manifestation of the caveolae typical of the sarcolemma. Immunological analysis performed with monoclonal antibodies prepared against purified T-tubule and sarcoplasmic reticulum membranes define some T-tubule specific antigens and confirm the morphological and biochemical data regarding the origin and purity of the T-tubule preparation.
Rosemblatt
M S
MS
Laboratorio de Inmunología Celular, INTA, Universidad de Chile, Santiago, Chile.
Scales
D J
DJ
D000818:Animals; D000911:Antibodies, Monoclonal; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D002458:Cell Fractionation; D002462:Cell Membrane / Q000201:enzymology / Q000276:immunology / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D005614:Freeze Fracturing; D051379:Mice; D008807:Mice, Inbred BALB C; D008861:Microsomes / Q000201:enzymology / Q000276:immunology / Q000648:ultrastructure; D009124:Muscle Proteins / Q000032:analysis; D009132:Muscles / Q000201:enzymology / Q000276:immunology / Q000648:ultrastructure*; D011817:Rabbits; D012508:Sarcolemma / Q000201:enzymology / Q000276:immunology / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D009124:Muscle Proteins; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases; D002118:Calcium