Immunological localization of ribosomes in striated rat muscle. Evidence for myofibrillar association and ontological changes in the subsarcolemmal:myofibrillar distribution.
Ribosome distribution in skeletal-muscle fibres was investigated immunohistochemically by using polyclonal antibodies raised against large-ribosomal-subunit proteins isolated from rat liver. Immunoblot analysis showed the antibodies to recognize five major proteins of the large subunit; these were identified as L4, L6, L7, L15 and L17 by two-dimensional electrophoresis. Immunohistochemistry of frozen rat skeletal-muscle sections showed staining of both the subsarcolemmal and intermyofibrillar cytoplasm. A distinct banding pattern was observed, and when peroxidase and phase-contrast images of the same field were compared by image analysis the anti-ribosome staining was found to correspond to the A-bands. These results suggest that a proportion of muscle ribosomes are present in the myofibrillar cytoplasm in a regular fashion, possibly associated with myosin. Densitometric analysis of the peroxidase immunostaining showed that the ratio of myofibrillar to sub-sarcolemmal ribosomal material was lower in muscle from 51-day-old rats compared with those from 14-day-old animals.
Biochemistry Division, Rowett Research Institute, Bucksburn, Aberdeen, U.K.
Z
Z
Horne
J
J
Hesketh
D000375:Aging; D000818:Animals; D003593:Cytoplasm / Q000648:ultrastructure; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D008297:Male; D008970:Molecular Weight; D024510:Muscle Development; D009132:Muscles / Q000648:ultrastructure; D009210:Myofibrils / Q000648:ultrastructure*; D051381:Rats; D012269:Ribosomal Proteins / Q000032:analysis; D012270:Ribosomes / Q000032:analysis / Q000648:ultrastructure*; D012508:Sarcolemma / Q000648:ultrastructure*
D012269:Ribosomal Proteins