Characteristics of skeletal muscle tissue ribosomes
Khoroshkov, I.A.; Shishkin, S.S.
Biulleten' Eksperimental'noi Biologii i Meditsiny 81(5): 534-536
1976
ISSN/ISBN: 0365-9615 PMID: 947373 Document Number: 102837
Electron-microscopic and chemical analysis of the fraction of RNP-particles, samples of the muscle tissue of the posterior limb of rat and of the human musculus rectus abdominis was carried out for the purpose of characterizing ribosomes of the skeletomuscular tissue. RNP-particle fraction proved to contain functionally-active mono- and poly ribosomes. Two RNA fractions-- RNA1 and RAN11 were isolated. RNA1 proved to represent a set of ribosomic RNA with sedimentation coefficients 26-28S, 16-18S and 4-5S. RNA11 contained no ribosomal RNA, and by its nucleotide composition was affiliated to the nucleotide compostion of rat DNA. The structural organization of ribosomes in the cytoplasm of the muscular fibers corresponded to the pictures observed in the RNP-particle fraction. Polyribosomes are determined in the regions of physiological regeneration of myofibrillae and represent complexes consisting of 5 and more monoribosomes arranged in the form of beads. Ribosomes-like particles proved to escape through the nuclear menbrane; this fact, along with the data of chemical analysis pointed to the periodic passage of RNA from the nucleus into the cytoplasm of hte muscle fiber.