Clark G F, Smith P B
Biochim Biophys Acta. 1983 Jan 4;755(1):56-64. doi: 10.1016/0304-4165(83)90272-6.
The postnatal development of mammalian skeletal muscle is characterized by changes in the properties of several key membrane glycoprotein enzymes and receptors. In the present study, CMP-sialic acid: fetuin sialyltransferase and CMP-sialic acid: lactosylceramide sialyltransferase activity was characterized in sarcolemma and sarcoplasmic reticulum membranes isolated from neonatal (0-1 week) and adult (8 week) rabbit skeletal muscle. CMP-sialic acid: fetuin sialyltransferase decreased by a factor of 10 in sarcolemma and 6 in sarcoplasmic reticulum during development, whereas CMP-sialic acid: lactosylceramide sialyltransferase activity decreased by a factor of 6 in sarcolemma and 18 in sarcoplasmic reticulum. The Km for CMP-sialic acid using the lipid acceptor declined during the development of sarcoplasmic reticulum (neonate vs. adult: 538 vs. 33 microM), but not in sarcolemma. The carbohydrate composition of sarcolemma was changed only with respect to total sialic acid content (neonate vs. adult: 67 vs. 44 nmol/mg). Similar analysis of sarcoplasmic reticulum carbohydrates showed decreases in total sialic acid, lipid-bound sialic acid, hexosamines and hexoses. The major ganglioside was GM3 for both types of membrane. No qualitative changes were observed in ganglioside composition comparing neonatal and adult membranes.
哺乳动物骨骼肌的出生后发育特征在于几种关键膜糖蛋白酶和受体的性质发生变化。在本研究中，对从新生（0 - 1周）和成年（8周）兔骨骼肌分离的肌膜和肌质网膜中的CMP - 唾液酸：胎球蛋白唾液酸转移酶和CMP - 唾液酸：乳糖神经酰胺唾液酸转移酶活性进行了表征。在发育过程中，肌膜中的CMP - 唾液酸：胎球蛋白唾液酸转移酶下降了10倍，肌质网中下降了6倍；而肌膜中的CMP - 唾液酸：乳糖神经酰胺唾液酸转移酶活性下降了6倍，肌质网中下降了18倍。在肌质网发育过程中（新生与成年：538对33μM），使用脂质受体时CMP - 唾液酸的Km值下降，但在肌膜中未下降。肌膜的碳水化合物组成仅在总唾液酸含量方面发生变化（新生与成年：67对44 nmol/mg）。对肌质网碳水化合物的类似分析表明，总唾液酸、脂质结合唾液酸、己糖胺和己糖减少。两种类型的膜中主要神经节苷脂均为GM3。比较新生和成年膜时，神经节苷脂组成未观察到定性变化。
