Density-dependent modulation of vascular smooth muscle alpha-actin biosynthetic processing in differentiated BC3H1 myogenic cells.
Density-dependent modulation of vascular smooth muscle alpha-actin biosynthetic processing in differentiated BC3H1 myogenic cells.
复制标题
分化的 BC3H1 生肌细胞中血管平滑肌 α-肌动蛋白生物合成加工的密度依赖性调节。
DOI：
10.1002/jcb.240500307
复制
发表时间：
1992
影响因子：
4
通讯作者：
Berman,MD
中科院分区：
文献类型：
--
作者：
Strauch,AR;Min,B;Reeser,JC;Yan,H;Foster,DN;Berman,MD
高细胞密度条件会特别刺激 BC3H1 肌原细胞分化过程中血管平滑肌 (VSM) α-肌动蛋白 mRNA 的表达。使用 EDTA 对 BC3H1 肌细胞汇合后培养物中的细胞-细胞和细胞-基质接触进行非蛋白水解解离，促进分化形态表型的丧失。 EDTA 分散的肌细胞表现出未分化的成纤维细胞外观，并且 VSM 和骨骼 α-肌动蛋白 mRNA 的水平降低。通过细胞密度条件的实验操作，EDTA 分散的心肌细胞中的肌肉 α-肌动蛋白 mRNA 水平并未恢复到汇合心肌细胞制剂中观察到的水平。使用 L-[35S] 半胱氨酸的脉冲标记技术来鉴定肌肉肌动蛋白生物合成中间体，结果表明 EDTA 分散的肌细胞表达 VSM 和骨骼肌 α-肌动蛋白多肽链的新生形式。然而，与非分散的肌细胞相比，EDTA 分散的肌细胞在不成熟 VSM α-肌动蛋白的翻译后加工中效率较低。简单的细胞间接触可能会介导 VSM α-肌动蛋白处理效率，因为 EDTA 分散的心肌细胞的高密度制剂比低密度铺板的心肌细胞处理更多的 VSM α-肌动蛋白中间体。对细胞间接触调节的反应的肌动蛋白异构体选择性表明，BC3H1生肌细胞中的肌动蛋白生物合成涉及能够区分新生肌动蛋白多肽链的不同异构体类别的机制。 © 1992 Wiley-Liss, Inc.
The expression of vasuclar smooth muscle (VSM) α‐actin mRNA during BC3H1 myogenic cell differentiation is specifically stimulated by conditions of high cell density. Non‐proteolytic dissociation of cell‐cell and cell‐matrix contacts in post‐confluent cultures of BC3H1 myocytes using EDTA promotes loss of the differentiated morphological phenotype. EDTA‐dispersed myocytes exhibit an undifferentiated fibroblastoid appearance and contained reduced levels of both VSM and skeletal α‐actin mRNA. Muscle α‐actin mRNA levels in EDTA‐dispersed myocytes were not restored to that observed in confluent myocyte preparations by experimental manipulation of cell density conditions. Pulse‐labeling techniques using L‐[35S] cysteine to identify muscle actin biosynthetic intermediates revelated that EDTA‐dispersed myocytes expressed nascent forms of both the VSM and skeletal muscle α‐actin polypetide chains. However EDTA‐dispersed myocytes were less effieicent in the post‐translational processing of immautre VSM α‐actin compared to non‐dispersed myocytes. Simple cell‐to‐cell contact may mediate VSM α‐actin processing efficiency since high‐density preparations of EDTA‐dispersed myocytes processed more VSM α‐actin intermediate than myocytes plated at low density. The actin isoform selectivity of the response to modulation of intercellular contacts suggests that actin biosynthesis in BC3H1 myogenic cells involves mehcanisms capable of discriminating between different isoform classes of nascent actin polypetide chains. © 1992 Wiley‐Liss, Inc.