Developmental regulation of multiple forms of UDPglucose pyrophosphorylase of Dictyostelium.
Developmental regulation of multiple forms of UDPglucose pyrophosphorylase of Dictyostelium.
复制标题
盘基网柄菌多种形式的UDP葡萄糖焦磷酸化酶的发育调控。
DOI：
10.1016/0012-1606(82)90161-0
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发表时间：
1982
影响因子：
2.7
通讯作者：
Dottin,RP
中科院分区：
文献类型：
--
作者：
Fishel,BR;Manrow,RE;Dottin,RP
尿苷二磷酸葡萄糖焦磷酸化酶（UTP：α-d-glucose-1-phosphate uridylyltransferase，EC 2.7.7.9）是盘基网柄藻中一种发育调节酶，对盘基网柄藻生命周期的完成至关重要。在营养生长和分化的早期阶段，酶的比活性保持恒定。然而，到子实体形成时，它会增加三倍。我们已经确定了一种发育特异性形式的尿苷二磷酸葡萄糖焦磷酸化酶，改变在两个等电点和表观分子量，通过解决二维变性聚丙烯酰胺凝胶上的细胞粗提物，原位复性的蛋白质，并定位活性酶与组织化学染色。对凝胶中沉积的酶染色量的定量显示，新形式的活性可以解释在发育中观察到的增加。酶的发育形式的出现需要novoprotein合成，因为它被放线菌酮抑制。免疫沉淀尿苷二磷酸葡萄糖焦磷酸化酶从体内和体外合成的蛋白质揭示了异质性以前没有检测到的酶从营养和发达的细胞。两种不同的蛋白质在体外由营养细胞或发育细胞的mRNA合成。这两种蛋白质也存在于体内发育的细胞中。这两种蛋白质中只有一种存在于营养细胞中。体内合成的酶蛋白在翻译后似乎被修饰。因此，观察到的异质性尿苷二磷酸葡萄糖焦磷酸化酶foundin vivoappears由于翻译后修饰和从一个或多个物种的mRNA的两个多肽的合成。
Uridine diphosphoglucose pyrophosphorylase (UTP:α-d-glucose-1-phosphate uridylyltransferase, EC 2.7.7.9) is a developmentally regulated enzyme inDictyostelium discoideumessential for the completion of its life cycle. During vegetative growth and the early stages of differentiation the specific activity of the enzyme remains constant. However, it increases threefold by the time fruiting bodies are formed. We have identified a developmentally specific form of uridine diphosphoglucose pyrophosphorylase, altered in both isoelectric point and apparent molecular weight, by resolving crude extracts of cells on two-dimensional denaturing polyacrylamide gels, renaturing the proteinin situ, and localizing active enzyme with a histochemical stain. Quantitation of the amount of enzyme stain deposited in the gels shows that the activity in the new form can account for the increase observed in development. The appearance of the developmental form of the enzyme requiresde novoprotein synthesis since it is inhibited by cycloheximide. Immunoprecipitation of uridine diphosphoglucose pyrophosphorylase fromin vivoandin vitrosynthesized proteins has revealed heterogeneity not previously detected in the enzyme from both vegetative and developed cells. Two different proteins are synthesizedin vitroby mRNA from either vegetative or developed cells. These two proteins are also foundin vivoin developed cells. Only one of the two proteins is found in vegetative cells. Enzyme protein synthesizedin vivoappears to be modified after translation. Therefore, the observed heterogeneity in uridine diphosphoglucose pyrophosphorylase foundin vivoappears due both to post-translational modification and to synthesis of two polypeptides from one or more species of mRNA.