Baydoun E A, Northcote D H
J Cell Sci. 1980 Oct;45:169-86. doi: 10.1242/jcs.45.1.169.
Maize root tips were incubated in vivo with radioactive glucose, choline or diazotized sulphanilic acid. Membrane fractions were prepared from radioactive and non-radioactive roots. The transfer of radioactivity between mixed membrane fractions has enabled a quantitative system to be developed to study in vitro membrane fusion between Golgi apparatus and plasma membrane-rich fractions. Membrane fusion was found to be dependent on time, temperature, Mn2+ and Ca2+. Mn2+ was as effective as Ca2+, other divalent cations had a moderate or no effect. The effect of various substances, including inhibitors of microtubular and microfilament assembly and blocking reagents for sulphydryl group on membrane fusion has been investigated. The process appears to be dependent on the membrane proteins or glycoproteins; trypsinization of mixed membranes prior to the addition of Ca2+ inhibited significantly the fusion process. SDS-polyacrylamide gel electrophoresis of trypsin-treated membranes revealed the selective loss of one particular polypeptide which could play a role in membrane fusion.
将玉米根尖在体内与放射性葡萄糖、胆碱或重氮化磺胺酸一起孵育。从放射性和非放射性根中制备膜组分。混合膜组分之间放射性的转移使得能够开发出一种定量系统，用于研究高尔基体与富含质膜的组分之间的体外膜融合。发现膜融合取决于时间、温度、Mn2+和Ca2+。Mn2+与Ca2+一样有效，其他二价阳离子有中等作用或无作用。研究了包括微管和微丝组装抑制剂以及巯基封闭试剂在内的各种物质对膜融合的影响。该过程似乎取决于膜蛋白或糖蛋白；在添加Ca2+之前对混合膜进行胰蛋白酶处理会显著抑制融合过程。对经胰蛋白酶处理的膜进行SDS-聚丙烯酰胺凝胶电泳显示，一种特定的多肽选择性丢失，该多肽可能在膜融合中起作用。
