杂种优势的一种可能的分子机理——杂合酶的协同效应  

A Possible Molecular Mechanism of Heterosis ——Concerted Effect of Heterozyme

作　　者：谭远德[1] 

机构地区：[1]南京师范大学生物系

出　　处：《南京师大学报（自然科学版）》1998年第3期80-87,共8页Journal of Nanjing Normal University(Natural Science Edition)

摘　　要：根据酶的结构与催化功能关系原理，提出了杂种优势的一种分子机理的假设，即杂合酶的协同效应，显性互补和异质等位基因互补是其中两个特例．应用杂合酶的正负协同效应能够很好地解释杂种优势的正负性和强弱性．杂合酶的特性与杂种优势的许多性质是一致的．杂合酶的活性多态性得到了同工酶的验证，其中的杂合酶活性强度与杂种优势有很强的正相关．从多聚酶的亚基间相互作用所产生的构象变化的传递形成的催化反应的协同性，讨论了杂合酶产生协同效应的可能性，以及与杂种优势之间的关系．已有许多间接证据暗示基因→酶→协同效应→杂种优势这机制存在的可能性．A hypothesis of molecular mechanism of heterosis,the concerted effect of heterozyme,was suggested in light of the relationship between function and structure of enzyme in this paper. The positive and negative concerted effects of heterozymes can be applied reasonably to interpret the positiveness and negativeness of heterosis and their intensity. There are many identical characters between heteroenzyme and heterosis. Active polymorphism of heterozyme has been testified by investigation of isozyme or allozyme. Many results suggested that intensity of activation of heterozyme from isozymes be highly correlated to heterosis.From the catalytic concert produced by the transfer of conformation change that results from reaction among subunits of a heterozyme,we discussed the possibility of the concerted effect among subunits of a heteroenzyme and their correlation to heterosis. Now there is this possibility in many evidents for the molecular mechanism:gene→enzyme→concerted effect→heterosis.

关 键 词：杂种优势 杂合酶 协同效应 分子机理 

分 类 号：Q321.6[生物学—遗传学]