Population genetics of Drosophila amylase. IV. Selection in laboratory populations maintained on different carbohydrates.
Population genetics of Drosophila amylase. IV. Selection in laboratory populations maintained on different carbohydrates.
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果蝇淀粉酶的群体遗传学。
DOI：
10.1093/genetics/103.4.675
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发表时间：
1983
期刊：
影响因子：
3.3
通讯作者：
Marko Andjelkovic
中科院分区：
文献类型：
--
作者：
Jeffrey R. Powell;Marko Andjelkovic
两个多态性系统碰撞的α-淀粉酶在果蝇pseudobscura进行了研究，在实验室种群保持在培养基中，其中唯一的碳水化合物源是淀粉（淀粉酶的底物）和复制品保持在培养基中，其中唯一的碳水化合物源是麦芽糖（淀粉酶的产物）。这两个多态性系统的等位基因的结构基因（艾米）编码的酶（等位酶）和变化的组织特异性表达沿着成人中肠由几个基因控制。在麦芽糖培养基上的七个种群中，在两个系统中都没有注意到一致的变化。在淀粉培养基上的7个群体中，两种多态性均表现出选择性变化。中肠模式的非常有限的淀粉酶的表达上升的频率在所有的淀粉人口，如频率的“快”（1.00）艾米等位基因。总的比淀粉酶活性在适应淀粉和适应麦芽糖的果蝇之间没有差异。沿着先前的研究结果表明，当基因-酶系统在实验室人群中受到特异性应激时，等位酶往往表现出选择性差异。这样的结果至少使选择论假说站得住脚。此外，这两种类型的多态性对选择的反应表明，在适应性进化中结构基因与基因调控变化的作用不是一个非此即彼的问题，而是一个相对的作用和相互作用。
Two polymorphic systems impinging on alpha-amylase in Drosophila pseudoobscura have been studied in laboratory populations maintained on medium in which the only carbohydrate source was starch (the substrate of amylase) and replicas maintained on medium in which the only carbohydrate source was maltose (the product of amylase). The two polymorphic systems were alleles at the structural gene (Amy) coding for the enzyme (allozymes) and variation in the tissue-specific expression along the adult midgut controlled by several genes. In the seven populations on maltose medium little consistent change was noted in either system. In the seven populations on starch medium, both polymorphisms exhibited selective changes. A midgut pattern of very limited expression of amylase rose in frequency in all starch populations, as did the frequency of the "fast" (1.00) Amy allele. The overall specific amylase activity did not differ between starch-adapted and maltose-adapted flies.--The results, along with previous studies, indicate that when a gene-enzyme system is specifically stressed in laboratory populations, allozymes often exhibit selective differences. Such results make the selectionist hypothesis at least tenable. Furthermore, the fact that both types of polymorphisms responded to selection indicates the role of structural gene vs. gene regulation changes in adaptive evolution is not an either/or question but one of relative roles and interactions.