Gatica-Sosa Claudia, Brzęk Pawel, Magallanes Melisa, Karasov William H, Caviedes-Vidal Enrique
Departamento de Bioquímica y Ciencias Biológicas, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, 5700 San Luis, Argentina.
Department of Animal Ecology, Institute of Biology, University of Białystok, Ciołkowskiego 1J, 15-245 Białystok, Poland.
J Exp Biol. 2018 Mar 19;221(Pt 6):jeb171827. doi: 10.1242/jeb.171827.
We describe developmental changes in maltasic activity and its mRNA until adulthood, and in response to an increase in dietary starch. We studied house sparrows (), which undergo a natural switch from insects to a starch-containing seed diet during development, and zebra finches (), which have a relatively fixed starchy seed diet during development. In zebra finches, in which maltasic activity increased with age but not with dietary starch, α-glycosidase (AG) mRNA was not affected by either age or dietary starch level. In house sparrow nestlings, in which maltasic activity increased with age and with added starch, AG mRNA was higher when birds were fed a diet with added starch but did not increase with age. These results are consistent with the idea that the apparent programmed developmental increase in maltasic activity is not mainly under transcriptional control of AG mRNA, whereas induction of maltasic activity by increased dietary starch is.
我们描述了直至成年期的麦芽糖酶活性及其信使核糖核酸（mRNA）的发育变化，以及对膳食淀粉增加的反应。我们研究了家麻雀（），它们在发育过程中会从以昆虫为食自然转变为以含淀粉种子为食，还研究了斑胸草雀（），它们在发育过程中食用相对固定的含淀粉种子食物。在斑胸草雀中，麦芽糖酶活性随年龄增长而增加，但不随膳食淀粉增加而增加，α - 糖苷酶（AG）mRNA不受年龄或膳食淀粉水平的影响。在家麻雀雏鸟中，麦芽糖酶活性随年龄增长以及添加淀粉而增加，当给雏鸟喂食添加了淀粉的食物时，AG mRNA水平较高，但不随年龄增加。这些结果与以下观点一致：麦芽糖酶活性明显的程序性发育增加主要不受AG mRNA转录控制，而膳食淀粉增加诱导麦芽糖酶活性则受其控制。
