Jones G, Venkataraman V, Manczak M, Schelling D
School of Biological Sciences, University of Kentucky, Lexington 40506.
Dev Genet. 1993;14(4):323-32. doi: 10.1002/dvg.1020140410.
Proteins normally expressed in high abundance only at larval-pupal metamorphosis in Trichoplusia ni were examined in a comparative analysis of the role and level of hormonal control of their expression. Some related proteins in the hemocyanin-superfamily (i.e., an acidic protein [AJHSP1] and two basic proteins [BJHSP1, BJHSP2]) were shown by nuclear run-on analysis to be specifically transcriptionally suppressed by juvenile hormone (JH), while transcription of another member of that family which is also metamorphosis-associated (arylphorin) was not specifically sensitive to JH. The stability of the mRNA for those members transcriptionally down-regulated by JH appeared to decrease under high JH conditions. While each protein was resorbed to some extent by the prepupal fat body, only the two basic proteins were quantitatively cleared from prepupal hemolymph. The JH-sensitive proteins studied appear to be encoded in single copy genes not immediately juxtaposed in the genome. These and previous studies now permit a more comprehensive understanding of the different combinations of mechanisms involving transcription, mRNA stability, translation, and protein clearance that operate to regulate these metamorphosis-associated proteins.
在对棉铃虫幼虫-蛹变态过程中正常高丰度表达的蛋白质进行的比较分析中，研究了其表达的激素控制作用和水平。核转录分析表明，血蓝蛋白超家族中的一些相关蛋白质（即一种酸性蛋白[AJHSP1]和两种碱性蛋白[BJHSP1、BJHSP2]）受到保幼激素（JH）的特异性转录抑制，而该家族中另一种与变态相关的成员（芳基蛋白）的转录对JH不敏感。在高JH条件下，那些被JH转录下调的成员的mRNA稳定性似乎降低。虽然每种蛋白质在化蛹前脂肪体中都有一定程度的再吸收，但只有两种碱性蛋白从化蛹前血淋巴中被定量清除。所研究的对JH敏感的蛋白质似乎由基因组中不紧邻的单拷贝基因编码。这些研究以及之前的研究现在使我们能够更全面地理解涉及转录、mRNA稳定性、翻译和蛋白质清除的不同机制组合，这些机制共同作用来调节这些与变态相关的蛋白质。
