Genomics Laboratory, Seribiotech Research Laboratory, Carmelaram Post, Kodathi, Bangalore 560 035, India.
Comp Biochem Physiol B Biochem Mol Biol. 2012 Apr;161(4):371-9. doi: 10.1016/j.cbpb.2012.01.002. Epub 2012 Jan 10.
Molecular mechanism controlling egg diapause remains obscure in silkworm, Bombyx mori. An attempt is made to decipher various molecular events occurring during embryonic diapause in multivoltine silkworm, B. mori. Using suppressive subtractive hybridization (SSH), 186 cDNA clones isolated from both diapause and nondiapause eggs were sequenced. Of the sequenced clones, 29 matched with silkbase entries and these identified putative genes were classified into six functional groups such as regulatory, food utilization, stress response, metabolic, ribosomal and transposable elements. Among these genes, twelve belonged to regulatory group while, one taste receptor type 2 member 117 gene was related to food utilization. One heat shock cognate 70 kDa protein and 3 of the ubiquitin family were identified under stress response category. Similarly, four genes were identified as metabolic genes, 3 belonging to chitin family and one propanediol utilization protein. Of the seven genes identified in ribosomal groups, most of them were 60s ribosomal protein subunits. However, one negative regulation of transcription gene identified was a transposable element. The qPCR analysis confirmed the expression of 21 of the above genes, wherein, 6 were upregulated during diapause, 12 during non-diapause, while, 3 remained unchanged.
在蚕，家蚕中，控制卵滞育的分子机制仍然不清楚。本研究试图解析多化性家蚕胚胎滞育过程中发生的各种分子事件。利用抑制性消减杂交（SSH），从滞育和非滞育卵中分离出 186 个 cDNA 克隆进行测序。在测序的克隆中，有 29 个与 silkbase 条目匹配，这些鉴定出的假定基因被分为六个功能组，如调节、食物利用、应激反应、代谢、核糖体和转座元件。这些基因中，有 12 个属于调节组，而 1 个味觉受体 2 成员 117 基因与食物利用有关。在应激反应类别中鉴定出一个热休克同源 70kDa 蛋白和 3 个泛素家族蛋白。同样，鉴定出 4 个代谢基因，3 个属于几丁质家族，1 个丙二醇利用蛋白。在核糖体组中鉴定出的 7 个基因中，大多数是 60s 核糖体蛋白亚基。然而，鉴定出的一个转录负调控基因是一个转座元件。qPCR 分析证实了上述 21 个基因中的 21 个表达情况，其中 6 个在滞育期上调，12 个在非滞育期上调，而 3 个保持不变。
