Jiangsu University of Science and Technology, Zhenjiang, 212018, China.
Mol Biol Rep. 2014 Mar;41(3):1623-30. doi: 10.1007/s11033-013-3009-1. Epub 2014 Jan 8.
The gene encoding cathepsin D of silkworm, Bombyx mori (BmCatD) is specifically expressed in the larval fat body and pupal gut, and plays an important role in the programmed cell death during metamorphosis. To identify element involved in this transcription-dependent spatial restriction, truncation and deletion of the 5' terminal from the BmCatD promoter were conducted in vivo. The recombinant AcMNPV vector (Autographa californica multiple nucleopolyhedrovirus) with a dual-luciferase quantitative assay system was used as the transfer. A 289 bp DNA sequence (-1,214 to -925) upstream of the transcriptional start site is found to be responsible for promoting tissue-specific transcription. Further analysis of a series of deletion within the 289 bp region of overlapping deletion showed that a 33 bp region (-1,071 to -1,038) sequence suppresses the ectopic expression of the BmCatD promoter. These results suggest that this 33 bp region could function as a promoter element in the tissue-specificity expression.
家蚕组织蛋白酶 D 基因（BmCatD）特异性表达于幼虫脂肪体和蛹肠道，在变态过程中的程序性细胞死亡中发挥重要作用。为了鉴定参与这种转录依赖性空间限制的元件，对 BmCatD 启动子的 5'端进行了体内截断和缺失。携带双荧光素酶定量检测系统的重组 AcMNPV 载体（Autographa californica 多角体病毒）被用作转移载体。发现在转录起始位点上游的 289bp DNA 序列（-1,214 至-925）负责促进组织特异性转录。对重叠缺失的 289bp 区域内一系列缺失的进一步分析表明，33bp 区域（-1,071 至-1,038）序列抑制 BmCatD 启动子的异位表达。这些结果表明，该 33bp 区域可作为组织特异性表达中的启动子元件发挥作用。
