Takiya Shigeharu, Tsubota Takuya, Kimoto Mai
Shigeharu Takiya, Division of Biological Sciences and Center for Genome Dynamics, Faculty of Science, Hokkaido University, North 10, West 8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan.
Graduate School of Life Science, Hokkaido University, North 10, West 8, Kita-ku, Sapporo 060-0810, Japan.
J Dev Biol. 2016 May 25;4(2):19. doi: 10.3390/jdb4020019.
The silk gland of the silkworm is a long tubular organ that is divided into several subparts along its anteroposterior (AP) axis. As a trait of terminal differentiation of the silk gland, several silk protein genes are expressed with unique regional specificities. Most of the and some of the homeobox genes are also expressed in the differentiated silk gland with regional specificities. The expression patterns of genes in the silk gland roughly correspond to those in embryogenesis showing "colinearity". The central Hox class protein Antennapedia (Antp) directly regulates the expression of several middle silk gland-specific silk genes, whereas the Lin-1/Isl-1/Mec3 (LIM)-homeodomain transcriptional factor Arrowhead (Awh) regulates the expression of posterior silk gland-specific genes for silk fiber proteins. We summarize our results and discuss the usefulness of the silk gland of for analyzing the function of genes. Further analyses of the regulatory mechanisms underlying the region-specific expression of silk genes will provide novel insights into the molecular bases for target-gene selection and regulation by Hox and homeodomain proteins.
蚕的丝腺是一种长管状器官，沿其前后轴分为几个亚部分。作为丝腺终末分化的一个特征，几个丝蛋白基因以独特的区域特异性表达。大多数和一些同源异型盒基因也在分化的丝腺中具有区域特异性表达。丝腺中基因的表达模式大致与胚胎发生中的表达模式相对应，呈现出“共线性”。中枢同源异型基因类蛋白触角足蛋白（Antp）直接调节几个中丝腺特异性丝基因的表达，而Lin-1/Isl-1/Mec3（LIM）-同源异型结构域转录因子箭头蛋白（Awh）调节后丝腺特异性丝纤维蛋白基因的表达。我们总结了我们的结果，并讨论了蚕的丝腺对于分析基因功能的有用性。对丝基因区域特异性表达的调控机制的进一步分析将为Hox和同源异型结构域蛋白选择和调控靶基因的分子基础提供新的见解。
