Molecular mechanisms of morphogenesis and response to environmental cues in cladoceran crustaceans

枝角类甲壳动物形态发生和对环境信号响应的分子机制

基本信息

批准号：
18570093
负责人：
YAMAGATA Hideo
金额：
$ 2.53万
依托单位：
Tokyo University of Pharmacy and Life Science
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18570093/
关键词：
plankton ecology gene development and differentiation reproduction cycle 生物圏現象多様性発生・文化

项目摘要

Abundant expression of transcriptional read through products of two adjacent Hox genes, Ubx and Antp, was found in five crustacean species of Branchiopoda and Malacostaraca. In Daphnia, bicistronic Ubx/Antp mRNA produced no significant level of either Ubx or ANTP. In Artemia, on the other hand, the bicistronic mRNA produced only Ubx, and replaced the role of monocistronic Ubx mRNA. In this way, multiple post-transcriptional control mechanic ms in two extant branchiopodans can be seen as preventing the potentially deleterious consequences of fox gene fusion.Expression of D. magna aryl hydrocarbon receptor nuclear translocator (ARNT) in ARNT-lacking mouse Hepa-c4 cells resulted in the compensation for the loss of hypoxia response. D. magna ARNT was expressed in various tissues at the middle to late stages of embryonic development. In contrast, expression of ARNT in adult daphnids was limited to the epipodites of thoracic limbs, suggesting that ARNT plays a role solely in hypoxia response. Juvenile hormone (JH) agonists, pyriproxyfen and fenoxycarb, strongly repressed the expression of vitellogenin genes in neonate daphnids. The intergenic region of 2.6 kb between the D. magna vitellogenin genes contained sequences resembling known JH-responsive and ecdysone-responsive elements. A D. magna cDNA homolog of CPEB, a sex-determinant in C. elegans, was isolated and characterized. Amount of CPEB mRNA was decreased to one seventh after exposure of daphnids to JH. CPEB mRNA was expressed specifically in germ line cells in daphnids at the stages of yolk formation. Subunit composition of hemoglobins induced by exposure of daphnids to JH was different from that of hemoglobins induced by hypoxia.

在鳃足纲和软体动物的五种甲壳类动物中发现了两个相邻 Hox 基因 Ubx 和 Antp 的转录读取产物的大量表达。在水蚤中，双顺反子 Ubx/Antp mRNA 不产生显着水平的 Ubx 或 ANTP。另一方面，在卤虫中，双顺反子 mRNA 只产生 Ubx，并取代了单顺反子 Ubx mRNA 的作用。通过这种方式，两种现存鳃足动物中的多种转录后控制机制可以被视为防止 Fox 基因融合的潜在有害后果。 D. magna 芳基碳氢化合物受体核易位子 (ARNT) 在 ARNT 缺乏小鼠 Hepa-c4 中的表达细胞导致缺氧反应损失的代偿。 D. magna ARNT在胚胎发育中后期的多种组织中表达。相比之下，成年水蚤中 ARNT 的表达仅限于胸肢的上足，表明 ARNT 仅在缺氧反应中发挥作用。保幼激素 (JH) 激动剂吡丙醚和苯氧威强烈抑制新生水蚤中卵黄蛋白原基因的表达。 D. magna 卵黄蛋白原基因之间 2.6 kb 的基因间区域包含类似于已知的 JH 响应元件和蜕皮激素响应元件的序列。分离并鉴定了 CPEB（线虫性别决定因子）的 D. magna cDNA 同源物。水蚤暴露于 JH 后，CPEB mRNA 的量减少至七分之一。 CPEB mRNA 在水蚤卵黄形成阶段的生殖系细胞中特异性表达。水蚤JH暴露引起的血红蛋白亚基组成与缺氧引起的血红蛋白亚基组成不同。