• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Broad Complex evolution, function and expression: Insights from tissue reorganization during metamorphosis.
【24h】

Broad Complex evolution, function and expression: Insights from tissue reorganization during metamorphosis.

机译：广泛的复杂进化，功能和表达：在变态过程中组织重组的见解。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Broad Complex (BRC) is an ecdysone-pathway gene essential for entry into and progression through metamorphosis in D. melanogaster. Mutations of three BRC complementation groups cause numerous phenotypes, including a common suite of morphogenesis defects involving central nervous system (CNS), adult salivary glands (aSG), and male genitalia. Alternative splicing, of a protein-binding BTB-encoding exon (BTBBRC) to one of four tandemly duplicated, DNA-binding zinc-finger-encoding exons (Z1BRC, Z2 BRC, Z3BRC, Z4BRC), produces four BRC isoforms. Highly conserved orthologs of BTBBRC and all four ZBRC were found in silico from Diptera, Lepidoptera, Hymenoptera and Coleoptera, indicating that BRC arose and underwent internal exon duplication before the split of holometalolous orders. Five Tramtrack subfamily members were characterized throughout Holometabola and used to root phylogenetic analyses of ZBRC exons, revealing that Z3BRC is the basal member. All four ZBRC domains, including Z4BRC which has no known essential function, are evolving in a manner consistent with selective constraint. Transgenic rescue and immunohistochemistry were used to explore how different BRC isoforms contribute to their shared tissue-morphogenesis functions at the onset of metamorphosis, when BRC is required for CNS reorganization. As predicted, the common CNS and aSG phenotypes were rescued by BRC-Z1 in rbp mutants, BRC-Z2 in br mutants, and BRC-Z3 in 2Bc mutants. However, the isoforms are required at two developmental stages, with BRC-Z2 and -Z3 required earlier than BRC-Z1. Each isoform had a unique expression pattern in the CNS, with no substantial three-way overlap among them. Z4 is strongly expressed in a novel subset of CNS neurons. The 7 most prominent localizations of BRC-Z1, -Z2, -Z3 corresponded with glia, neuroblasts and neurons, respectively. There appears to be a switch from BRC-Z2 in proliferating cells to BRC-Z1 and BRC-Z3 in differentiating cells. The temporal-requirement and spatial-distribution data suggest that BRC-dependent CNS morphogenesis is the result of multicellular interactions among different cell types at different times. BRC-Z1-expressing glia in prepupae may mediate the final steps of CNS morphogenesis. Lastly, BRC is required for migration and programmed cell death of the ring gland, the site of ecdysone and juvenile hormone production. Therefore, BRC may function in ecdysone auto-regulation.
机译：宽复合体（Broad Complex，BRC）是蜕皮激素途径基因，对于黑腹果蝇（D. melanogaster）的进入和通过蜕变的进行至关重要。三个BRC互补组的突变会导致许多表型，包括涉及中枢神经系统（CNS），成年唾液腺（aSG）和男性生殖器的常见形态发生缺陷。蛋白质结合BTB编码外显子（BTBBRC）与四个串联重复的DNA结合锌指编码外显子（Z1BRC，Z2 BRC，Z3BRC，Z4BRC）之一的选择性剪接产生四个BRC亚型。在双翅目，鳞翅目，膜翅目和鞘翅目的计算机中发现了高度保守的BTBBRC直系同源物和所有四个ZBRC直系同源物，这表明BRC出现并在全金属质序分裂之前经历了内部外显子重复。在整个Holometabola中对五个Tramtrack亚家族成员进行了表征，并将其用于ZBRC外显子的根系统发育分析，从而揭示Z3BRC是基础成员。所有四个ZBRC域，包括没有已知基本功能的Z4BRC，都以与选择性约束一致的方式发展。当CNS重组需要BRC时，使用转基因拯救和免疫组织化学研究了不同的BRC亚型在变态开始时如何促进它们共有的组织形态发生功能。如预期的那样，常见的CNS和aSG表型通过rbp突变体中的BRC-Z1，br突变体中的BRC-Z2和2Bc突变体中的BRC-Z3拯救。但是，在两个发育阶段都需要同工型，其中BRC-Z2和-Z3比BRC-Z1早。每个同工型在CNS中都有独特的表达模式，它们之间没有实质性的三向重叠。 Z4在中枢神经系统神经元的新子集中强烈表达。 BRC-Z1，-Z2，-Z3的7个最突出的位置分别对应于胶质细胞，成神经细胞和神经元。似乎从增殖细胞中的BRC-Z2转向分化细胞中的BRC-Z1和BRC-Z3。时间要求和空间分布数据表明，依赖BRC的CNS形态发生是不同时间不同细胞类型之间多细胞相互作用的结果。 pre中表达BRC-Z1的胶质细胞可能介导CNS形态发生的最终步骤。最后，BRC对于环腺，蜕皮激素和少年激素产生的部位的迁移和程序性细胞死亡是必需的。因此，BRC可能在蜕皮激素自动调节中起作用。

著录项

  • 作者

    Spokony, Rebecca Fran.;

  • 作者单位

    The University of Arizona.;

  • 授予单位 The University of Arizona.;
  • 学科 Biology Entomology.; Biology Genetics.; Biology Animal Physiology.; Health Sciences Pathology.; Biology Physiology.
  • 学位 Ph.D.
  • 年度 2007
  • 页码 197 p.
  • 总页数 197
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 昆虫学;遗传学;生理学;病理学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号