• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Differential Transcriptional Modulation of Duplicated Fatty Acid-Binding Protein Genes by Dietary Fatty Acids in Zebrafish (Danio reno).
【24h】

Differential Transcriptional Modulation of Duplicated Fatty Acid-Binding Protein Genes by Dietary Fatty Acids in Zebrafish (Danio reno).

机译：日粮脂肪酸在斑马鱼中的复制脂肪酸结合蛋白基因的差异转录调节。

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

In the Duplication-Degeneration-Complementation (DDC) model, subfuctionalization and neofunctionalization have been proposed as major processes driving the retention of duplicated genes in the genome. These processes are thought to occur by gain or loss of regulatory elements in the promoters of duplicated genes. Many duplicated genes exist in teleost fishes as a result of a whole-genome duplication event that occurred early in the ray-finned fish lineage 250-400 million years ago. To test the DDC model, I chose to determine whether duplicated fatty acid-binding protein (fabp) genes are retained in the zebrafish genome owing to either subfunctionalization or neofunctionalization. I first determined the spatio-temporal distribution of transcripts for the fabp1b.2 and fabp11b genes by two methods: (i) in situ hybridization of riboprobes to embryos, larvae and sections of adult zebrafish, and (ii) reverse-transcription, polymerase chain reaction (RT-PCR) using RNA extracted from adult tissues. The results of these initial studies showed that the spatio-temporal distribution of duplicated copies for the fabp1 and fabp11 genes have markedly diverged. Furthermore, comparison of the spatio-temporal distribution of the duplicated copies of the zebra fish fabp1 and fabp11 genes with that of their single-copy mammalian orthologs indicated that the zebrafish fabp duplicates had been retained in the zebrafish genome owing to either subfunctionalization or neofuctionalization. In a second experimental approach to test the DDC model, transcriptional induction of duplicated zebrafish fabp genes by fatty acids (FAs), compounds known to induce the transcription of several mammalian fabp genes, was assayed by quantitative RT-PCR. Adult zebrafish fed four diets differing in FA content exhibited different FA profiles in intestine, brain, muscle and liver depending on diet. Following quantitative RT-PCR, steady-state levels of fabp7b transcripts were induced in brain by a diet rich in linolate; fabp1b.1and fabp7b transcripts in intestine were elevated by a diet rich in linolenate; fabp7ba transcripts in liver were elevated in fish fed a low lipid diet; and fabp7 and fabp11a transcripts were elevated in muscle by diets that were either enriched in linolate, or contained low lipid content. None of the sister duplicates of these fabp genes exhibited an increase in the steady-state transcript levels in tissues of fish fed one of the four diets. Moreover, the level of heterogeneous nuclear RNA for a given fabp gene correlated with the induction of the steady-state level of mRNA transcripts indicating that up-regulation of fabp transcripts occurred at the site of transcriptional initiation. The differential transcriptional induction of duplicated zebrafish fabp genes by dietary FAs provides further evidence to support the DDC model for retention of duplicated genes in the zebrafish genome by either subfunctionalization or neofunctionalization.
机译：在重复-变性-互补（DDC）模型中，功能不足和新功能化已被提议为驱动重复基因在基因组中保留的主要过程。这些过程被认为是由于复制基因的启动子中调控元件的增减而发生的。硬骨鱼中存在许多重复的基因，这是全基因组复制事件的结果，该事件早在250-400百万年前的有鳍鳍鱼谱系中发生。为了测试DDC模型，我选择确定由于亚功能化或新功能化，斑马鱼基因组中是否保留了重复的脂肪酸结合蛋白（fabp）基因。我首先通过两种方法确定了fabp1b.2和fabp11b基因的转录本的时空分布：（i）核糖核蛋白与成年斑马鱼的胚胎，幼虫和切片的原位杂交，以及（ii）逆转录，聚合酶链使用从成人组织中提取的RNA进行反应（RT-PCR）。这些初步研究的结果表明，fabp1和fabp11基因的重复拷贝的时空分布明显不同。此外，将斑马鱼fabp1和fabp11基因的重复副本与其单拷贝哺乳动物直系同源序列的时空分布进行比较表明，由于亚功能化或新功能化，斑马鱼fabp副本已保留在斑马鱼基因组中。在测试DDC模型的第二种实验方法中，通过定量RT-PCR测定了脂肪酸（FAs）对重复的斑马鱼fabp基因的转录诱导作用，而脂肪酸（FAs）是已知诱导多种哺乳动物fabp基因转录的化合物。饲喂四种FA含量不同的饮食的成年斑马鱼，根据饮食的不同，在肠，脑，肌肉和肝脏中表现出不同的FA分布。定量RT-PCR后，富含亚麻酸的饮食在大脑中诱导了fabp7b转录本的稳态水平；富含亚麻酸的饮食可提高肠道中的fabp1b.1和fabp7b转录本。低脂饮食的鱼肝脏中的fabp7ba转录本升高；富含亚麻酸或脂肪含量低的饮食可增加fabp7和fabp11a转录本在肌肉中的含量。这些fabp基因的姐妹重复序列中没有一个在饲喂四种饮食之一的鱼的组织中表现出稳态转录水平的增加。此外，给定fabp基因的异质核RNA水平与诱导mRNA转录的稳态水平相关，表明fabp转录本的上调发生在转录起始位点。膳食FA对重复的斑马鱼fabp基因的差异转录诱导提供了进一步的证据，以支持DDC模型通过亚功能化或新功能化将重复的基因保留在斑马鱼基因组中。

著录项

  • 作者

    Karanth, Santhosh.;

  • 作者单位

    Dalhousie University (Canada).;

  • 授予单位 Dalhousie University (Canada).;
  • 学科 Biology Molecular.;Biology Genetics.
  • 学位 Ph.D.
  • 年度 2010
  • 页码 131 p.
  • 总页数 131
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 非洲史;
  • 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