Developmental Buffering in a Gene Regulatory Network

在生命系统中，基因表达中的噪音会导致表型的差异，即使是在基因相同的细胞之间也是如此。这个项目将以线虫肠道发育为模型，研究携带相同基因的动物出现不同表型的基础。控制肠道规范的遗传途径涉及基因END-1和END-3的瞬时激活。这些基因的突变版本已经被引入到缺乏正常拷贝的线虫动物中。初步结果显示，只有一些胚胎会产生肠道，而存活下来的成年人的肠道是不正常的。本项目将研究这些影响的基础。首先，将以高分辨率检查末端突变胚胎的肠道发育。第二，将成人肠道的整体基因表达与正常动物进行比较，并测试肠道指定途径中可能存在的基因功能缺陷。第三，将测量肠道规格最上游成分的噪声源，并识别其产物影响肠道随机规格的基因。将使用反向遗传学(使用RNA干扰)、时间推移显微镜和高通量表达基因测序(RNA-Seq)。这些实验将在一组新的突变体中以高分辨率描述肠道发育，表征突变菌株在成年肠道中的缺陷，并在器官规格中识别可能的基因表达噪音来源。这项工作有可能为生命系统如何管理发育过程中基因表达的内在差异定义新的范式。在执行这项工作的过程中，西班牙裔PI本人将培训来自多元化的加州大学河滨分校的本科生和一名研究生。为生物学一年级本科生开设的实验室课程将训练学生进行研究，并允许他们进行原创性研究。

In living systems, noise in gene expression can lead to differences in phenotype, even among genetically identical cells. This project will study the basis for different phenotypes occurring in animals carrying the same genotype, using the development of the gut in the nematode C. elegans as a model. The genetic pathway controlling specification of the gut involves transient activation of the genes end-1 and end-3. Mutated versions of these genes have been introduced into C. elegans animals that lack the normal copies. Preliminary results show that only some embryos make gut, and that surviving adults have abnormal guts. This project will study the basis for these effects. First, the development of the gut in end mutant embryos will be examined at high resolution. Second, global gene expression in adult guts will be compared with normal animals, and possible defects in function of genes in the gut specification pathway will be tested. Third, sources of noise in the upstream-most components of gut specification will be measured, and genes whose products influence the stochastic specification of gut will be identified. Reverse genetics (using RNA interference), time lapse microscopy, and high-throughput sequencing of expressed genes (RNA-Seq) will be used. The experiments will describe gut development at high resolution in a new set of mutants, characterize defects in adult intestines derived from the mutant strains, and identify possible sources of gene expression noise in organ specification. The work has the potential to define new paradigms for how living systems manage inherent differences in gene expression during development. In the course of performing this work, the PI, himself of Hispanic descent, will train undergraduates from the diverse UC Riverside campus, and a graduate student. A laboratory course for first-year Biology undergraduates will train students in research and allow them to carry out original research.