DISSERTATION RESEARCH: The evolutionary recruitment of effector genes into a novel sensory system

果蝇（Drosophila prolongata）在前腿上有一套独特的感觉器官。这项研究检查了它们细胞的基因组学，以了解一组基因是如何被招募形成一种新的特化细胞类型的。不同类型的组织和细胞是由基因的表达来区分的。细胞通过开启这些功能所需的基因，同时关闭其他基因，来产生不同的功能。基因表达错误是发育障碍和其他疾病的原因之一，但其表达控制机制仍未得到很好的理解。观察招募过程的模式将说明一种新的细胞类型是如何进化的，基因表达是如何在不同类型的细胞和组织中被控制的，以及为什么表达控制被打破。这项研究将扩大研究生的培养，他们还将领导大学的公共宣传活动，并为高中生和本科生提供研究经验。为了研究基因募集过程，我们将推断果蝇新感觉器官中基因表达的进化史。我们将对其前腿和几个近亲物种的mRNA进行测序。mRNA中存在的基因序列反映了哪些基因被表达。这些将根据与已知感觉基因序列的相似性进行过滤；那些只存在于龙葵样本中的基因代表了获得了新的组织特异性的基因。这些基因将与其他蝇类的相关基因进行比较，包括已经得到充分研究的黑腹蝇，以确定哪些特征使基因更容易受到表达变化的影响。进化模式反映了自然发生的变异，并提示了在其他生物体中产生表达控制的机制，以及与基因调控相关的因素。

The fruit fly Drosophila prolongata exhibits a unique set of sensory organs on the front legs. This study examines the genomics of their cells to learn how a group of genes is recruited to form a new specialized cell type. Distinct types of tissues and cells are differentiated by which genes are expressed. Cells produce their varied functions by turning the genes necessary for these roles on, while keeping other genes off. Errors in the expression of genes is one cause of developmental disorders and other diseases, yet the mechanisms of expression control are still not well understood. Observing the patterns of the recruitment process will illustrate how a new cell type evolves, how gene expression is controlled in different types of cells and tissue, and why expression control breaks down. This research will expand the training of a graduate student, who also leads public outreach activities at his university and provides research experiences for high school students and undergraduates. To study the gene recruitment process, the evolutionary history of genes expressed in the novel sensory organs of Drosophila prolongata will be inferred. The mRNA from forelegs of this and several closely related species will be sequenced. The gene sequences present in the mRNA reflect which genes are expressed. These will be filtered based on similarity to sequences of known sensory genes; those present only in D. prolongata samples represent genes that have acquired new tissue specificity. These genes will be compared to related genes in other fly species, including the well-studied D. melanogaster, to determine what characteristics make genes more malleable to expression shifts. The evolutionary patterns reflect naturally occurring variation and suggest mechanisms of creating expression control, factors relevant to gene regulation in other organisms.