The olfactory gene repertoire in salmonids

鲑鱼能够进行长途海洋旅行，并能够回到它们纳塔尔河流，这一能力长期以来一直吸引着生物学家和公众。鲑鱼在淡水中利用嗅觉返回产卵地。这种忠实的回归建立了鲑鱼的种群结构，并使它们能够适应当地的条件。我的研究项目的根本目标是了解嗅觉在决定鲑鱼如何返回其出生地方面的作用。拟议的研究利用了我通过以前的大规模鲑鱼基因组学项目帮助开发的基因组资源，最终在国际合作中对大西洋鲑鱼基因组进行测序。此外，它将建立在我的实验室在大西洋鲑鱼的嗅觉受体基因的表征最近的工作。存在四类嗅觉受体：V1Rs（奥拉斯）、V2Rs（OlfCs）、MORs和TAAR。我们组的一个实习生，K。Johnstone（PhD 2012）在大西洋鲑鱼和许多MOR中鉴定了所有ora和OlfC基因。这项拟议研究的第一个目标是完成大西洋鲑鱼嗅觉受体基因的清单。这将为研究嗅觉受体的功能及其基因如何调节提供必要的基本信息。如果嗅觉受体有助于鲑鱼归巢到不同的河流系统，那么不同的鲑鱼种群，特别是那些具有不同生活史策略的鲑鱼，应该有不同的嗅觉受体。在保持与这一假设，研究计划的第二个目标是检查所有类别的嗅觉受体在青少年，小鲑鱼和返回的成年人从两个溯河产卵和一个居民人口的大西洋鲑鱼在纽芬兰的表达模式，并寻找这些人口之间的等位基因变异。第三个目标是将研究范围扩大到红鲑和非洄游形式的科卡尼，这两种鱼在不同的生态环境中都有明确的种群。这项研究计划将导致更好地了解鲑鱼迁徙和当地适应，这将对野生鲑鱼的保护产生实际影响。

The ability of salmon to undertake long marine journeys and to navigate their way back to their natal streams has long fascinated biologists and the public alike. Salmon use olfactory cues in their freshwater migration back to the spawning grounds. This faithful return establishes the population structure of salmon, and enables them to adapt to local conditions. The underlying objective of my research program is to understand the role of olfaction in determining how salmon return to their birthplace. The proposed research takes advantage of the genomic resources that I helped develop through previous large scale salmon genomics projects culminating in the International Cooperation to Sequence the Atlantic Salmon Genome. In addition, it will build on recent work in my laboratory on the characterization of olfactory receptor genes in Atlantic salmon. There are four classes of olfactory receptors: V1Rs (oras), V2Rs (OlfCs), MORs and TAARs. A trainee in my group, K. Johnstone (PhD 2012), identified all of the ora and OlfC genes in Atlantic salmon and many of the MORs. The first goal of the proposed research is to complete the inventory of the olfactory receptor genes in Atlantic salmon. This will provide the basic information necessary to carry out research into the function of olfactory receptors and how their genes are regulated. If olfactory receptors contribute to the homing of salmon to different river systems, then different salmon populations, especially those with different life history strategies, should have different complements of olfactory receptors. In keeping with this hypothesis, the second goal of the research program is to examine the expression patterns of all classes of olfactory receptors in juveniles, smolts and returning adults from two anadromous and one resident population of Atlantic salmon in Newfoundland, and to search for allelic variation between these populations. The third goal is to expand the studies to sockeye salmon and kokanee, the non-migratory form, both of which have well-defined populations in different ecological niches. This program of research will lead to a better understanding of salmon migration and local adaptation, which will have practical implications for the conservation of wild salmon.