Lane Robert P, Young Janet, Newman Tera, Trask Barbara J
Department of Molecular Biology and Biochemistry, Wesleyan University, Middletown, Connecticut 06459, USA.
Genome Res. 2004 Apr;14(4):603-8. doi: 10.1101/gr.2117004.
The mouse V1R putative pheromone receptor gene family consists of at least 137 intact genes clustered at multiple chromosomal locations in the genome. Species-specific pheromone receptor repertoires may partly explain species-specific social behavior. We conducted a genomic analysis of an orthologous pair of mouse and rat V1R gene clusters to test for species specificity in rodent pheromone systems. Mouse and rat have lineage-specific V1R repertoires in each of three major subfamilies at these loci as a result of postspeciation duplications, gene loss, and gene conversions. The onset of this diversification roughly coincides with a wave of Line1 (L1) retrotranspositions into the two loci. We propose that L1 activity has facilitated postspeciation V1R duplications and gene conversions. In addition, we find extensive homology among putative V1R promoter regions in both species. We propose a regulatory model in which promoter homogenization could ensure that V1R genes are equally competitive for a limiting transcriptional structure to account for mutually exclusive V1R expression in vomeronasal neurons.
小鼠V1R假定信息素受体基因家族由至少137个完整基因组成，这些基因聚集在基因组中的多个染色体位置。物种特异性的信息素受体库可能部分解释了物种特异性的社会行为。我们对小鼠和大鼠V1R基因簇的直系同源对进行了基因组分析，以测试啮齿动物信息素系统中的物种特异性。由于物种形成后的重复、基因丢失和基因转换，小鼠和大鼠在这些位点的三个主要亚家族中的每一个都有谱系特异性的V1R库。这种多样化的开始大致与一波Line1（L1）逆转录转座进入这两个位点的时间相吻合。我们提出L1活性促进了物种形成后的V1R重复和基因转换。此外，我们在两个物种的假定V1R启动子区域中发现了广泛的同源性。我们提出了一种调控模型，其中启动子同质化可以确保V1R基因在有限的转录结构中具有同等竞争力，以解释犁鼻神经元中V1R表达的相互排斥性。
