School of Biological Sciences, University of Bristol Bristol, UK.
Front Physiol. 2013 May 30;4:117. doi: 10.3389/fphys.2013.00117. eCollection 2013.
Great advances have been made recently in understanding the genetic basis of the sensory biology of bats. Research has focused on the molecular evolution of candidate sensory genes, genes with known functions [e.g., olfactory receptor (OR) genes] and genes identified from mutations associated with sensory deficits (e.g., blindness and deafness). For example, the FoxP2 gene, underpinning vocal behavior and sensorimotor coordination, has undergone diversification in bats, while several genes associated with audition show parallel amino acid substitutions in unrelated lineages of echolocating bats and, in some cases, in echolocating dolphins, representing a classic case of convergent molecular evolution. Vision genes encoding the photopigments rhodopsin and the long-wave sensitive opsin are functional in bats, while that encoding the short-wave sensitive opsin has lost functionality in rhinolophoid bats using high-duty cycle laryngeal echolocation, suggesting a sensory trade-off between investment in vision and echolocation. In terms of olfaction, bats appear to have a distinctive OR repertoire compared with other mammals, and a gene involved in signal transduction in the vomeronasal system has become non-functional in most bat species. Bitter taste receptors appear to have undergone a "birth-and death" evolution involving extensive gene duplication and loss, unlike genes coding for sweet and umami tastes that show conservation across most lineages but loss in vampire bats. Common vampire bats have also undergone adaptations for thermoperception, via alternative splicing resulting in the evolution of a novel heat-sensitive channel. The future for understanding the molecular basis of sensory biology is promising, with great potential for comparative genomic analyses, studies on gene regulation and expression, exploration of the role of alternative splicing in the generation of proteomic diversity, and linking genetic mechanisms to behavioral consequences.
最近，人们在理解蝙蝠感觉生物学的遗传基础方面取得了重大进展。研究集中在候选感觉基因的分子进化上，这些候选基因包括具有已知功能的基因（例如嗅觉受体 (OR) 基因）和从与感觉缺陷相关的突变中鉴定出的基因（例如失明和失聪）。例如，FoxP2 基因是发声行为和感觉运动协调的基础，在蝙蝠中发生了多样化，而与听觉相关的几个基因在回声定位蝙蝠的无关谱系中表现出平行的氨基酸取代，在某些情况下，在回声定位海豚中也表现出平行的氨基酸取代，这代表了趋同分子进化的经典案例。编码视黄醛和长波敏感视蛋白的视觉基因在蝙蝠中具有功能，而编码短波敏感视蛋白的基因在使用高占空比喉声回声定位的皱唇蝠中失去了功能，这表明在视觉和回声定位之间存在感觉权衡。就嗅觉而言，与其他哺乳动物相比，蝙蝠似乎具有独特的 OR 库，而参与鼻甲骨系统信号转导的基因在大多数蝙蝠物种中已失去功能。苦味受体似乎经历了涉及广泛基因复制和丢失的“生与死”进化，与编码甜味和鲜味的基因不同，这些基因在大多数谱系中都保持保守，但在吸血蝙蝠中丢失。普通吸血蝙蝠还通过选择性剪接产生了一种新型热敏通道，从而适应了热感觉。通过比较基因组分析、基因调控和表达研究、探索选择性剪接在蛋白质组多样性产生中的作用、将遗传机制与行为后果联系起来等方面，理解感觉生物学的分子基础具有广阔的前景。
