Jaw size variation is associated with a novel craniofacial function for galanin receptor 2 in an adaptive radiation of pupfishes.
Jaw size variation is associated with a novel craniofacial function for galanin receptor 2 in an adaptive radiation of pupfishes.
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下颌尺寸的变化与甘丙肽受体 2 在河豚鱼适应性辐射中的一种新的颅面功能有关。
DOI：
10.1101/2023.06.02.543513
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Martin,ChristopherH
中科院分区：
文献类型：
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作者：
Palominos,MFernanda;Muhl,Vanessa;Richards,EmilieJ;Miller,CraigT;Martin,ChristopherH
了解具有新适应性的新物种的起源是生物学中的一个基本问题，也为发现具有潜在临床意义的新基因和调控网络提供了机会。在这里，我们展示了一个新的角色galr2在脊椎动物颅面发育中使用的非模型适应性辐射的营养专家pupfishes特有的圣萨尔瓦多岛在巴哈马群岛。我们证实了Sry转录因子结合位点的损失，在鳞片吃的pupfish，并发现显着的空间差异galr2的表达pupfish物种之间的Meckel的软骨和前颌骨使用原位杂交。然后，我们通过将胚胎暴露于Galr2，实验证实了Galr2在颅面发育和下颌伸长中的新功能。Galr2抑制减少梅克尔的软骨长度和增加软骨细胞密度营养专家，但不是在通才的遗传背景。我们提出了一种机制，下颌骨伸长的鳞片吃的基础上减少的表达galr2 puppet由于损失的Sry结合位点，导致减少的机会与他们的内源性配体结合在颅面软骨形成。较少的Galr2受体在鳞片吃梅克尔的软骨可能会导致其扩大颌骨长度作为成年人的限制机会Galr2拮抗剂结合这些受体在发展过程中。我们的研究结果表明，在非模型脊椎动物系统中，候选自适应SNPs与具有高度差异表型的新基因功能之间的联系越来越实用，对人类生物学具有潜在的影响。
Understanding the origins of new species with novel adaptations is a fundamental question in biology that also provides an opportunity to uncover new genes and regulatory networks with potential clinical relevance. Here we demonstrate a new role for galr2 in vertebrate craniofacial development using a non-model adaptive radiation of trophic specialist pupfishes endemic to San Salvador Island in the Bahamas. We confirmed the loss of a Sry transcription factor binding site in scale-eating pupfish and found significant spatial differences in galr2 expression among pupfish species in the Meckel's cartilage and premaxilla using in situ hybridization. We then experimentally confirmed a novel function for Galr2 in craniofacial development and jaw elongation by exposing embryos to Galr2. Galr2-inhibition reduced Meckel's cartilage length and increased chondrocyte density in both trophic specialists but not in the generalist genetic background. We propose a mechanism for jaw elongation in scale-eaters based on the reduced expression of galr2 putatively due to the loss of the Sry binding site that results in reduced opportunities for binding with their endogenous ligand during craniofacial chondrogenesis. Fewer Galr2 receptors in the scale-eater Meckel's cartilage may result in their enlarged jaw lengths as adults by limiting opportunities for Galr2 antagonists to bind to these receptors during development. Our findings illustrate the growing utility of linking candidate adaptive SNPs in non-model vertebrate systems with highly divergent phenotypes to novel gene functions with potential implications for human biology.