Conserved MIP receptor-ligand pair regulates Platynereis larval settlement
Conserved MIP receptor-ligand pair regulates Platynereis larval settlement
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DOI：
10.1073/pnas.1220285110
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发表时间：
2013-05-14
影响因子：
11.1
通讯作者：
Jekely, Gaspar
中科院分区：
文献类型：
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作者：
Conzelmann, Markus;Williams, Elizabeth A.;Jekely, Gaspar
连接后生动物幼虫和幼体阶段的生命周期转变是由神经内分泌信号（包括神经肽和激素）精心策划的。在海洋无脊椎动物的生命周期中，通常由浮游幼虫和底栖成虫阶段组成，自由游动的幼虫响应环境信号而定居到海底是关键的生命周期转变。沉降是由专门的感觉神经分泌系统（幼虫顶端器官）调节的。顶端器官在定居过程中将环境线索转化为行为反应的神经内分泌机制尚不清楚。在这里，我们展示了肌抑制肽（MIP）/尿抑素-B，一种在原口动物中广泛存在的多效神经肽，调节海洋环节动物 Platynereis dumerilii 的幼虫定居。 MIP 在环节动物幼虫顶端器官的化学感应神经分泌细胞中表达，并向其受体（果蝇性肽受体的直系同源物）发出信号，在邻近的顶端器官细胞中表达。我们通过吗啉代介导的敲低证明，MIP 通过该受体发出信号以触发沉降。这些结果揭示了保守的 MIP 受体-配体对在调节海洋环节动物沉降中的作用。
Life-cycle transitions connecting larval and juvenile stages in metazoans are orchestrated by neuroendocrine signals including neuropeptides and hormones. In marine invertebrate life cycles, which often consist of planktonic larval and benthic adult stages, settlement of the free-swimming larva to the sea floor in response to environmental cues is a key life cycle transition. Settlement is regulated by a specialized sensory-neurosecretory system, the larval apical organ. The neuroendocrine mechanisms through which the apical organ transduces environmental cues into behavioral responses during settlement are not yet understood. Here we show that myoinhibitory peptide (MIP)/allatostatin-B, a pleiotropic neuropeptide widespread among protostomes, regulates larval settlement in the marine annelid Platynereis dumerilii. MIP is expressed in chemosensory-neurosecretory cells in the annelid larval apical organ and signals to its receptor, an orthologue of the Drosophila sex peptide receptor, expressed in neighboring apical organ cells. We demonstrate by morpholino-mediated knockdown that MIP signals via this receptor to trigger settlement. These results reveal a role for a conserved MIP receptor-ligand pair in regulating marine annelid settlement.