Environmental Science Programs and Division of Life Science, School of Science, the Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong S.A.R., P. R. China.
Sanya Institute of Deep-sea Science and Engineering, Chinese Academy of Science, No. 62, Fenghuang Road, Sanya, Hainan, 572000, P. R. China.
Sci Rep. 2016 Jul 20;6:29376. doi: 10.1038/srep29376.
Settlement-inducing protein complex (SIPC) is a pheromone that triggers conspecific larval settlement in the barnacle Amphibalanus amphitrite. In the present study, immunostaining and scanning electron microscopy of SIPC revealed signals in the frontal horn pores and the secretions from carapace pores, suggesting that SIPC might be directly secreted from these organs in A. amphitrite cyprids. Further observations showed that the frontal horn pores could contact surfaces while cyprids were "walking". Immunostaining for SIPC on the contacted surfaces displayed SIPC signals. These signals were similar to the frontal horn pores in size and morphology, suggesting that frontal horn pores might deposit SIPC. Besides, full-length SIPC was expressed and subsequent assays indicated that recombinant SIPC was able to bind to chitins and induce the precipitation of CaCO3. Furthermore, recombinant SIPC inhibited the formation of vaterites and regulated the morphology of calcite crystals. The crystals that formed with recombinant SIPC were more stable against water erosion. Overall, these results reported a novel function of recombinant SIPC that regulates crystal formation in barnacle shells.
定居诱导蛋白复合物（SIPC）是一种信息素，可触发藤壶 Amphibalanus amphitrite 同种幼虫的定居。在本研究中，通过 SIPC 的免疫染色和扫描电子显微镜观察，在前额角孔和甲壳孔分泌物中发现了信号，表明 SIPC 可能直接从 A. amphitrite 幼体的这些器官中分泌出来。进一步的观察表明，在前额角孔可以接触到表面，而幼体在“行走”时。在接触表面上对 SIPC 进行免疫染色显示出 SIPC 信号。这些信号在大小和形态上与前额角孔相似，表明前额角孔可能沉积了 SIPC。此外，全长 SIPC 被表达，随后的测定表明重组 SIPC 能够与几丁质结合，并诱导 CaCO3 的沉淀。此外，重组 SIPC 抑制了方解石的形成，并调节了方解石晶体的形态。形成重组 SIPC 的晶体对水侵蚀更稳定。总的来说，这些结果报道了重组 SIPC 的一个新功能，即调节藤壶壳中晶体的形成。
