FRE3484 BioMEA, Université de Caen Basse-Normandie, F-14032 Caen, France.
Peptides. 2013 Aug;46:159-66. doi: 10.1016/j.peptides.2013.05.004. Epub 2013 Jun 11.
Two novel members of the oxytocin/vasopressin superfamily have been identified in the cephalopod Sepia officinalis. Oxytocin/vasopressin gene sequences were cloned by Race PCR. The two precursors we identified exhibit the classical organization of OT/VP superfamily precursors: a signal peptide followed by a nonapeptide and a neurophysin domain. The neurophysin domain is entirely conserved for the cuttlefish precursors, but the nonapeptides and the signal peptides differ. The first nonapeptide, called sepiatocin, is highly homologous to Octopus vulgaris octopressin. The second nonapeptide, called pro-sepiatocin, shows sequence homologies with a Crustacean oxytocin/vasopressin-like peptide identified in Daphnia culex and with a novel form of oxytocin described in New World monkeys. The expression of pro-sepiatocin is restricted to the supraesophageal and subesophageal masses of the brain whereas sepiatocin is expressed in the entire central nervous system. Sepiatocin, as described for octopressin, modulates the contractile activity of several muscles such as penis, oviduct and vena cava muscles; this suggests its involvement in reproduction and blood circulation. Pro-sepiatocin is released in the hemolymph; it is a neurohormone able to target numerous peripheral organs.
已在头足纲动物乌贼中鉴定出两种新的催产素/加压素超家族成员。通过 Race PCR 克隆了催产素/加压素基因序列。我们鉴定的两个前体表现出 OT/VP 超家族前体的经典组织：信号肽后接九肽和神经垂体域。神经垂体域对于乌贼前体是完全保守的，但九肽和信号肽不同。第一种九肽，称为章鱼催产素，与章鱼 octopressin 高度同源。第二种九肽，称为前章鱼催产素，与在 Daphnia culex 中鉴定的甲壳类动物催产素/加压素样肽以及在新世界猴子中描述的一种新形式的催产素具有序列同源性。前章鱼催产素的表达仅限于脑的上食管和下食管块，而章鱼催产素则在整个中枢神经系统中表达。如章鱼加压素所述，章鱼催产素调节阴茎、输卵管和腔静脉等几种肌肉的收缩活动；这表明它参与了生殖和血液循环。前章鱼催产素在血淋巴中释放；它是一种能够靶向许多外周器官的神经激素。
