Abstract

Tunicata is an interesting phylogenetic group, at the base of the branch leading to Chordata. Ascidians (Tunicata, Ascidiacea) morula blood cells are involved in defense reactions and in the formation of the tunic extracellular matrix. The ascidian tunic is hardened as a result of sclerotization of matrix proteins due to the action of phenol oxidase enzyme, contained in morula cells. Morula cells of the ascidian Styela rustica contain two major proteins, the function of which is still unknown; one of them is a protein with molecular mass of 48 kDa – p48. The aim of present study was to search for possible homologues of p48 in ascidians belonging to the Stolidobranchia order: Styela coriacea (Styelidae), Molgula citrina (Molgulidae), Boltenia echinata, Halocynthia aurantium (Pyuridae) and to determine the tissue distribution of those homologues. In order to show the presence of p48 in the tissues of sea squirts we used indirect immunolabeling method on paraffin sections.It was shown that the antibodies bind with morula cells of Styela rustica, Styela coreacea, Boltenia echinata, with the tunic matrix in all studied species and with test cells of Styela rustica, Styela coreacea, Boltenia echinata, Molgula citrina. It gives us a ground to assume the existence of p48 homologues in all studied ascidians and to expect a common mechanism of their participation in the tunic formation, as possible substrates of the phenol oxidase system.

中文翻译：

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虎杖其他物种中海rusticStyela Rusta桑ula细胞中p48蛋白的同源物

摘要

Tunicata是一个有趣的系统发育群，位于通向Chordata的分支的底部。海鞘（Tunicata，Ascidiacea）桑ula的血细胞参与防御反应和外膜细胞外基质的形成。由于桑细胞中所含的酚氧化酶的作用，基质蛋白的硬化作用使海鞘外套硬化。海生Styela Rusta的桑ula细胞含有两种主要蛋白质，其功能尚不清楚。其中之一是分子量为48 kDa – p48的蛋白质。本研究的目的是在属于腕突支纲的海生动物中搜索p48的同源物：Styela coriacea（Styelidae），Molgula citrina（Molgulidae），紫锥花（Boltenia echinata），金丝雀（Halocynthia aurantium）（Pyuridae）并确定那些同源物的组织分布。为了显示海鞘组织中p48的存在，我们在石蜡切片上使用了间接免疫标记方法。研究结果表明，这些抗体均与土气的Styela，Styela coreacea，Boltenia echinata的桑ula属细胞以及中药基质结合。锈Styela，Styela coreacea，Boltenia echinata，Molgula citrina的种和测试细胞。它为我们假设所有研究的海鞘中都存在p48同源物奠定了基础，并期待它们参与中山药形成的共同机制，也可能是酚氧化酶系统的底物。