主要穹窿蛋白（MVP）是穹窿复合物的主要成分，它是大多数真核生物中发现的高度保守的核糖核蛋白复合物。此前已发现 MVP 或穹窿在多重耐药癌细胞中过度表达，并参与多种细胞过程，例如细胞信号传导和先天免疫。然而，人们对 MVP 的精确功能知之甚少，并且其在低等真核生物中的表达和可能的功能也没有得到很好的表征。在这项研究中，我们报告大西洋鲑鱼虱表达三个全长 MVP 旁系同源物 (LsMVP1-3)。此外，我们扩大了搜索范围，并在其他几种蜕皮动物物种中鉴定了 MVP 直系同源物。 LsMVP 在各种组织中均在转录物和蛋白质水平上表达。此外，通过差速离心证明了 LsMVP 组装成穹窿的证据。 LsMVP被发现在水泥中高度表达，水泥是成年雌性鲑鱼虱体内一对水泥腺产生的细胞外物质。水泥对于卵串的形成很重要，卵串充当发育中胚胎的保护层。我们的结果表明 LsMVP 作为分泌性水泥蛋白可能具有新功能。 LsMVP 可能在结构或生殖功能中发挥作用，尽管这还需要进一步研究。© 2024。作者。

Major vault protein (MVP) is the main component of the vault complex, which is a highly conserved ribonucleoprotein complex found in most eukaryotic organisms. MVP or vaults have previously been found to be overexpressed in multidrug-resistant cancer cells and implicated in various cellular processes such as cell signaling and innate immunity. The precise function of MVP is, however, poorly understood and its expression and probable function in lower eukaryotes are not well characterized. In this study, we report that the Atlantic salmon louse expresses three full-length MVP paralogues (LsMVP1-3). Furthermore, we extended our search and identified MVP orthologues in several other ecdysozoan species. LsMVPs were shown to be expressed in various tissues at both transcript and protein levels. In addition, evidence for LsMVP to assemble into vaults was demonstrated by performing differential centrifugation. LsMVP was found to be highly expressed in cement, an extracellular material produced by a pair of cement glands in the adult female salmon louse. Cement is important for the formation of egg strings that serve as protective coats for developing embryos. Our results imply a possible novel function of LsMVP as a secretory cement protein. LsMVP may play a role in structural or reproductive functions, although this has to be further investigated.© 2024. The Author(s).