Department of Molecular Biomedical Sciences and Center for Comparative Medicine and Translational Research, North Carolina State University, 1060 William Moore Drive, Raleigh, NC, 27607, USA.
Immunogenetics. 2014 Apr;66(4):267-79. doi: 10.1007/s00251-014-0759-4. Epub 2014 Jan 28.
The polymeric immunoglobulin (Ig) receptor (pIgR) is an integral transmembrane glycoprotein that plays an important role in the mammalian immune response by transporting soluble polymeric Igs across mucosal epithelial cells. Single pIgR genes, which are expressed in lymphoid organs including mucosal tissues, have been identified in several teleost species. A single pigr gene has been identified on zebrafish chromosome 2 along with a large multigene family consisting of 29 pigr-like (PIGRL) genes. Full-length transcripts from ten different PIGRL genes that encode secreted and putative inhibitory membrane-bound receptors have been characterized. Although PIGRL and pigr transcripts are detected in immune tissues, only PIGRL transcripts can be detected in lymphoid and myeloid cells. In contrast to pIgR which binds Igs, certain PIGRL proteins bind phospholipids. PIGRL transcript levels are increased after infection with Streptococcus iniae, suggesting a role for PIGRL genes during bacterial challenge. Transcript levels of PIGRL genes are decreased after infection with Snakehead rhabdovirus, suggesting that viral infection may suppress PIGRL function.
多聚免疫球蛋白受体（pIgR）是一种完整的跨膜糖蛋白，通过将可溶性多聚免疫球蛋白转运穿过黏膜上皮细胞，在哺乳动物免疫反应中发挥重要作用。已在包括黏膜组织在内的淋巴器官中鉴定出几种鱼类的单一 pIgR 基因。在斑马鱼的 2 号染色体上鉴定出了一个单一的 pigr 基因，以及一个由 29 个 pigr 样（PIGRL）基因组成的大型多基因家族。已经对编码分泌型和假定抑制性膜结合受体的十个不同 PIGRL 基因的全长转录本进行了特征描述。尽管 PIGRL 和 pigr 转录本在免疫组织中均有检测到，但仅在淋巴样和髓样细胞中可检测到 PIGRL 转录本。与结合 Ig 的 pIgR 不同，某些 PIGRL 蛋白结合磷脂。在感染鳗弧菌后，PIGRL 转录本水平增加，表明 PIGRL 基因在细菌挑战期间发挥作用。感染蛇头鱼虹彩病毒后 PIGRL 基因的转录本水平降低，表明病毒感染可能抑制 PIGRL 功能。
