猪PILRA基因克隆及变异剪接体鉴定

Cloning and identification of splice variants of the porcine PILRA gene

Ⅱ型成对免疫球蛋白样受体（Paired immunoglobulin-like type 2 receptors,PILRs）是免疫球蛋白超家族成员之一,包括α和β两个亚型。PILRα在机体抵抗病原体入侵的免疫反应中发挥着重要作用,但目前尚未见关于猪PILRα的报道。为了分析其在猪抗病育种中的作用,本文克隆了猪PILRα编码基因（PILRA）并鉴定变异剪接体,利用实时荧光定量PCR方法构建其组织表达谱和诱导表达谱。结果表明,成功克隆了猪PILRA基因的3个变异剪接体V1~V3（Gen Bank登录号：KJ143679~81）,预测的蛋白质多肽链分别长271 aa、254 aa和283 aa,且都具有免疫球蛋白结构域。各变异剪接体均在脾脏中表达量最高,肝脏、肺脏次之,在心脏、肾脏、胃、肌肉、淋巴、大肠、小肠和膀胱等组织中表达量较低或检测不到。Poly（I：C）能显著诱导变异剪接体V1的表达,但几乎不影响V2、V3的表达。研究结果为进一步揭示PILRA在猪抗病育种中的作用提供了基础。

Paired immunoglobulin-like type 2 receptors （PILRs） are members of the immunoglobulin superfamily and composed of two subtypes, α and β. PILRα plays an important role in the immune response against invading pa- thogens, but so far there is no report on porcine PILRα. In order to analyze the potential role of PILRα in porcine disease-resistant breeding, we first cloned the PILRA gene （V1-V3, GenBank accession Nos. KJ143679-81） into pigs, and identified its three splice variants. Each variant conceptually translates into proteins of 271 amino acids （aa）, 254aa and 283aa, respectively. Furthermore, quantitative real-time PCR was used to construct expression profiles of each variant in tissues and that induced by Poly（hC）. All three variants had the highest expression levels in the spleen, followed by liver and lung tissues. While levels were low or undetectable in the heart, kidney, stomach, muscle,lymph, large intestine, small intestine and bladder. Poly（I：C） significantly induced the expression of splice variant 1 （V1） of porcine PILRA, but hardly affected the expression of V2 and V3. The results lay a foundation for further study on the role of PILRA in porcine breeding and disease resistance.