中文摘要：

研究一个已鉴定的富亮氨酸重复结构（LRR）蛋白家族成员LRRC19,确定其组织分布及在肾组织中的表达和定位,并对其功能进行初步研究.通过RT-PCR技术检测LRRC19 mRNA在小鼠各组织中的分布;利用特异性探针mRNA杂交技术对该基因在肾组织中的表达进行精确定位;免疫荧光实验分析该蛋白的亚细胞定位;通过分泌型碱性磷酸酶（Secreted Alkaline Phosphatase SEAP）检测技术,观察转染LRRC19后细胞中转录因子核因子（NuclearFactor NF）-κB和激活蛋白（Activator Protein AP）-1的活性改变,并探讨肿瘤坏死因子（Tumor Necrosis Factor TNF）α识别LRRC19对NF-κB信号通路的影响.RT-PCR和mRNA原位杂交实验结果显示,LRRC19 mRNA主要在肾组织中表达,并集中于肾小管上皮细胞,在脾和小肠组织中亦有表达;免疫荧光结果显示,FITC标记的LRRC19-V5融合蛋白位于细胞膜上,确定其为跨膜蛋白;LRRC19在细胞内异位表达可以不同程度的增强NF-κB和AP-1的活性,TNFα和IL-1β刺激后,NF-κB活性明显升高,TNFa刺激后表现尤为显著.作为存在于肾小管上皮细胞中的跨膜受体LRRC19,可通过识别病原体分子和致炎细胞因子,介导信号传导,启动相关细胞因子转录,调节肾组织的免疫防御作用.

英文摘要：

To investigate and identify a identified member of leucine-rich repeat（LRR） protein superfamily deeply,definite its distribution in tissues and localization in kidney,and analysis the primary function of LRRC19.We examined the distribution of LRRC19 mRNA in tissues and localization in human and mouse kidney by using reverse transcriptase polymerase chain reaction（RT-PCR） and mRNA in situ hybridization.Immunofluorescence was used to identify the subcellular localization of LRRC-V5 fusion protein.Additionally,the secreted alkaline phosphatase（SEAP） activity detection was used to detect the activation of nuclear factor （NF）-κB and activator protein（AP）-1 in culture medium of HEK293T cells co-transfected pcDNA3.1-V5-LRRC19 together with pSEAP-NF-κB or pSEAP-AP-1,and the NF-κB activation of the cells co-transfected pcDNA3.1-V5-LRRC19 together with pSEAP-NF-icB induced by tumor necrosis factor（TNF）αor interleukin（IL）-1β.LRRC19 mRNA was predominantly expressed at renal proximal tubular epithelial（RTEpi） cells in kidney.Spleen and intestine also expressed in lower level as measured by RT-PCR and in situ hybridization.The green fluorescence emerged on LRRC19-V5 fusion protein labeled by FITC was located at cell membrane, so it follows that LRRC19 was a transmembrane protein could be ascertained.Furthermore, the activation of NF-κB and AP-1 in cells co-transfected LRRC19 together with the reporter plasmid was increased.TNFαrecognized by LRRC19 could boost the activation of NF-κB strongly.Our data demonstrated for the first time that LRRC19 expressed at RTEpi cells in kidney can be recognized by pathogens and proinflammatory cytokine,transmit the signal and activate transcription factor,and mediate the immunologic defence function.