Characterization of SLE-Susceptability Loci on Mouse Chromosome 1

小鼠 1 号染色体上 SLE 易感性位点的表征

• 批准号: 7569453
• 负责人: Laurence Morel
• 金额: $ 42.14万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-01 至 2013-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7569453
• 关键词: Adaptor Signaling Protein; Alleles; Autoimmune Process; Autoimmunity; Bone Marrow Cells; Candidate Disease Gene; Chromosomes, Human, Pair 1; Genes; Genetic Polymorphism; Goals; Haplotypes; Homeobox; Human; Lentivirus Vector; Lupus; Maps; Modeling; Molecular; Mus; Names; Nuclear; Nuclear Antigens; Pathogenesis; Pathway interactions; Patients; Phenotype; Pre-B-Cell Leukemia; Predisposition; Protein Isoforms; RNA Splicing; Reading; Recombinants; Resistance; Risk Factors; SNP genotyping; Systemic Lupus Erythematosus; T-Lymphocyte; autoreactive T cell; congenic; duplicate genes; estrogen-related receptor; genetic analysis; in vitro Assay; in vivo; mouse model; novel; research study; transcription factor

DESCRIPTION (provided by applicant): The goal of this proposal is identify the genes that correspond to the lupus susceptibility loci Sle1a and Sle1c and to determine the molecular and functional mechanisms by which their NZW alleles contribute to autoimmunity. We have evidence from congenic recombinants that 3 genes located in the Sle1a region contribute to lupus pathogenesis, for which we have identified two strong positional candidates: Pbx1, a ubiquitous homeobox transcription factor for Sle1a-1, and Sh2d1b / Sh2d1c, two duplicated genes that encode for adaptor proteins of the SLAM molecules, for Sle1a-2. In addition, Fcgr2b has already been associated to lupus in patients and in the NZM2410 model. In parallel, we have shown that an autoreactive T cell phenotype maps to the centromeric portion of Sle1c that we named Sle1c-2 (Sle1c-1 being Cr2). The analysis of congenic recombinants has identified two positional candidates for Sle1c-2, Erssg (estrogen-related receptor 3) and Ush2a (Usherin). To characterize these candidate genes, we have three specific aims. 1: To characterize the NZW allele of candidate genes for Sle1a-1, Sle1a-2, and Sle1c-2. We will use SNP genotyping to better define the critical interval for each locus and determine the SNP haplotype distribution within and around the candidate genes. We will characterize the NZW alleles for the four candidate genes in term of sequence and expression polymorphisms, and splice isoforms distribution. 2: To determine the mechanisms by which Sle1a-1, Sle1a-2 and Sle1c-2 and Fcgr2bNZW contribute to autoimmunity. We will use the in vivo and in vitro assays that we have developed to analyze the autoimmune phenotypes of the whole Sle1a and Sle1c intervals on the Sle1a and Sle1c congenic recombinants to pinpoint the cellular compartments and dissect the molecular mechanisms by which Sle1a-1, Sle1a-2 and Sle1c-2 induce autoimmune phenotypes. In addition, we will perform experiments to further characterize how the NZW allele of Fcgr2b contributes to autoimmunity.3: To validate the contribution of candidate genes to the Sle1a-1, Sle1a-2 and Sle1c-2 phenotypes. We will use lentiviral vectors (LV) to validate the candidate genes by either restoring a normal phenotype in the Sle1a or Sle1c sub-congenics, or by inducing a Sle1a or Sle1c phenotype in B6 mice, with bone-marrow cells LV-transduced with either the resistance or susceptibility alleles. The phenotypes and cellular compartments characterized in Aim 2 will be used as read-outs for the effects of over-expression of resistance or susceptibility alleles. This combined approach will identify the molecular and cellular mechanisms by which Sle1a and Sle1c-2 contributes to lupus pathogenesis, which we predict will be novel pathways regulating T cell tolerance to nuclear antigens.This project proposes to identify 3 genes that contribute to systemic lupus erythematosus, more specifically to the loss of tolerance to nuclear antigens in a spontaneous mouse model. Genetic analyses have provided a short list of candidate genes that we propose to characterize at the molecular and functional levels. These genes represent potential risk factors for human SLE patients and/or new disrupted pathways that are involved in lupus pathogenesis.

描述（由申请人提供）：该提案的目的是确定与狼疮易感性基因座和SLE1C相对应的基因，并确定其NZW等位基因对自身免疫有助于的分子和功能机制。我们有来自友善重组因素的证据表明，位于SLE1A区域的3个基因有助于狼疮发病机理，为此我们确定了两个强的位置候选：PBX1，一种无处不在的SLE1A-1的同源性转录因子，用于SLE1A-1，SH2D1B / SH2D1B / SH2D1C，两个重复的基因供应量子slam slam slam slam slam slam slam slam slam slam slam slam slam slam slam slam slam slam-fam。此外，在患者和NZM2410模型中，FCGR2B已经与狼疮有关。同时，我们已经表明，自动反应性T细胞表型映射到我们称为SLE1C-2（SLE1C-1为CR2）的SLE1C的丝粒部分。先天重组者的分析已经确定了SLE1C-2，ERSSG（雌激素相关受体3）和USH2A（USHERIN）的两个位置候选者。为了表征这些候选基因，我们有三个特定的目标。 1：表征SLE1A-1，SLE1A-2和SLE1C-2的NZW等位基因的NZW等位基因。我们将使用SNP基因分型更好地定义每个基因座的临界间隔，并确定候选基因内部和周围的SNP单倍型分布。我们将以序列和表达多态性的术语和剪接同工型分布来表征四个候选基因的NZW等位基因。 2：确定SLE1A-1，SLE1A-2和SLE1C-2和FCGR2BNZW的机制有助于自身免疫性。我们将使用我们开发的体内和体外测定法分析SLE1A和SLE1C上的整个SLE1A和SLE1C间隔的自身免疫表型，并通过SLE1A-1，SLE1A-1，SLE1A-2，SLE1C-2 Indipute AutoimnAne Pactiptectipt sle1a和sle1c concy1 companic重组剂来查明细胞隔室并剖析分子力学。此外，我们将进行实验，以进一步表征FCGR2B的NZW等位基因如何促进自身免疫性。3：验证候选基因对SLE1A-1，SLE1A-2和SLE1C-2表型的贡献。我们将使用慢病毒载体（LV）来通过恢复SLE1A或SLE1C亚综合剂的正常表型，或通过骨髓细胞LV转移的抗药性或敏感性同elles中的B6小鼠中的SLE1A或SLE1C表型来验证候选基因。在AIM 2中表征的表型和细胞室将用作读出耐药性或易感性等位基因过表达的影响。这种组合的方法将确定SLE1A和SLE1C-2有助于狼疮发病机理的分子和细胞机制，我们预测这将是调节T细胞对核抗原的耐受性的新途径。该项目建议识别3个基因，这些基因有助于造成耐受性的全身性狼疮的效果，以替代型核蚂蚁，使核蚂蚁造成了型核蚂蚁的损失。遗传分析提供了我们建议在分子和功能水平上表征的候选基因的简短列表。这些基因代表了人类SLE患者和/或狼疮发病机理涉及的新途径的潜在危险因素。