Pathogenomics of collagen disease using synthetic polymorphic proteins and BAG transgenic mice

涉及SLE和RA的胶原蛋白疾病表现出复杂的病理表现，如肾小球肾炎、血管炎、关节炎和/或涎腺炎，这似乎是多个基因位点以等位基因组合累积作用的结果。在本研究中，我们着重于在MRL模型小鼠中鉴定这些基因。携带Fas缺失突变基因lprr （MRL/lpr）的MRL/MpJ-lpr/lpr小鼠，在同一个体中自发发展各种形式的胶原蛋白疾病，包括肾小球肾炎、多动脉炎、关节炎和涎腺炎，与MRL背景相关。此前，我们利用C3H/lpr小鼠与N2回交和F2交鼠进行多态微卫星标记，定位了每个病变的易感位点，并阐明了每个病变的基因位点存在于不同的染色体位置，它们具有多基因的加性和层次性。为了确定每个位点的候选基因，我们采用了新的策略。1)体外合成候选基因对应的多态性蛋白功能分析；2)MRL/lpr与C3H/lpr小鼠间的重组近交系培养及菌株分布模式表，并进行病原学研究；3)培养具有候选位置位点对应的BAG（细菌人工染色体）的转基因小鼠，进行病理分析。我们认为，这些研究能够有效地阐明基于功能基因组学的涉及胶原蛋白疾病的多基因疾病的易感基因。

Collagen disease involving SLE and RA shows a complex pathological manifestation such as glomerulonephritis, vasculitis, arthritis and/or sialoadenitis, which seems to result from the cumulative effect of multiple gene loci with an allelic combination. In this research, we focused on to identify these genes in MRL model mice.MRL/MpJ-lpr/lpr mice bearing a Fas deletion mutant gene lprr (MRL/lpr), spontaneously develop various forms of collagen disease in the same individuals, including glomerulonephritis, polyarteritis, arthritis and sialoadenitis, associated with an MRL background. Previously, we mapped susceptibility loci to each lesion with polymorphic microsatellite markers using N2 backcross and F2 intercross mice with C3H/lpr mice, and clarified that gene loci responsible for each lesion exist at different chromosomal positions and they have additive and hierarchical properties in a polygenic manner. To identify the candidate genes for each locus, we performed novel strategies. 1) functional analyses of synthetic polymorphic proteins corresponding to the candidate genes in vitro, 2) development of recombinant inbred strains of mice between MRL/lpr and C3H/lpr mice and the strain distribution pattern table, followed by the pathogenimics studies, 3) development of transgenic mice with BAG (bacterial artificial chromosomes) corresponding to the positional candidate loci, followed by the pathological analyses.We conclude that these studies were efficient to clarify the susceptibility genes to polygenic diseases involving collagen disease based on functional genomics.