新型冠状病毒侵染所需宿主基因TMPRSS2、CTSL、PIKFYVE、TPCN2重要功能变异分析

目的研究新型冠状病毒(SARS-CoV-2)侵染所需宿主基因TMPRSS2、CTSL、PIKFYVE、TPCN2的重要功能变异在全世界不同人群间的分布差异。方法使用GTEx数据库,在新型冠状病毒的主要侵染器官肺中分析TMPRSS2、CTSL、PIKFYVE、TPCN2基因的eQTL位点。使用1 k GP(千人基因组计划)数据库,系统分析上述4个基因的错义变异在世界不同人群间的分布差异,并使用PolyPhen-2和SIFT软件预测错义突变导致的氨基酸替代是否影响蛋白功能。结果在肺中发现了4个q值小于0.05的eQTL位点,分别为TMPRSS2基因的rs35074065、CTSL基因的rs2378757、PIKFYVE基因的rs12475932、TPCN2基因的rs930786。TMPRSS2、CTSL、PIKFYVE、TPCN2基因的4个eQTL位点可能与上述4个基因在东亚人群中的较低表达水平有关。在TMPRSS2、CTSL、PIKFYVE、TPCN2基因上分别有10、6、15、30个有害错义变异,大部分变异都是低频变异,其中大多数仅在一个人群中具有特异性。唯一的例外是TPCN2基因的变异位点rs78034812,它在全球的等位基因频率大于1%,在东亚人群中具有最高的等位基因频率且该位点在物种间具有保守性。结论TMPRSS2、CTSL、PIKFYVE、TPCN2基因存在重要功能变异,这些变异的等位基因频率在不同人群间存在差异,可能影响基因的表达和功能,从而影响人群对新型冠状病毒的易感性以及感染后症状的差异。

Deficiency of two-pore segment channel 2 contributes to systemic lupus erythematosus via regulation of apoptosis and cell cycle

Background:Systemic lupus erythematosus(SLE)is a complex autoimmune disease,and the mechanism of SLE is yet to be fully elucidated.The aim of this study was to explore the role of two-pore segment channel 2(TPCN2)in SLE pathogenesis.Methods:Quantitative reverse transcription polymerase chain reaction(qRT-PCR)was used to detect the expression ofTPCN2 in SLE.We performed a loss-of-function assay by lentiviral construct in Jurkat and THP-1 cell.Knockdown ofTPCN2 were confirmed at the RNA level by qRT-PCR and protein level by Western blotting.Cell Count Kit-8 and flow cytometry were used to analyze the cell proliferation,apoptosis,and cell cycle ofTPCN2-deficient cells.In addition,gene expression profile ofTPCN2-deficient cells was analyzed by RNA sequencing(RNA-seq).Results:TPCN2 knockdown with short hairpin RNA(shRNA)-mediated lentiviruses inhibited cell proliferation,and induced apoptosis and cell-cycle arrest of G2/M phase in both Jurkat and THP-1 cells.We analyzed the transcriptome of knockdown-TPCN2-Jurkat cells,and screened the differential genes,which were enriched for the G2/M checkpoint,complement,and interleukin-6-Janus kinase-signal transducer and activator of transcription pathways,as well as changes in levels of forkhead box O,phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin,and T cell receptor pathways;moreover,TPCN2 significantly influenced cellular processes and biological regulation.Conclusion:TPCN2 might be a potential protective factor against SLE.