FTO-mediated m6A modification alleviates autoimmune uveitis by regulating microglia phenotypes via the GPC4/TLR4/NF-κB signaling axis  

作　　者：Siyuan He Wanqian Li Guoqing Wang Xiaotang Wang Wei Fan Zhi Zhang Na Li Shengping Hou 

机构地区：[1]The First Affiliated Hospital of Chongqing Medical University,Chongqing 400016,China [2]Chongqing Key Laboratory of Ophthalmology,Chongqing 400016,China [3]Chongqing Eye Institute,Chongqing 400016,China [4]Chongqing Branch of National Clinical Research Center for Ocular Diseases,Chongqing 400016,China [5]College of Basic Medicine,Chongqing Medical University,Chongqing 400016,China

出　　处：《Genes & Diseases》2023年第5期2179-2193,共15页基因与疾病（英文）

基　　金：supported by the National Natural Science Foundation Project of China(No.82070951,82271078 and 81873678);the Innovative Research Group Project of Chongqing Education Commission(China)(No.CXQT19015);the Natural Science Foundation Project of Chongqing,China(No.cstc2019jcyjmsxmx0120);the Innovation Supporting Plan of Overseas Study of Chongqing,China(No.cx2018010);the Chongqing Education Commission(China)(No.KJQN202000406);the National Key Clinical Specialties Construction Program of China,Chongqing Branch of National Clinical Research Center for Ocular Diseases;the Chongqing Key Laboratory of Ophthalmology(China)(CSTC,No.2008CA5003);Natural Science Foundation Project of Chongqing Medical University(China)(No.W0047).

摘　　要：Uveitis,a vision-threatening inflammatory disease worldwide,is closely related to resident microglia.Retinal microglia are the main immune effector cells with strong plasticity,but their role in uveitis remains unclear.N6-methyladenosine(m^(6)A)modification has been proven to be involved in the immune response.Therefore,we in this work aimed to identify the potentially crucial m^(6)A regulators of microglia in uveitis.Through the single-cell sequencing(scRNA-seq)analysis and experimental verification,we found a significant decrease in the expression of fat mass and obesity-associated protein(FTO)in retinal microglia of uveitis mice and human microglia clone 3(HMC3)cells with inflammation.Additionally,FTO knockdown was found to aggravate the secretion of inflammatory factors and the mobility/chemotaxis of microglia.Mechanistically,the RNA-seq data and rescue experiments showed that glypican 4(GPC4)was the target of FTO,which regulated microglial inflammation mediated by the TLR4/NF-κB pathway.Moreover,RNA stability assays indicated that GPC4 upregulation was mainly regulated by the downregulation of the m^(6)A“reader”YTH domain family protein 3(YTHDF3).Finally,the FTO inhibitor FB23-2 further exacerbated experimental autoimmune uveitis(EAU)inflammation by promoting the GPC4/TLR4/NF-κB signaling axis,and this could be attenuated by the TLR4 inhibitor TAK-242.Collectively,a decreased FTO could facilitate microglial inflammation in EAU,suggesting that the restoration or activation of FTO function may be a potential therapeutic strategy for uveitis.

关 键 词：Fat mass and obesity-associated protein Glypican 4 MICROGLIA N6-methyladenosine UVEITIS YTH domain Family protein 3 

分 类 号：R73[医药卫生—肿瘤]