Assessment of pathogenicity and functional characterization of APPL1 gene mutations in diabetic patients  

作　　者：Ping Shi Yang Tian Feng Xu Lu-Na Liu Wan-Hong Wu Ying-Zhou Shi An-Qi Dai Hang-Yu Fang Kun-Xia Li Chao Xu 

机构地区：[1]Department of Endocrinology,Shandong Provincial Hospital Affiliated to Shandong First Medical University,Jinan 250021,Shandong Province,China [2]Department of Pediatric,Yantai Yuhuangding Hospital Affiliated to Qingdao University,Yantai 264099,Shandong Province,China

出　　处：《World Journal of Diabetes》2024年第2期275-286,共12页世界糖尿病杂志（英文版）（电子版）

基　　金：Supported by the National Natural Science Foundation,No.81974124;and Taishan Scholar Project,No.tsqn20161071.

摘　　要：BACKGROUND Adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 1(APPL1)plays a crucial role in regulating insulin signaling and glucose metabolism.Mutations in the APPL1 gene have been associated with the development of maturity-onset diabetes of the young type 14(MODY14).Currently,only two mutations[c.1655T>A(p.Leu552*)and c.281G>A p.(Asp94Asn)]have been identified in association with this disease.Given the limited understanding of MODY14,it is imperative to identify additional cases and carry out comprehensive research on MODY14 and APPL1 mutations.AIM To assess the pathogenicity of APPL1 gene mutations in diabetic patients and to characterize the functional role of the APPL1 domain.METHODS Patients exhibiting clinical signs and a medical history suggestive of MODY were screened for the study.Whole exome sequencing was performed on the patients as well as their family members.The pathogenicity of the identified APPL1 variants was predicted on the basis of bioinformatics analysis.In addition,the pathogenicity of the novel APPL1 variant was preliminarily evaluated through in vitro functional experiments.Finally,the impact of these variants on APPL1 protein expression and the insulin pathway were assessed,and the potential mechanism underlying the interaction between the APPL1 protein and the insulin receptor was further explored.RESULTS A total of five novel mutations were identified,including four missense mutations(Asp632Tyr,Arg633His,Arg532Gln,and Ile642Met)and one intronic mutation(1153-16A>T).Pathogenicity prediction analysis revealed that the Arg532Gln was pathogenic across all predictions.The Asp632Tyr and Arg633His variants also had pathogenicity based on MutationTaster.In addition,multiple alignment of amino acid sequences showed that the Arg532Gln,Asp632Tyr,and Arg633His variants were conserved across different species.Moreover,in in vitro functional experiments,both the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations were found to downregulate the expression of APP

关 键 词：Adaptor protein phosphotyrosine interacting with PH domain and leucine zipper 1 Maturity-onset diabetes of the young Bioinformatics analysis Gene mutation DOMAIN 

分 类 号：R587.2[医药卫生—内分泌]