AlphaFold2 assists in providing novel mechanistic insights into the interactions among the LUBAC subunits  

作　　者：Chenchen Wang Chunying Gu Ying Lv Hongyu Liu Yanan Wang Yongmei Zuo Guangyu Jiang Lili Liu Jiafu Liu 

机构地区：[1]College of Veterinary Medicine,Northeast Agricultural University,Harbin 150030,China [2]Department of Medical Laboratory Science and Technology,Harbin Medical University-Daqing,Daqing 163319,China [3]College of Life Sciences,Northeast Agricultural University,Harbin 150030,China [4]Preventive and Control Center for Animal Disease of Heilongjiang Province,Harbin 150069,China [5]College of Basic Medical Sciences,Harbin Medical University-Daqing,Daqing 163319,China [6]Heilongjiang Institute of Animal Health Inspection,Harbin 150006,China

出　　处：《Acta Biochimica et Biophysica Sinica》2024年第7期1034-1043,共10页生物化学与生物物理学报（英文版）

基　　金：supported by the Scientific Research Grant from Harbin Medical University-Daqing.

摘　　要：The linear ubiquitin chain assembly complex(LUBAC)is the only known E3 ligase complex in which the ubiquitin-like(UBL)domains of SHARPIN and HOIL-1L interact with HOIP to determine the structural stability of LUBAC.The interactions between subunits within LUBAC have been a topic of extensive research.However,the impact of the LTM motif on the interaction between the UBL domains of SHARPIN and HOIL-1L with HOIP remains unclear.Here,we discover that the absence of the LTM motif in the AlphaFold2-predicted LUBAC structure alters the HOIP-UBA structure.We employ GeoPPI to calculate the changes in binding free energy(ΔG)caused by single-point mutations between subunits,simulating their protein-protein interactions.The results reveal that the presence of the LTM motif decreases the interaction between the UBL domains of SHARPIN and HOIL-1L with HOIP,leading to a decrease in the structural stability of LUBAC.Furthermore,using the AlphaFold2-predicted results,we find that HOIP(629‒695)and HOIP-UBA bind to both sides of HOIL-1L-UBL,respectively.The experiments of Gromacs molecular dynamics simulations,SPR and ITC demonstrate that the elongated domain formed by HOIP(629‒695)and HOIP-UBA,hereafter referred to as the HOIP(466‒695)structure,interacts with HOIL-1L-UBL to form a structurally stable complex.These findings illustrate the collaborative interaction between HOIP-UBA and HOIP(629‒695)with HOIL-1L-UBL,which influences the structural stability of LUBAC.

关 键 词：LUBAC LTM motif HOIP-UBA HOIL-1L-UBL SHARPIN-UBL 

分 类 号：Q5[生物学—生物化学] Q6