Cryo-EM structure of the plant 26S proteasome  

作　　者：Susanne Kandolf Irina Grishkovskaya Katarina Belacic Derek L.Bolhuis Sascha Amann Brent Foster Richard Imre Karl Mechtler Alexander Schleiffer Hemant D.Tagare Ellen D.Zhong Anton Meinhart Nicholas G.Brown David Haselbach 

机构地区：[1]Research Institute of Molecular Pathology(IMP),Vienna BioCenter(VBC),Campus-Vienna-BioCenter 1,1030 Vienna,Austria [2]Department of Radiology and Biomedical Imaging,Yale University,New Haven,CT 06510,USA [3]Department of Pharmacology and Lineberger Comprehensive Cancer Center,University of North Carolina School of Medicine,Chapel Hill,NC 27599,USA [4]Computer Science and Artificial Intelligence Laboratory,Massachusetts Institute of Technology,Cambridge,MA 02139,USA [5]Vienna BioCenter PhD Program,Doctoral School of the University at Vienna and Medical University of Vienna,Vienna BioCenter(VBC),Vienna,Austria [6]Institute of Physical Chemistry,University of Freiburg,Albertstraße 21,Freiburg 79104,Germany [7]CIBSS Centre for Integrative Biological Signalling Studies,University of Freiburg,Freiburg,Germany

出　　处：《Plant Communications》2022年第3期116-126,共11页植物通讯（英文）

基　　金：D.L.B.and N.G.B.are supported by NIH R35GM128855 and the Univer-sity Cancer Research Fund(UCRF);H.D.T.and B.F.were supported by NIH grant R01GM125769;The IMP,the whole Haselbach lab,and espe-cially S.K.are supported by Boehringer Ingelheim.

摘　　要：Targeted proteolysis is a hallmark of life.It is especially important in long-lived cells that can be found in higher eukaryotes,like plants.This task is mainly fulfilled by the ubiquitin–proteasome system.Thus,proteolysis by the 26S proteasome is vital to development,immunity,and cell division.Although the yeast and animal proteasomes are well characterized,there is only limited information on the plant proteasome.We determined the first plant 26S proteasome structure from Spinacia oleracea by single-particle electron cryogenic microscopy at an overall resolution of 3.3 A°.We found an almost identical overall architecture of the spinach proteasome compared with the known structures from mammals and yeast.Nevertheless,we noticed a structural difference in the proteolytic active b1 subunit.Furthermore,we uncovered an unseen compression state by characterizing the proteasome’s conformational landscape.We suspect that this new conformation of the 20S core protease,in correlation with a partial opening of the unoccupied gate,may contribute to peptide release after proteolysis.Our data provide a structural basis for the plant proteasome,which is crucial for further studies.

关 键 词：26S proteasome SPINACH UPS CRYO-EM conformational landscape 

分 类 号：Q94[生物学—植物学]