Immuno-electron microscopy localizes Caenorhabditis elegans vitellogenins along the classic exocytosis route  

作　　者：Chao Zhai Nan Zhang Xi-Xia Li Xue-Ke Tan Fei Sun Meng-Qiu Dong 

机构地区：[1]National Institute of Biological Sciences,Beijing 102206,China [2]School of Life Sciences,Peking University,Beijing 100871,China [3]Tsinghua Institute of Multidisciplinary Biomedical Research,Tsinghua University,Beijing 100084,China [4]Center for Biological Imaging,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China [5]National Key Laboratory of Biomacromolecules,CAS Center for Excellence in Biomacromolecules,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China [6]University of Chinese Academy of Sciences,School of Life Science,Beijing 100049,China

出　　处：《Life Metabolism》2024年第6期17-32,共16页生命代谢（英文）

基　　金：funded by the National Natural Science Foundation of China(NSFC-ISF 32061143020 to M.Q.D.,31925026 to F.S.,and 31501160 to X.X.L.);the Ministry of Science and Technology of the People's Republic of China(institutional grants to NIBS,Beijing,a fund of the National High-Level Talents Special Support Program to M.Q.D.);Beijing Municipal Science and Technology Commission(institutional grants to NIBS,Beijing and a fund for cultivation and development of innovation base to M.Q.D.).

摘　　要：Vitellogenins(VITs)are the most abundant proteins in adult hermaphrodite Caenorhabditis elegans.VITs are synthesized in the intes-tine,secreted to the pseudocoelom,matured into yolk proteins,and finally deposited in oocytes as nutrients for progeny development.How VITs are secreted out of the intestine remains unclear.Using immuno-electron microscopy(immuno-EM),we localize intestinal VITs along an exocytic pathway consisting of the rough endoplasmic reticulum(ER),the Golgi,and the lipid bilayer-bounded VIT vesicles(VVs).This suggests that the classic exocytotic pathway mediates the secretion of VITs from the intestine to the pseudocoe-lom.We also show that pseudocoelomic yolk patches(PYPs)are membrane-less and amorphous.The different VITs/yolk proteins are packed as a mixture into the above structures.The size of VVs can vary with the VIT levels and the age of the worm.On adult Day 2(AD 2),intestinal VVs(~200 nm in diameter)are smaller than gonadal yolk organelles(YOs,~500 nm in diameter).VVs,PYPs,and YOs share a uniform medium electron density by conventional EM.The morphological profiles documented in this study serve as a refer-ence for future studies of VITs/yolk proteins.

关 键 词：VITELLOGENIN YOLK immuno-EM EXOCYTOSIS Caenorhabditis elegans 

分 类 号：TH742[机械工程—光学工程]