Document Detail


Physiological pH and acidic phospholipids contribute to substrate specificity in lipidation of Atg8.
MedLine Citation:
PMID:  18544538     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Yeast Atg8 and its mammalian homolog LC3 are ubiquitin-like proteins involved in autophagy, a primary pathway for degradation of cytosolic constituents in vacuoles/lysosomes. Whereas the lipid phosphatidylethanolamine (PE) was identified as the sole in vivo target of their conjugation reactions, in vitro studies showed that the same system can mediate the conjugation of these proteins with phosphatidylserine as efficiently as with PE. Here, we show that, in contrast to PE conjugation, the in vitro phosphatidylserine conjugation of Atg8 is markedly suppressed at physiological pH. Furthermore, the addition of acidic phospholipids to liposomes also results in the preferential formation of the Atg8-PE conjugate. We have successfully captured authentic thioester intermediates, allowing us to elucidate which step in the conjugation reaction is affected by these changes in pH and membrane lipid composition. We propose that these factors contribute to the selective formation of Atg8-PE in the cell.
Authors:
Kyoko Oh-oka; Hitoshi Nakatogawa; Yoshinori Ohsumi
Related Documents :
3202098 - The profile of long-chain fatty acids in serum phospholipids: a possible indicator of c...
11426718 - Lipids of three microsporidian species and multivariate analysis of the host-parasite r...
16660788 - Galactolipid synthesis in vicia faba leaves: iv. site(s) of fatty acid incorporation in...
21665318 - Combined α-tocopherol and ascorbic acid protects against smoke-induced lung squamous m...
2536078 - Purification and characterization of neutral and acid sphingomyelinases from rat brain.
19267428 - Gas-phase ir spectroscopy of deprotonated amino acids.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2008-06-10
Journal Detail:
Title:  The Journal of biological chemistry     Volume:  283     ISSN:  0021-9258     ISO Abbreviation:  J. Biol. Chem.     Publication Date:  2008 Aug 
Date Detail:
Created Date:  2008-08-04     Completed Date:  2008-09-17     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  2985121R     Medline TA:  J Biol Chem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  21847-52     Citation Subset:  IM    
Affiliation:
Department of Cell Biology, National Institute for Basic Biology, Graduate University for Advanced Studies, Okazaki 444-8585, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Hydrogen-Ion Concentration
Liposomes / metabolism
Microtubule-Associated Proteins / metabolism*
Phosphatidylethanolamines / metabolism
Phosphatidylserines / metabolism
Phospholipids / metabolism*
Saccharomyces cerevisiae / metabolism*
Saccharomyces cerevisiae Proteins / metabolism*
Substrate Specificity
Time Factors
Ubiquitin-Conjugating Enzymes
Chemical
Reg. No./Substance:
0/ATG3 protein, S cerevisiae; 0/ATG8 protein, S cerevisiae; 0/Liposomes; 0/Microtubule-Associated Proteins; 0/Phosphatidylethanolamines; 0/Phosphatidylserines; 0/Phospholipids; 0/Saccharomyces cerevisiae Proteins; 39382-08-6/phosphatidylethanolamine; EC 6.3.2.19/Ubiquitin-Conjugating Enzymes

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Role of induced fit in enzyme specificity: a molecular forward/reverse switch.
Next Document:  Regulation of calpain activity by c-Myc through calpastatin and promotion of transformation in c-Myc...