Role of p97 and Syntaxin 5 in the Assembly of Transitional Endoplasmic Reticulum
AUTOR(ES)
Roy, Line
FONTE
The American Society for Cell Biology
RESUMO
Transitional endoplasmic reticulum (tER) consists of confluent rough and smooth endoplasmic reticulum (ER) domains. In a cell-free incubation system, low-density microsomes (1.17 g cc−1) isolated from rat liver homogenates reconstitute tER by Mg2+GTP- and Mg2+ATP-hydrolysis–dependent membrane fusion. The ATPases associated with different cellular activities protein p97 has been identified as the relevant ATPase. The ATP depletion by hexokinase or treatment with either N-ethylmaleimide or anti-p97 prevented assembly of the smooth ER domain of tER. High-salt washing of low-density microsomes inhibited assembly of the smooth ER domain of tER, whereas the readdition of purified p97 with associated p47 promoted reconstitution. The t-SNARE syntaxin 5 was observed within the smooth ER domain of tER, and antisyntaxin 5 abrogated formation of this same membrane compartment. Thus, p97 and syntaxin 5 regulate assembly of the smooth ER domain of tER and hence one of the earliest membrane differentiated components of the secretory pathway.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=14937Documentos Relacionados
- Tyrosine phosphorylation of p97 regulates transitional endoplasmic reticulum assembly in vitro
- Recruitment of the p97 ATPase and ubiquitin ligases to the site of retrotranslocation at the endoplasmic reticulum membrane
- Mammalian Sec23p homologue is restricted to the endoplasmic reticulum transitional cytoplasm.
- An isoform of the Golgi t-SNARE, syntaxin 5, with an endoplasmic reticulum retrieval signal.
- Dynamics of Transitional Endoplasmic Reticulum Sites in Vertebrate Cells
