The membrane spanning domain of beta-1,4-galactosyltransferase specifies trans Golgi localization.
AUTOR(ES)
Nilsson, T
RESUMO
Chimeric cDNAs were constructed so as to generate hybrid proteins in which different parts of the N-terminal domain of the human invariant chain were replaced by equivalent sequences from the trans Golgi resident enzyme, beta-1,4-galactosyltransferase. The cytoplasmic and membrane spanning domains of galactosyltransferase were found to be sufficient to retain all of the hybrid invariant chain in trans Golgi cisternae as judged by indirect immunofluorescence, treatment with brefeldin A and immuno-electron microscopy. As few as ten amino acids corresponding to the lumenal half of the membrane spanning domain of the Golgi enzyme sufficed to localize most of the hybrid invariant chain to the trans cisternae. A cytoplasmic domain was necessary for complete retention as assessed by flow cytofluorometry but could be provided either by galactosyltransferase or by invariant chain. This suggests that the cytoplasmic domain plays a role accessory to the membrane spanning domain, the latter mediating compartmental specificity.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=453088Documentos Relacionados
- Localization of the long form of beta-1,4-galactosyltransferase to the plasma membrane and Golgi complex of 3T3 and F9 cells by immunofluorescence confocal microscopy.
- Cell surface and Golgi pools of beta-1,4-galactosyltransferase are differentially regulated during embryonal carcinoma cell differentiation.
- Expression of bovine beta-1,4-galactosyltransferase cDNA in COS-7 cells.
- Molecular analysis of cell surface beta-1,4-galactosyltransferase function during cell migration.
- Golgi retention of a trans-Golgi membrane protein, galactosyltransferase, requires cysteine and histidine residues within the membrane-anchoring domain.
