Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
2003-5-26
pubmed:abstractText
PEN-2 is an integral membrane protein that is a necessary component of the gamma-secretase complex, which is central in the pathogenesis of Alzheimer's disease and is also required for Notch signaling. In the absence of PEN-2, Notch signaling fails to guide normal development in Caenorhabditis elegans, and amyloid beta peptide is not generated from the amyloid precursor protein. Human PEN-2 is a 101-amino acid protein containing two putative transmembrane domains. To understand its interaction with other gamma-secretase components, it is important to know the membrane topology of each member of the complex. To characterize the membrane topology of PEN-2, we introduced single amino acid changes in each of the three hydrophilic regions of PEN-2 to generate N-linked glycosylation sites. We found that the N-linked glycosylation sites present in the N- and C-terminal domains of PEN-2 were utilized, whereas a site in the hydrophilic "loop" region connecting the two transmembrane domains was not. The addition of a carbohydrate structure in the N-terminal domain of PEN-2 prevented association with presenilin 1, whereas glycosylation in the C-terminal region of PEN-2 did not, suggesting that the N-terminal domain is important for interactions with presenilin 1. Immunofluorescence microscopy with selective permeabilization of the plasma membrane of cells expressing epitope-tagged forms of PEN-2 confirmed the lumenal location of both the N and C termini. A protease protection assay also demonstrated that the loop domain of PEN-2 is cytosolic. Thus, PEN-2 spans the membrane twice, with the N and C termini facing the lumen of the endoplasmic reticulum.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
20117-23
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Membrane topology of gamma-secretase component PEN-2.
pubmed:affiliation
Department of Microbiology, The Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia 19104, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't