PubMed:9427624 JSONTXT

{"target":"https://pubannotation.org/docs/sourcedb/PubMed/sourceid/9427624","sourcedb":"PubMed","sourceid":"9427624","source_url":"http://www.ncbi.nlm.nih.gov/pubmed/9427624","text":"TAP- and tapasin-dependent HLA-E surface expression correlates with the binding of an MHC class I leader peptide.\nBACKGROUND: The human major histocompatibility complex (MHC) class lb molecule HLA-E is transcribed in most tissues but little is known about its localisation within the cell. We have recently shown that HLA-E binds signal-sequence-derived peptides from human MHC class I molecules in vitro.\nRESULTS: Using a newly characterised antibody recognising HLA-E, we show that HLA-E is expressed at the cell surface. We demonstrate that HLA-E surface expression is correlated with the presence of MHC class I molecules which provide suitable leader sequence peptides capable of binding to HLA-E. Further studies on the interaction of HLA-E with molecules in the endoplasmic reticulum revealed that HLA-E associates with the transporter associated with antigen processing (TAP) and calreticulin, and that HLA-E expression is TAP-dependent and tapasin-dependent. In addition, HLA-E dissociates from TAP upon binding of MHC class I leader sequence peptides.\nCONCLUSION: These experiments establish that surface expression of HLA-E is regulated by the binding of a restricted pool of peptides from the leader sequence of MHC class I molecules. The correlation between HLA-E and MHC class I surface expression might be relevant to the function of HLA-E. Our results also show that, although these HLA-E binding peptides are derived from signal sequences, they may be released back into the cytosol and subsequently translocated by the TAP complex and loaded onto HLA-E molecules.","tracks":[{"project":"AIMed","denotations":[{"id":"T1","span":{"begin":0,"end":3},"obj":"protein"},{"id":"T2","span":{"begin":9,"end":16},"obj":"protein"},{"id":"T3","span":{"begin":27,"end":32},"obj":"protein"},{"id":"T4","span":{"begin":193,"end":198},"obj":"protein"},{"id":"T5","span":{"begin":318,"end":323},"obj":"protein"},{"id":"T6","span":{"begin":484,"end":489},"obj":"protein"},{"id":"T7","span":{"begin":544,"end":549},"obj":"protein"},{"id":"T8","span":{"begin":696,"end":701},"obj":"protein"},{"id":"T9","span":{"begin":741,"end":746},"obj":"protein"},{"id":"T10","span":{"begin":805,"end":810},"obj":"protein"},{"id":"T11","span":{"begin":879,"end":882},"obj":"protein"},{"id":"T12","span":{"begin":911,"end":916},"obj":"protein"},{"id":"T13","span":{"begin":931,"end":934},"obj":"protein"},{"id":"T14","span":{"begin":981,"end":986},"obj":"protein"},{"id":"T15","span":{"begin":1004,"end":1007},"obj":"protein"},{"id":"T16","span":{"begin":1129,"end":1134},"obj":"protein"},{"id":"T17","span":{"begin":1271,"end":1276},"obj":"protein"},{"id":"T18","span":{"begin":1349,"end":1354},"obj":"protein"},{"id":"T19","span":{"begin":1399,"end":1404},"obj":"protein"},{"id":"T20","span":{"begin":1537,"end":1540},"obj":"protein"},{"id":"T21","span":{"begin":1565,"end":1570},"obj":"protein"}],"attributes":[{"subj":"T1","pred":"source","obj":"AIMed"},{"subj":"T2","pred":"source","obj":"AIMed"},{"subj":"T3","pred":"source","obj":"AIMed"},{"subj":"T4","pred":"source","obj":"AIMed"},{"subj":"T5","pred":"source","obj":"AIMed"},{"subj":"T6","pred":"source","obj":"AIMed"},{"subj":"T7","pred":"source","obj":"AIMed"},{"subj":"T8","pred":"source","obj":"AIMed"},{"subj":"T9","pred":"source","obj":"AIMed"},{"subj":"T10","pred":"source","obj":"AIMed"},{"subj":"T11","pred":"source","obj":"AIMed"},{"subj":"T12","pred":"source","obj":"AIMed"},{"subj":"T13","pred":"source","obj":"AIMed"},{"subj":"T14","pred":"source","obj":"AIMed"},{"subj":"T15","pred":"source","obj":"AIMed"},{"subj":"T16","pred":"source","obj":"AIMed"},{"subj":"T17","pred":"source","obj":"AIMed"},{"subj":"T18","pred":"source","obj":"AIMed"},{"subj":"T19","pred":"source","obj":"AIMed"},{"subj":"T20","pred":"source","obj":"AIMed"},{"subj":"T21","pred":"source","obj":"AIMed"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"AIMed","color":"#ec93b3","default":true}]}]}}