Selective and programmed cleavage of GPI-anchored proteins from the surface membrane by phospholipase C.
Biochim Biophys Acta
; 1818(1): 117-24, 2012 Jan.
Article
in En
| MEDLINE
| ID: mdl-22024023
ABSTRACT
Many surface proteins of eukaryotic cells are tethered to the membrane by a GPI-anchor which is enzymatically cleavable. Here, we investigate cleavage and release of different GPI-proteins by phospholipase C from the outer membrane of the ciliate Paramecium tetraurelia. Our data indicate that different GPI-proteins are not equally cleaved as proteins of the surface antigen family are preferentially released in vitro compared to several smaller GPI-proteins. Likewise, the analysis of culture medium indicates exclusive in vivo release of surface antigens by two phospholipase C isoforms (PLC2 and PLC6). This suggests that phospholipase C shows affinity for select groups of GPI-anchored proteins. Our data also reveal an up-regulation of PLC isoforms in GPI-anchored protein cleavage during antigenic switching. As a consequence, silencing of these PLCs leads to a drastic decrease of antigen concentration in the medium. These results suggest a higher order of GPI-regulation by phospholipase C as cleavage occurs programmed and specific for single GPI-proteins instead of an unspecific shedding of the entire surface membrane GPI-content.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Type C Phospholipases
/
Cell Membrane
/
Paramecium tetraurelia
/
Isoenzymes
/
Membrane Proteins
/
Antigens, Surface
Language:
En
Journal:
Biochim Biophys Acta
Year:
2012
Type:
Article
Affiliation country:
Germany