Membrane-bound annexin V isoforms (CaBP33 and CaBP37) and annexin VI in bovine tissues behave like integral membrane proteins.
FEBS Lett
; 296(2): 158-62, 1992 Jan 20.
Article
in En
| MEDLINE
| ID: mdl-1531131
ABSTRACT
The distribution of annexin V isoforms (CaBP33 and CaBP37) and of annexin VI in bovine lung, heart, and brain subfractions was investigated with special reference to the fractions of these proteins which are membrane-bound. In addition to EGTA-extractable pools of the above proteins, membranes from lung, heart, and brain contain EGTA-resistant annexins V and VI which can be solubilized with detergents (Triton X-100 or Triton X-114). A strong base like Na2CO3, which is usually effective in extracting membrane proteins, only partially solubilizes the membrane-bound, EGTA-resistant annexins analyzed here. Also, only 50-60% of the Triton X-114-soluble annexins partition in the aqueous phase, the remaining fractions being recovered in the detergent-rich phase. Altogether, these findings suggest that, by an as yet unknown mechanism, following Ca(2+)-dependent association of annexin V isoforms and annexin VI with membranes, substantial fractions of these proteins remain bound to membranes in a Ca(2+)-independent way and behave like integral membrane proteins. These results further support the possibility that the above annexins might play a role in membrane trafficking and/or in the regulation of the structural organization of membranes.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pregnancy Proteins
/
Calcium-Binding Proteins
/
Membrane Proteins
Limits:
Animals
Language:
En
Journal:
FEBS Lett
Year:
1992
Document type:
Article
Affiliation country:
Italia