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Epitope mapping of annexin I: antibodies that compete with phospholipids and calcium recognize amino acids 42-99.

ABSTRACT: To understand further the structural basis of phospholipid binding by annexin I, three monoclonal antibodies that compete with Ca2+ and phospholipids for binding of annexin I were used to screen an expression library containing fragments of bovine annexin I cDNA. In all, 15 clones were isolated, and all contain overlapping fragments of the cDNA. The smallest unit common to all of the clones encodes amino acids 42-99 of annexin I, representing a portion of the first repeat domain. This demonstrates that recognition of a single domain of annexin I is sufficient to completely block phospholipid binding, and implies that the first repeat may contribute to phospholipid binding by annexin I.

SUBMITTER: Ernst JD

PROVIDER: S-EPMC1132201 | biostudies-other | 1993 Jan

REPOSITORIES: biostudies-other

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