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. 1989 May;86(10):3798–3802. doi: 10.1073/pnas.86.10.3798

Calcium channel activity of purified human synexin and structure of the human synexin gene.

A L Burns 1, K Magendzo 1, A Shirvan 1, M Srivastava 1, E Rojas 1, M R Alijani 1, H B Pollard 1
PMCID: PMC287228  PMID: 2542947

Abstract

Synexin is a calcium-dependent membrane binding protein that not only fuses membranes but also acts as a voltage-dependent calcium channel. We have isolated and sequenced a set of overlapping cDNA clones for human synexin. The derived amino acid sequence of synexin reveals strong homology in the C-terminal domain with a previously identified class of calcium-dependent membrane binding proteins. These include endonexin II, lipocortin I, calpactin I heavy chain (p36), protein II, and calelectrin 67K. The Mr 51,000 synexin molecule can be divided into a unique, highly hydrophobic N-terminal domain of 167 amino acids and a conserved C-terminal region of 299 amino acids. The latter domain is composed of alternating hydrophobic and hydrophilic segments. Analysis of the entire structure reveals possible insights into such diverse properties as voltage-sensitive calcium channel activity, ion selectivity, affinity for phospholipids, and membrane fusion.

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Selected References

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