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Nuclear localization of clathrin involves a labile helix outside the trimerization domain.

ABSTRACT: Clathrin is a trimeric protein involved in receptor-mediated-endocytosis, but can function as a non-trimer outside of endocytosis. We have discovered that the subcellular distribution of a clathrin cysteine mutant we previously studied is altered and a proportion is also localized to nuclear spaces. MALS shows C1573A hub is a mixture of trimer-like and detrimerized molecules. The X-ray structure of the trimerization domain reveals that without light chains, a helix harboring cysteine-1573 is reoriented. We propose clathrin has a detrimerization switch, which suggests clathrin topology can be altered naturally for new functions.

SUBMITTER: Ybe JA

PROVIDER: S-EPMC3543496 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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Nuclear localization of clathrin involves a labile helix outside the trimerization domain.

Ybe Joel A JA Fontaine Sarah N SN Stone Todd T Nix Jay J Lin Xiaoyan X Mishra Sanjay S

FEBS letters 20121121 2

Clathrin is a trimeric protein involved in receptor-mediated-endocytosis, but can function as a non-trimer outside of endocytosis. We have discovered that the subcellular distribution of a clathrin cysteine mutant we previously studied is altered and a proportion is also localized to nuclear spaces. MALS shows C1573A hub is a mixture of trimer-like and detrimerized molecules. The X-ray structure of the trimerization domain reveals that without light chains, a helix harboring cysteine-1573 is reo ...[more]

PMID: 23178717

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