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Calcium tips the balance: a microtubule plus end to lattice binding switch operates in the carboxyl terminus of BPAG1n4.

ABSTRACT: Microtubules (MTs) are integral to numerous cellular functions, such as cell adhesion, differentiation and intracellular transport. Their dynamics are largely controlled by diverse MT-interacting proteins, but the signalling mechanisms that regulate these interactions remain elusive. In this report, we identify a rapid, calcium-regulated switch between MT plus end interaction and lattice binding within the carboxyl terminus of BPAG1n4. This switch is EF-hand dependent, and mutations of the EF-hands abolish this dynamic behaviour. Our study thus uncovers a new, calcium-dependent regulatory mechanism for a spectraplakin, BPAG1n4, at the MT plus end.

SUBMITTER: Kapur M

PROVIDER: S-EPMC3492708 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Calcium tips the balance: a microtubule plus end to lattice binding switch operates in the carboxyl terminus of BPAG1n4.

Kapur Mridu M Wang Wei W Maloney Michael T MT Millan Ivan I Lundin Victor F VF Tran Thuy-An TA Yang Yanmin Y

EMBO reports 20120921 11

Microtubules (MTs) are integral to numerous cellular functions, such as cell adhesion, differentiation and intracellular transport. Their dynamics are largely controlled by diverse MT-interacting proteins, but the signalling mechanisms that regulate these interactions remain elusive. In this report, we identify a rapid, calcium-regulated switch between MT plus end interaction and lattice binding within the carboxyl terminus of BPAG1n4. This switch is EF-hand dependent, and mutations of the EF-ha ...[more]

PMID: 22995871

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