protein regulator of cytokinesis 1 (PRC1)

Function: - key regulator of cytokinesis - cross-links antiparrallel microtubules at an average distance of 35 nM - essential for controlling the spatiotemporal formation of the midzone & successful cytokinesis - required for KIF14 localization to the central spindle & midbody - required to recruit PLK1 to the spindle - stimulates PLK1 phosphorylation of RACGAP1 to allow recruitment of ECT2 to the central spindle - phosphorylation by CDK1 in early mitosis holds PRC1 in an inactive monomeric state - phosphorylation by CDK1 prevents PLK1-binding - CDK1 is degraded at anaphase & dephosphorylation - during the metaphase to anaphase transition, PRC1 is dephosphorylated, promoting interaction with KIF4A, which then translocates PRC1 along mitotic spindles to the plus ends of antiparallel interdigitating microtubules - dephosphorylation also promotes microtubule-bundling activity by allowing dimerization. - KIF4A translocates PRC1 to the plus ends of interdigitating spindle microtubules during the metaphase to anaphase transition - microtubule-binding & bundling protein both in vivo & in vitro - interacts with the C-terminal Rho-GAP domain & the basic region of RACGAP1 - interaction with RACGAP1 inhibits its GAP activity towards CDC42 - interacts separately via its N-terminal region with the C-terminus of CENPE, KIF4A, KIF23 during late mitosis - phosphorylation: very weak in G1/S phase cells, reaches a maximum during mitosis Structure: - homodimer - microtubule binding occurs via a basic patch in the central spectrin-like domain & requires also the C-terminal domain - belongs to the MAP65/ASE1 family, Compartment: - nucleus of interphase cells - cytoplasm - during mitosis associated with mitotic spindle poles - localizes with cell midbody during cytokinesis Alternative splicing: named isoforms=4

Properties

SIZE: MW = 72 kD entity length = 620 aa COMPARTMENT: cytoplasm cell nucleus MOTIF: Dimerization {1-341} MOTIF: coiled coil {96-133} Ser phosphorylation site {S195} coiled coil {211-304} Ser phosphorylation site {S265} Spectrin-fold {342-466} MOTIF: binding site SITE: 377-377 FOR-BINDING-OF: tubulin coiled coil {383-463} binding site SITE: 387-387 FOR-BINDING-OF: tubulin Arg/Lys rich {467-620} MOTIF: Thr phosphorylation site {T470} Thr phosphorylation site {T481} Ser phosphorylation site {S501} Ser phosphorylation site {S513} Ser phosphorylation site {S571} Ser phosphorylation site {S592} Ser phosphorylation site {S615} Thr phosphorylation site {T616}

Database Correlations

OMIM 603484 UniProt O43663 Pfam PF03999 Entrez Gene 9055 Kegg hsa:9055

References

UniProt :accession O43663