BUB3

This gene encodes a protein involved in spindle checkpoint function. The encoded protein contains four WD repeat domains and has sequence similarity with the yeast BUB3 protein. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. [provided by RefSeq, Jul 2008]

Full Name

BUB3, Mitotic Checkpoint Protein

Function

Has a dual function in spindle-assembly checkpoint signaling and in promoting the establishment of correct kinetochore-microtubule (K-MT) attachments. Promotes the formation of stable end-on bipolar attachments. Necessary for kinetochore localization of BUB1. Regulates chromosome segregation during oocyte meiosis. The BUB1/BUB3 complex plays a role in the inhibition of anaphase-promoting complex or cyclosome (APC/C) when spindle-assembly checkpoint is activated and inhibits the ubiquitin ligase activity of APC/C by phosphorylating its activator CDC20. This complex can also phosphorylate MAD1L1.

Biological Process

Anaphase-promoting complex-dependent catabolic process Source: Reactome
Attachment of spindle microtubules to kinetochore Source: UniProtKB
Cell division Source: UniProtKB-KW
Meiotic cell cycle Source: UniProtKB-KW
Mitotic sister chromatid segregation Source: Ensembl
Mitotic spindle assembly checkpoint Source: GO_Central
Mitotic spindle organization Source: Reactome
Protein localization to kinetochore Source: UniProtKB
Regulation of exit from mitosis Source: Reactome
Regulation of mitotic cell cycle phase transition Source: Reactome
Ubiquitin-dependent protein catabolic process Source: Reactome

Cellular Location

Nucleus; Kinetochore. Starts to localize at kinetochores in prometaphase I (Pro-MI) stage and maintains the localization until the metaphase I-anaphase I (MI-AI) transition.

PTM

Poly-ADP-ribosylated by PARP1.