BUB3 Human Recombinant Protein

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]

BUB3: 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. Interacts with BUB1 and BUBR1. The BUB1/BUB3 complex interacts with MAD1L1. Belongs to the WD repeat BUB3 family. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: Cell cycle regulation

Chromosomal Location of Human Ortholog: 10q26

Cellular Component: nucleoplasm; kinetochore; cytosol

Molecular Function: protein binding

Biological Process: negative regulation of ubiquitin-protein ligase activity during mitotic cell cycle; regulation of ubiquitin-protein ligase activity during mitotic cell cycle; mitotic sister chromatid segregation; meiotic cell cycle; anaphase-promoting complex-dependent proteasomal ubiquitin-dependent protein catabolic process; cell division; mitotic cell cycle spindle assembly checkpoint; mitotic cell cycle; attachment of spindle microtubules to kinetochore