Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1998-12-18
pubmed:databankReference
pubmed:abstractText
Eukaryotic cells have evolved a mechanism that delays the onset of anaphase until chromosomes are properly positioned on the spindle. To understand the molecular basis of such surveillance mechanism in human cells, we have cloned a full-length cDNA encoding a putative mitotic checkpoint kinase termed hBub1. Sequence comparison reveals that hBub1 is a structurally conserved protein, sharing 23% amino acid residue identity with BUB1 of budding yeast. In addition, the NH2-terminal portion (161 amino acids) of hBub1 shows a significant homology to yeast MAD3, a protein also known to be involved in the mitotic checkpoint response pathway. Northern blot analyses show that the hBub1 mRNA level is abundantly expressed in tissues or cells with a high mitotic index. When Dami cells undergo terminal differentiation after treatment with phorbol ester, hBub1 expression in this cell line is down-regulated rapidly. The hBub1 protein level is low in G1 and remains relatively constant in S, G2, and M phases. Immunofluorescence analysis shows that hBub1 protein colocalizes with a centromere-kinetochore antigen CREST in interphase, mitotic prophase, and nocodazole-treated cells. Antibody electroporation experiments show that hBub1 is an important component of the spindle checkpoint pathway. Furthermore, fluorescence in situ hybridization analysis maps the hBub1 gene to chromosome 2q12-13. Our studies suggest that hBub1 expression is restricted to proliferating cells and appears to be involved in regulating cell cycle progression. The molecular cloning of hBub1 cDNA will facilitate the study of its role in spindle checkpoint control as well as its potential role in certain genetic disorders.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1044-9523
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
877-85
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:9790499-Amino Acid Sequence, pubmed-meshheading:9790499-Base Sequence, pubmed-meshheading:9790499-Cell Cycle, pubmed-meshheading:9790499-Cell Differentiation, pubmed-meshheading:9790499-Cell Division, pubmed-meshheading:9790499-Cell Nucleus, pubmed-meshheading:9790499-Chromosome Mapping, pubmed-meshheading:9790499-Chromosomes, Human, Pair 2, pubmed-meshheading:9790499-Cloning, Molecular, pubmed-meshheading:9790499-DNA, Complementary, pubmed-meshheading:9790499-Gene Expression Regulation, pubmed-meshheading:9790499-Humans, pubmed-meshheading:9790499-Mitotic Index, pubmed-meshheading:9790499-Mitotic Spindle Apparatus, pubmed-meshheading:9790499-Molecular Sequence Data, pubmed-meshheading:9790499-Polymerase Chain Reaction, pubmed-meshheading:9790499-Protein Kinases, pubmed-meshheading:9790499-Protein-Serine-Threonine Kinases, pubmed-meshheading:9790499-Sequence Homology, Amino Acid, pubmed-meshheading:9790499-Tumor Cells, Cultured
pubmed:year
1998
pubmed:articleTitle
Human Bub1: a putative spindle checkpoint kinase closely linked to cell proliferation.
pubmed:affiliation
Department of Medicine, University of Cincinnati College of Medicine, Ohio 45267, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.