Article

S. pombe Pbh1p: an inhibitor of apoptosis domain containing protein is essential for chromosome segregation.

Institute of Molecular Agrobiology, The National University of Singapore, Singapore.
FEBS Letters (impact factor: 3.54). 11/1999; 460(1):187-90. pp.187-90
Source: PubMed

ABSTRACT Proteins containing the baculovirus inhibitor of apoptosis repeats (BIR domains) have been identified in a wide range of species. BIR domain containing proteins are thought to inhibit caspases and thereby cause inhibition of apoptosis. A BIR domain containing protein has been recently identified by the Schizosaccharomyces pombe genome sequencing project. However, caspase-like proteins have not been found in yeasts, suggesting that the BIR domain containing proteins might play a fundamental role in cell regulation, in addition to their well-characterized role in inhibition of apoptosis. In this study, we have characterized Pbh1p, an S. pombe BIR domain containing protein. Construction and analysis of a null mutant in pbh1+ revealed that pbh1+ is essential for cell viability. Moreover, cells devoid of Pbh1p are defective in chromosome condensation and chromosome segregation. Thus, proper chromosome segregation requires the function of Pbh1p. Over-production of Pbh1p led to abnormalities in mitosis and cytokinesis, suggesting that the levels of Pbh1p are important for regulation of mitosis and cytokinesis.

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Keywords

abnormalities
 
apoptosis
 
baculovirus inhibitor
 
BIR domain
 
BIR domains
 
caspase-like proteins
 
caspases
 
cause inhibition
 
cell regulation
 
cell viability
 
cells devoid
 
chromosome condensation
 
chromosome segregation
 
fundamental role
 
inhibition
 
null mutant
 
proper chromosome segregation
 
S. pombe BIR domain
 
Schizosaccharomyces pombe genome sequencing project
 
wide range