Human INCENP colocalizes with the Aurora-B/AIRK2 kinase on chromosomes and is overexpressed in tumour cells.
The inner centromere protein (INCENP), which has previously been described in chicken, frog and mouse, is required for correct chromosome segregation and cytokinesis. We have identified the human INCENP gene by library screening and reverse transcription-polymerase chain reaction (RT-PCR) and localized it to chromosomal region 11q12. HsINCENP is a single-copy gene that consists of 17 exons and covers 25 kb of genomic DNA. The gene is expressed at highest levels in the colon, testis and prostate, consistent with its likely role in cell proliferation. HsINCENP encodes a highly basic protein of 915 amino acids that localizes to metaphase chromosomes and to the mitotic spindle and equatorial cortex at anaphase. Recently we showed that INCENP is stockpiled in a complex with the Aurora-B/XAIRK2 kinase in Xenopus eggs. Here we demonstrate that, consistent with such an interaction, the two proteins colocalize on human metaphase chromosomes. Levels of Aurora-B are increased in several human cancers, and we show here that HsINCENP protein levels are also significantly increased in several colorectal cancer cell lines.
Adams
R R
RR
Wellcome Trust Centre for Cell Biology, University of Edinburgh, UK. richard.adams@ed.ac.uk
Eckley
D M
DM
Vagnarelli
P
P
Wheatley
S P
SP
Gerloff
D L
DL
Mackay
A M
AM
Svingen
P A
PA
Kaufmann
S H
SH
Earnshaw
W C
WC
D000595:Amino Acid Sequence; D000818:Animals; D064107:Aurora Kinase B; D064127:Aurora Kinases; D015139:Blotting, Southern; D002478:Cells, Cultured; D002503:Centromere / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D002877:Chromosomes, Human / Q000378:metabolism* / Q000648:ultrastructure; D003001:Cloning, Molecular; D003110:Colonic Neoplasms / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D008677:Metaphase; D051379:Mice; D008969:Molecular Sequence Data; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014982:Xenopus laevis
D002868:Chromosomal Proteins, Non-Histone; C083767:INCENP protein, human; C513185:Incenp protein, mouse; D012333:RNA, Messenger; C576921:AURKB protein, human; C576924:Aurkb protein, mouse; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases