Transient phosphorylation of tumor associated microtubule associated protein (TMAP)/cytoskeleton associated protein 2 (CKAP2) at Thr-596 during early phases of mitosis.
10.3858/emm.2008.40.4.377
- Author:
Kyung Uk HONG
1
;
Yong Bock CHOI
;
Jung Hwa LEE
;
Hyun Jun KIM
;
Hye Rim KWON
;
Yeon Sun SEONG
;
Heung Tae KIM
;
Joobae PARK
;
Chang Dae BAE
;
Kyeong Man HONG
Author Information
1. Department of Molecular Cell Biology and Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Korea.
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
antibodies, monoclonal;
cell cycle;
CKAP2 protein, human;
fluorescent antibody technique, direct;
phosphorylation
- MeSH:
Amino Acid Sequence;
Animals;
Antibodies, Monoclonal/metabolism/pharmacology;
Cell Cycle/physiology;
Cells, Cultured;
Cytoskeletal Proteins/chemistry/immunology/*metabolism/physiology;
Epitope Mapping;
Hela Cells;
Humans;
Mice;
Mitosis/*physiology;
Molecular Sequence Data;
Phosphorylation;
Protein-Serine-Threonine Kinases/*metabolism;
Sequence Homology, Amino Acid;
Threonine/metabolism
- From:Experimental & Molecular Medicine
2008;40(4):377-386
- CountryRepublic of Korea
- Language:English
-
Abstract:
Tumor associated microtubule associated protein (TMAP), also known as cytoskeleton associated protein 2 (CKAP2) is a mitotic spindle-associated protein whose expression is cell cycle-regulated and also frequently deregulated in cancer cells. Two monoclonal antibodies (mAbs) against TMAP/CKAP2 were produced: B-1-13 and D-12-3. Interestingly, the reactivity of mAb D-12-3 to TMAP/CKAP2 was markedly decreased specifically in mitotic cell lysate. The epitope mapping study showed that mAb D-12-3 recognizes the amino acid sequence between 569 and 625 and that phosphorylation at T596 completely abolishes the reactivity of the antibody, suggesting that the differential reactivity originates from the phosphorylation status at T596. Immunofluorescence staining showed that mAb D-12-3 fails to detect TMAP/CKAP2 in mitotic cells between prophase and metaphase, but the staining becomes evident again in anaphase, suggesting that phosphorylation at T596 occurs transiently during early phases of mitosis. These results suggest that the cellular functions of TMAP/CKAP2 might be regulated by timely phosphorylation and dephosphorylation during the course of mitosis.
