TY - JOUR
T1 - Trypanosoma brucei 14-3-3I and II proteins predominantly form a heterodimer structure that acts as a potent cell cycle regulator in vivo
AU - Inoue, Masahiro
AU - Yasuda, Kouichi
AU - Uemura, Haruki
AU - Yasaka, Natsumi
AU - Schnaufer, Achim
AU - Yano, Mihiro
AU - Kido, Hiroshi
AU - Kohda, Daisuke
AU - Doi, Hirofumi
AU - Fukuma, Toshihide
AU - Tsuji, Akihiko
AU - Horikoshi, Nobuo
N1 - Funding Information:
This work was supported by Ministry of Education, Culture, Sports, Science and Technology grant 23590500 and a collaboration grant of the Institute for Enzyme research, Tokushima (24-12) to M.I.
PY - 2013/5
Y1 - 2013/5
N2 - Hetero- and homodimerization of 14-3-3 proteins demonstrate distinctive functions in mammals and plants. Trypanosoma brucei 14-3-3I and II (Tb14-3-3I and II) play pivotal roles in motility, cytokinesis and the cell cycle; however, the significance and the mechanism of Tb14-3-3 dimerization are remained to be elucidated. We found that ectopically expressed epitope-tagged Tb14-3-3I and II proteins formed hetero- and homodimers with endogenous Tb14-3-3I and II proteins. However, we also found the ability to form hetero- or homodimers between Tb14-3-3I and II proteins was clearly affected by the sequence and location of the epitope tag used. We found a blue native polyacrylamide gel electrophoresis system followed by western blotting may distinguish monomer from dimer structure, and stable from unstable conformation of Tb14-3-3. Combined with co-immunoprecipitation results, we revealed that Tb14-3-3 proteins mainly existed as heterodimeric form. Furthermore, co-overexpression of Tb14-3-3I and II proteins in T. brucei induced aberrant numbers of organelles in cells, but overexpression of either isoform alone rarely produced such morphology. These results suggest that heterodimers play more significant roles than homodimers not only in the maintenance of steady-state levels of the 14-3-3 proteins but also in the regulation of cytokinesis.
AB - Hetero- and homodimerization of 14-3-3 proteins demonstrate distinctive functions in mammals and plants. Trypanosoma brucei 14-3-3I and II (Tb14-3-3I and II) play pivotal roles in motility, cytokinesis and the cell cycle; however, the significance and the mechanism of Tb14-3-3 dimerization are remained to be elucidated. We found that ectopically expressed epitope-tagged Tb14-3-3I and II proteins formed hetero- and homodimers with endogenous Tb14-3-3I and II proteins. However, we also found the ability to form hetero- or homodimers between Tb14-3-3I and II proteins was clearly affected by the sequence and location of the epitope tag used. We found a blue native polyacrylamide gel electrophoresis system followed by western blotting may distinguish monomer from dimer structure, and stable from unstable conformation of Tb14-3-3. Combined with co-immunoprecipitation results, we revealed that Tb14-3-3 proteins mainly existed as heterodimeric form. Furthermore, co-overexpression of Tb14-3-3I and II proteins in T. brucei induced aberrant numbers of organelles in cells, but overexpression of either isoform alone rarely produced such morphology. These results suggest that heterodimers play more significant roles than homodimers not only in the maintenance of steady-state levels of the 14-3-3 proteins but also in the regulation of cytokinesis.
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U2 - 10.1093/jb/mvt016
DO - 10.1093/jb/mvt016
M3 - Article
C2 - 23457405
AN - SCOPUS:84877278778
VL - 153
SP - 431
EP - 439
JO - Journal of Biochemistry
JF - Journal of Biochemistry
SN - 0021-924X
IS - 5
ER -