Rapid accumulation of nucleostemin in nucleolus during newt regeneration.
In newt regeneration, differentiated cells can revert to stem cell-like cells in which the proliferative ability and multipotentiality are restored after dedifferentiation. However, the molecular events that occur during the dedifferentiation still remain obscure. Nucleostemin has been identified in mammals as a nucleolar protein specific to stem cells and cancer cells. In this study, a newt nucleostemin homologue was cloned and its regulation was analyzed. During lens regeneration, the expression of nucleostemin was activated and nucleostemin rapidly accumulated in the nucleoli of dedifferentiating pigmented epithelial cells 2 days before cell cycle reentry. During limb regeneration, nucleostemin also accumulated in the nucleoli of degenerating multinucleate muscle fibers before blastema formation. These findings suggest that nucleostemin plays a role in the dedifferentiation of newt cells and can provide crucial clues for addressing the molecular events at early steps of cellular dedifferentiation in newts.
Maki
Nobuyasu
N
Center for Developmental Biology, RIKEN Kobe, Chuo-ku, Kobe, Japan. nmaki@cdb.riken.jp
Takechi
Katsuaki
K
Sano
Shozo
S
Tarui
Hiroshi
H
Sasai
Yoshiki
Y
Agata
Kiyokazu
K
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D004625:Embryo, Nonmammalian; D005260:Female; D019204:GTP-Binding Proteins; D005786:Gene Expression Regulation; D007498:Iris / Q000502:physiology; D008969:Molecular Sequence Data; D018485:Muscle Fibers, Skeletal / Q000166:cytology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D016601:RNA-Binding Proteins; D012038:Regeneration / Q000235:genetics*; D012455:Salamandridae / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D017386:Sequence Homology, Amino Acid
D002352:Carrier Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; C470311:nucleostemin protein, mouse; D019204:GTP-Binding Proteins