title: Cell-cycle-related variation in proteins in suspension-cultured rice cells.
abstract: To understand the cell cycle process in plants, we searched for proteins that quantitatively change during the cell cycle in suspension-cultured rice ( Oryza sativa L.) cells. The proteins were analyzed by a two-dimensional polyacrylamide gel electrophoresis image-analysis system. We detected 11 proteins that quantitatively changed during the cell cycle, among which beta-tubulins and a calreticulin-like protein were identified. The amounts of beta-tubulin proteins were low in the M phase and high in the G1 phase. In contrast, mRNAs for two of the three types of beta-tubulin were high in the M phase of the cell cycle. The addition of protease inhibitors MG132 or E64d to the cells decreased the beta-tubulin proteins during 24 h, suggesting that beta-tubulin proteins are degraded in vivo by proteases other than those whose activities are inhibited by MG132 or E64d.
authors.affiliation: Department of Bioproduction Science, Faculty of Horticulture, Chiba University, Matsudo, Chiba 271-8510, Japan.
authors.forename: Tomomasa
authors.initials: T
authors.lastname: Takase
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yanagawa
authors.forename: Setsuko
authors.initials: S
authors.lastname: Komatsu
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Junji
authors.initials: J
authors.lastname: Hashimoto
mesh_terms: D000595:Amino Acid Sequence; D002453:Cell Cycle / Q000502:physiology*; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D015180:Electrophoresis, Gel, Two-Dimensional; D007700:Kinetics; D012275:Oryza / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry; D010940:Plant Proteins / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D010446:Peptide Fragments; D010940:Plant Proteins; D003513:Cycloheximide