Time-lapse imaging reveals dynamic relocalization of PP1gamma throughout the mammalian cell cycle
- PMID: 12529430
- PMCID: PMC140231
- DOI: 10.1091/mbc.e02-07-0376
Time-lapse imaging reveals dynamic relocalization of PP1gamma throughout the mammalian cell cycle
Abstract
Protein phosphatase 1 (PP1) is a ubiquitous serine/threonine phosphatase that regulates many cellular processes, including cell division. When transiently expressed as fluorescent protein (FP) fusions, the three PP1 isoforms, alpha, beta/delta, and gamma1, are active phosphatases with distinct localization patterns. We report here the establishment and characterization of HeLa cell lines stably expressing either FP-PP1gamma or FP alone. Time-lapse imaging reveals dynamic targeting of FP-PP1gamma to specific sites throughout the cell cycle, contrasting with the diffuse pattern observed for FP alone. FP-PP1gamma shows a nucleolar accumulation during interphase. On entry into mitosis, it localizes initially at kinetochores, where it exchanges rapidly with the diffuse cytoplasmic pool. A dramatic relocalization of PP1 to the chromosome-containing regions occurs at the transition from early to late anaphase, and by telophase FP-PP1gamma also accumulates at the cleavage furrow and midbody. The changing spatio-temporal distribution of PP1gamma revealed using the stable PP1 cell lines implicates it in multiple processes, including nucleolar function, the regulation of chromosome segregation and cytokinesis.
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References
-
- Andersen JS, Lyon CE, Fox AH, Leung AK, Lam YW, Steen H, Mann M, Lamond AI. Directed proteomic analysis of the human nucleolus. Curr Biol. 2002;12:1–11. - PubMed
-
- Barker HM, Brewis ND, Street AJ, Spurr NK, Cohen PT. Three genes for protein phosphatase 1 map to different human chromosomes: sequence, expression and gene localization of protein serine/threonine phosphatase 1 beta (PPP1CB) Biochim Biophys Acta. 1994;1220:212–218. - PubMed
-
- Barker HM, Craig SP, Spurr NK, Cohen PT. Sequence of human protein serine/threonine phosphatase 1 gamma and localization of the gene (PPP1CC) encoding it to chromosome bands 12q24.1-q24.2. Biochim Biophys Acta. 1993;1178:228–233. - PubMed
-
- Berndt N, Dohadwala M, Liu CW. Constitutively active protein phosphatase 1alpha causes Rb-dependent G1 arrest in human cancer cells. Curr Biol. 1997;7:375–386. - PubMed
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