Document Detail


Megakaryocyte polyploidization is associated with decreased expression of polo-like kinase (PLK).
MedLine Citation:
PMID:  16805859     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: During differentiation, megakaryocytes (MK), the bone marrow precursors of circulating blood platelets, undergo polyploidization, repeated rounds of DNA replication without cell division. Mature normal MK may contain a DNA content of up to 128N, in contrast to normal diploid (2N) cells. The extent of polyploidy may influence the number of platelets produced by the MK. Therefore, understanding the molecular mechanisms regulating polyploidization could identify events involved in controlling both cell division and thrombopoiesis.
OBJECTIVE: We investigated the expression of several proteins involved in mitosis in cultured mouse MK, and tested the effect of expression on polyploidization.
METHODS: Western blot and immunofluorescent analyses were used to assess expression of cell cycle proteins in cultured MK. Populations of polyploidizing MK were separated on the basis of DNA content by flow cytometry. The gene encoding mouse polo-like kinase 1 (PLK-1) was introduced into MK by retroviral transduction, and its effects measured by flow cytometry.
RESULTS: Polyploid mouse MK expressed lower levels of two proteins, p55CDC and PLK-1, whose activity is necessary for cell cycle progression and completion of mitosis. Comparison of sorted 2N/4N and polyploid MK indicated that PLK-1 expression was absent in polyploid MK, while expression of other cell cycle proteins was similar in both populations. Forced expression of PLK-1 during MK differentiation was associated with decreased polyploidization.
CONCLUSION: These experiments suggest that PLK-1 is an important regulator of polyploidization in differentiating MK.
Authors:
M Yagi; G J Roth
Related Documents :
16213209 - Right place, right time, and only once: replication initiation in metazoans.
12072179 - Investigating the relationship between the cell cycle and apoptosis using flow cytometry.
17877709 - The cell cycle of sulfolobus.
11731319 - Cell cycle control of cell morphogenesis in caulobacter.
12934019 - Expression deconvolution: a reinterpretation of dna microarray data reveals dynamic cha...
12470209 - Modulating cell cycle: current applications and prospects for future drug development.
8270479 - Satellite cell content in muscles of large and small mice.
9440139 - Adverse effects of reverse triiodothyronine on cellular metabolism as assessed by 1h an...
11310849 - Adenoviral gene delivery can inactivate kupffer cells: role of oxidants in nf-kappab ac...
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.     Date:  2006-06-20
Journal Detail:
Title:  Journal of thrombosis and haemostasis : JTH     Volume:  4     ISSN:  1538-7933     ISO Abbreviation:  J. Thromb. Haemost.     Publication Date:  2006 Sep 
Date Detail:
Created Date:  2006-09-11     Completed Date:  2006-11-29     Revised Date:  2011-11-02    
Medline Journal Info:
Nlm Unique ID:  101170508     Medline TA:  J Thromb Haemost     Country:  England    
Other Details:
Languages:  eng     Pagination:  2028-34     Citation Subset:  IM    
Affiliation:
Research, Seattle Division, Veterans Affairs Puget Sound Health Care System, WA 98108, USA. myagi@u.washington.edu
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Cell Cycle Proteins / analysis,  genetics*,  physiology*
Cell Differentiation
Cells, Cultured
Down-Regulation / genetics
Flow Cytometry
Gene Expression Regulation / physiology*
Megakaryocytes / cytology*
Mice
Mitosis / genetics
Polyploidy*
Protein-Serine-Threonine Kinases / genetics*,  physiology*
Proto-Oncogene Proteins / genetics*,  physiology*
Thrombopoiesis / genetics
Transduction, Genetic
Grant Support
ID/Acronym/Agency:
HL39947/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Cdc20 protein, mouse; 0/Cell Cycle Proteins; 0/Proto-Oncogene Proteins; EC 2.7.11.1/Protein-Serine-Threonine Kinases; EC 2.7.11.1/polo-like kinase 1

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Age-specific hormonal decline is accompanied by transcriptional changes in human sebocytes in vitro.
Next Document:  von Willebrand factor A1 domain can adequately substitute for A3 domain in recruitment of flowing pl...