Document Detail

Evidence supporting the role of a proteinaceous, loosely bound extracellular molecule in the cell density signaling between tendon cells.
MedLine Citation:
PMID:  1483965     Owner:  NLM     Status:  MEDLINE    
Normal cells in culture respond to cell density by altering their proliferation rates and their pattern of protein expression. Primary avian tendon (PAT) cells are a case in point where procollagen production increases approximately 10-fold at high cell density while proliferation almost ceases. In an earlier report focusing on the cell density regulation of procollagen expression, the signaling mechanism communicating the presence of other cells was shown to have the characteristics of a loosely bound component of the cell layer. Extending these studies to the cell density regulation of proliferation, the cell density signal (CDS) was again shown to be altered by medium agitation, stimulating cell division. Agitation, however, was only disruptive to cell signaling when there was a high ratio of medium to cells. When sufficient cells were present, agitation was less effective. Therefore, the CDS controlling procollagen production and the CDS controlling the inhibition of growth seemed to be linked because the signaling mechanism is disrupted in a parallel manner by agitation. However, the proliferative response of PAT cells is more complex in that there is also a positive influence at moderate cell density (> 2 x 10(4) cells/cm2) on the rate of cell division. As a consequence, PAT cells would not proliferate into an area of low cell density, but within the same dish would rapidly fill an area of moderate density. PAT cells were capable of filling a gap between high cell density areas if the gap was less than 2 mm. Medium agitation also affected cells at low cell density in a different manner. It was inhibitory if all the cells were at low cell density but it was stimulatory if the cells at low cell density were in close proximity to cells at high cell density. In addition, medium conditioned by agitation over cells at a high cell density would stimulate cells at low cell density to divide and grow out into low cell density regions. Using the growth-promoting activity of the conditioned medium as an assay, this component of the CDS was shown to have unique characteristics: heat, pH, dithiothreitol (DTT) stable; tris ion and protease sensitive. By gel exclusion chromatography it was larger than 100 kDa. But after DTT treatment its mobility shifted to < 30 kDa while retaining activity.
J R Zayas; R I Schwarz
Related Documents :
19197295 - Connexin-related signaling in cell death: to live or let die?
16099865 - Characterization of a novel rat epididymal cell line to study epididymal function.
10666075 - Electrical interactions between a real ventricular cell and an anisotropic two-dimensio...
97855 - Alterations of intercellular junctions in acinic cell carcinoma of the canine pancreas.
20924205 - Proinflammatory/profibrotic effects of interleukin-17a on human proximal tubule epithel...
23921815 - Bile acid at low ph reduces squamous differentiation and activates egfr signaling in es...
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  In vitro cellular & developmental biology : journal of the Tissue Culture Association     Volume:  28A     ISSN:  0883-8364     ISO Abbreviation:  In Vitro Cell. Dev. Biol.     Publication Date:    1992 Nov-Dec
Date Detail:
Created Date:  1993-02-16     Completed Date:  1993-02-16     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  8506951     Medline TA:  In Vitro Cell Dev Biol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  745-54     Citation Subset:  IM    
Cell and Molecular Biology Division, Lawrence Berkeley Laboratory, University of California, Berkeley 94720.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cell Communication / physiology
Cell Count / drug effects
Cell Division / drug effects,  physiology
Cells, Cultured
Chick Embryo
Chromatography, Gel
Culture Media, Conditioned / pharmacology
Dithiothreitol / pharmacology
Extracellular Matrix Proteins / physiology*
Hot Temperature
Hydrogen-Ion Concentration
Procollagen / metabolism
Signal Transduction / physiology*
Tendons / cytology*,  metabolism
Reg. No./Substance:
0/Culture Media, Conditioned; 0/Extracellular Matrix Proteins; 0/Procollagen; 3483-12-3/Dithiothreitol

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

Previous Document:  Relative promoter activity in human mammary epithelial cells assayed by transient expression.
Next Document:  Participation of the mitochondrial genome in the differentiation of neuroblastoma cells.