Restoration of cell-to-cell communication in thyroid cell lines by transfection with and stable expression of the connexin-32 gene. Impact on cell proliferation and tissue-specific gene expression.
J Biol Chem
; 272(39): 24710-6, 1997 Sep 26.
Article
in En
| MEDLINE
| ID: mdl-9305943
ABSTRACT
Normal thyroid epithelial cells coexpress connexin-32 and connexin-43, which form distinct gap junctions. In primary culture, connexin-43 is expressed by thyrocytes in monolayers or reorganized into follicles, whereas the expression of connexin-32 is dependent upon the reconstitution of follicles. To study the functional impact of connexin-32 gap junctions in thyroid cells, we transfected connexin-32 cDNA in two thyroid-derived communication-deficient cell lines, FRT and FRTL-5. The selected clones, which stably expressed connexin-32 at high levels and exhibited high gap junction-mediated dye-coupling, presented a reduced proliferation rate as compared with that of the corresponding wild-type FRT and FRTL-5 cells; the mean population doubling time was increased by approximately 35%. The proliferation of connexin-32-transfected FRTL-5 cells remained thyrotropin-dependent; the range of thyrotropin concentrations that stimulated growth was the same in transfected and control cells. The expression of connexin-32 led to an increase of thyroglobulin gene expression in FRTL-5 cells. The expression of two other tissue-specific proteins, thyroid transcription factor-1 and Pax-8, was unchanged. These findings provide evidence that connexin-32 gap junction-mediated cell-to-cell communication participates in the control of growth and differentiation of thyroid cells.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Thyroid Gland
/
Cell Communication
/
Gene Expression Regulation
/
Connexins
Limits:
Animals
Language:
En
Journal:
J Biol Chem
Year:
1997
Document type:
Article
Affiliation country:
Francia