Regulation of collagen synthesis in fibroblasts within a three-dimensional collagen gel.
Fibroblasts cultivated within a three-dimensional collagen gel display an elongated, spindle-like morphology, reduce their proliferation rate, contact the gel to a very dense tissue, and modify their metabolic activity as compared to monolayer cultures. Collagen synthesis measured as protein-bound hydroxyproline is reduced to 5% of the values found in monolayer culture. The reduction involving type I and type III collagen is due to decreased de novo synthesis and not to enhanced degradation. Dot blot hybridization, Northern blot analysis, and in situ hybridization using collagen I- and III-specific cDNA probes demonstrate that reduced biosynthesis rates are reflected by a marked reduction of pro alpha 1 (I), pro alpha 2 (I), and pro alpha 1 (III) collagen mRNA indicating pretranslational regulation. A similar reduction was observed for actin mRNA whereas levels of tubulin mRNA were similar for fibroblasts in monolayer culture or cultivated within the three-dimensional collagen gels. The data suggest a specific reprogramming of various cellular activities in response to contact with the reconstituted extracellular matrix.
Mauch
C
C
Dermatologische Klinik der Ludwig Maximilians Universität, München 2, Federal Republic of Germany.
Hatamochi
A
A
Scharffetter
K
K
Krieg
T
T
D015152:Blotting, Northern; D002455:Cell Division; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis* / Q000235:genetics; D003720:Densitometry; D004591:Electrophoresis, Polyacrylamide Gel; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D009693:Nucleic Acid Hybridization; D011347:Procollagen / Q000235:genetics / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000032:analysis; D014158:Transcription, Genetic
D011347:Procollagen; D012333:RNA, Messenger; D003094:Collagen