Expression of type XVI collagen in cultured skin fibroblasts is related to cell growth arrest

AbstractThe expression of type XVI collagen in various phases of cell growth in cultured skin fibroblasts was studied. A marked increase in type XVI collagen mRNA level was found in stationary phases of cell growth (non-adherent and confluent phases), whereas the expression of type I and III collagens was undetectable in the non-adherent phase but became greater in the confluent phase. When suspended cells were further cultured over 72 h (suspension arrest), mRNA level and gene transcription of type XVI collagen were time-dependently increased whereas those of type I collagen remained undetectable. When the confluent cells were further cultured for 72 h under the condition of serum deprivation (serum deprivation arrest), mRNA levels of both type XVI collagen and type I collagen were elevated. The level of type XVI collagen polypeptide in the culture media of suspension-arrested and serum deprivation-arrested cells paralleled the mRNA level of type XVI collagen. The results indicate that expression of type XVI collagen (a member of the fibril-associated collagens with interrupted triple helices), unlike interstitial collagens (type I collagen), is related to cell growth arrest brought about by two different growth inhibiting systems, suspension arrest and serum deprivation arrest