Type XVIII collagen is newly transcribed during bovine adipogenesis

To isolate candidate genes concerned with bovine adipocyte differentiation, we have constructed a subtraction cDNA library from a clonal bovine intramuscular preadipocyte (BIP) cell line. We have isolated a set of cDNA clones whose respective mRNA levels are upregulated during the differentiation of BIP cells. The sequence of one subtracted cDNA fragment was highly homologous to that of mouse type XVIII collagen. Northern blot analysis and reverse transcriptase polymerase chain reaction (RT-PCR) showed that collagen XVIII gene expression increased during adipocyte differentiation. The collagen XVIII gene was also highly expressed in fat tissue. Although its function is unclear, these expression patterns indicate that type XVIII collagen may be associated with adipocyte differentiation in cattle.