Analysis of an expression profile of genes in the human adipose tissue

Increasing evidence suggests that in addition to storing excess energy as fat, adipose tissue acts as an endocrine organ secreting various factors into the blood stream. Every time a new factor is found in adipose tissue, however, its implication is discussed independently, and a systematic analyses based upon a global view of gene expression of this tissue has not been performed. To describe the function of this tissue in terms of gene expression, and to find new factors, we performed random complementary DNA (cDNA) sequencing using a 3'-directed cDNA library that faithfully represents the composition of the messenger RNA (mRNA). Various well-known but unexpected genes, including those for gelsolin, plasma glutathione peroxidase (GPX-3) and carboxypeptidase E (CPE) were shown to be very active. By comparing the expression profile of active genes in the adipose with those of other tissues and with data in dbEST, we identified seven new genes that are specifically expressed in adipose tissue. Among these, one encoded a protein with collagen-like repeats and a putative secretion signal. These data can be used as new tools for analyses of the physiology of this tissue, as well as the etiology and complications of obesity.