Scientists discover how immune cells determine identity
Findings by a team from the NIH's National Institute of Arthritis and Musculoskeletal and Skin Diseases led by John O'Shea may lead to the identification of new therapeutic targets for treating disorders related to the immune system.
While there are 3.2 billion DNA base pairs in the human genome, approximately two percent are in regions thought of as genes, which provide the code for proteins. Until recently, the role of the other 98 percent of the genome was not well known.
O'Shea's team used whole genome DNA sequencing technology to allow the team to see which parts of the genomic DNA is involved actively in the support of various cellular functions. The researchers found that the members of the signal transducers and activators of transcription protein family shape the identity of T helper cells in the immune system.
The scientists found a greater than expected impact by the STAT proteins' regulation of enhancer activity. Enhancers are short DNA regions that regulate gene transcription from outside the genes. Enhancers do not code for proteins directly, but they regulate the process of protein production.
O'Shea's team determined that STAT proteins work as cellular environmental sensors that regulate the enhancers from the junk region of the genome to determine the subtype of a T cell.
Further research may tell scientists how the STAT proteins and the enhancers relate to the genetic risk of immune diseases.