A study appearing in Diabetes shows that excessive expression of a protein called inhibitor of differentiation 1 (Id1) seems to increase the risk of obesity and possibly obesity-related diseases. The study is carried out by Augusta University researchers.
Id1 is a member of the basic HLH family of transcription factors. This protein is known to promote proliferation and inhibit differentiation. Upregulation of Id1 expression has been found in a variety of cancers, such as prostate cancer, glioblastoma, and non-small cell lung cancer.
The new study reveals a new function of Id1: Excessive Id1 reduces fat burning ability of brown fat. Discovery of Id1 as a regulator of brown fat metabolism may open an avenue for therapeutic intervention for obesity and diabetes.
In the work, the team created mice that expressed high levels of Id1 in the fat cells. These mice gained much more weight than the control mice, no matter both groups of mice were on a high-fat diet or on a normal diet. Further investigation demonstrated that the protein Id1 directly binds to and suppresses the activity of PGC1α, a transcriptional coactivator involved in regulation of energy metabolism, and therefore reduces brown fat’s burning ability.
Fat, or adipose tissue, is a kind of body tissue that helps store energy and serves as a source of energy. There are two major types of fat -- brown and white. Brown fat helps turn food into body heat, so it is also referred to as “good” fat. White fat, or called “bad” fat, stores energy from food and makes people fatter.
The finding that the Id1 protein inhibits brown fat's burning ability explains why mice with high Id1 levels were more likely to develop obesity. It is well established that obesity is a risk factor of many health problems, including diabetes, heart disease, and high blood pressure. The study “has significant implications in the treatment of obesity and its associated diseases such as diabetes.” (Cusabio provides proteins and antibodies. http://www.cusabio.c...talog-20-1.html)