FAM3B or PANDER (PANcreatic DERived factor) has been identifed as a regulator of glucose homeostasis and beta cell function. The protein is expressed in the endocrine pancreas and co-secreted with insulin in response to glucose, particularly under conditions of insulin resistance. The protein had initially been predicted to be a member of the four-helical cytokine family, hence the FAM3B designation. PANDER induces apoptosis of insulin-secreting beta-cells when over-expressed in vitro. It has been associated with the progression of type 2 diabetes by downregulating beta cell function as well as insulin sensitivity in the liver.
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