University of Dundee

Insights into "Parma Ham" mice

28 Jun 2016

Similar to Italian Heavy pigs, 'Parma Ham' mice grow long bones, have high muscle mass and put on fat as they age. Research recently published in PNAS has provided insights into the reasons for this.

Shuai Chen studied these mice in the lab of Carol MacKintosh in Life Sciences - University of Dundee, and he and his wife Hong-Yu continued the investigations when they set up their own labs in Nanjing University. They uncovered a facinating mechanism that links whole body nutrient status with growth. Essentially, low energy reserves activate an energy gauge named AMPK in the liver, which in turn phosphorylates a protein called TBC1D1 and inhibits the release of the hormone insulin-like growth factor 1 (IGF1).

In the Parma Ham mice, TBC1D1 is mutated so that it cannot be phosphorylated by AMPK. This means that secretion of IGF1 is higher than normal, and IGF1 promotes growth of various tissues and enhances fat production in adipose tissue. These molecular explanations for the Parma Ham phenotype have implications for understanding and treating obesity, and metabolic and growth syndromes. Interestingly, TBC1D1 mutations have been linked to a female obesity syndrome in humans and to heaviness in certain farm animals.

Full article can be viewed here