In a blog published earlier today I wrote about PHA-4 and SKN-1 which extend survival after dietary restriction in these roundworms. These two proteins are transcription factors, which regulate the expression of many genes. They may also trigger hormones that coordinate physiological responses to dietary restriction.
The PHA-4 protein, was originally described for its role in the development of the pharynx in worm embryos, and is a member of the forkhead family of transcription factors, and is very similar to mammalian FOXA proteins. In mammals, FOXA proteins have developmental roles, and regulate glucose metabolism later in life. The requirement for PHA-4 is very specific.
In a paper by JiHun Kim et al they mention that increased phosphorylation of FOXO1A, a FOXO transcription factor, has been implicated in several human They show that in gastric carcinomas, the expression of pFOXO1A was observed in 84.6% of 272 cases examined, The expression of pFOXO1A is a frequent and early event in gastric tumorigenesis and that there is a significant correlation between pFOXO1A and better prognosis.
Diet induced longevity and gastric cancer, association or fluke?
Ji Hun Kim et al , 2007, Constitutive phosphorylation of the FOXO1A transcription factor as a prognostic variable in gastric cancer. Modern Pathology (2007) 20, 835–842;
- Martin Eastwood