A paper published in the December 1st issue of Genes & Development reveals a novel role for the p53 tumor suppressor pathway in organogenesis during embryonic development. Dr. Jinrong Peng and colleagues show that the zebrafish Def protein is an organ-specific factor that represses expression of a newly identified p53 isoform to coordinate digestive organ growth. def-mutant zebrafish display hypomorphic digestive organs that result from defects in organ expansion and maturation.
Further analysis demonstrated that the increased expression of the delta113 p53 isoform in def-mutant digestive organs leads to cell cycle arrest and reduced organ growth.
Dr. Peng explains that "based on all data obtained in our hands thus far, we believe the increase in p53 ispform in the def mutant contributes significantly (but not fully) to cause the hypoplasia digestive organs.