Upregulation of DNA repair genes and cell extrusion underpin the remarkable radiation resistance of < i > Trichoplax adhaerens < /i >

by Angelo Fortunato, Alexis Fleming, Athena Aktipis, Carlo C. MaleyTrichoplax adhaerens is the simplest multicellular animal with tissue differentiation and somatic cell turnover. Like all other multicellular organisms, it should be vulnerable to cancer, yet there have been no reports of cancer inT.adhaerens or any other placozoan. We investigated the cancer resistance ofT.adhaerens, discovering that they are able to tolerate high levels of radiation damage (218.6 Gy). To investigate howT.adhaerens survive levels of radiation that are lethal to other animals, we examined gene expression after the X-ray exposure, finding overexpression of genes involved in DNA repair and apoptosis including theMDM2 gene. We also discovered thatT.adhaerens extrudes clusters of inviable cells after X-ray exposure.T.adhaerens is a valuable model organism for studying the molecular, genetic, and tissue-level mechanisms underlying cancer suppression.
Source: PLoS Biology: Archived Table of Contents - Category: Biology Authors: Source Type: research