Activin/Nodal signalling in stem cells.

Activin/Nodal growth factors control a broad range of biological processes, including early cell fate decisions, organogenesis and adult tissue homeostasis. Here, we provide an overview of the mechanisms by which the Activin/Nodal signalling pathway governs stem cell function in these different stages of development. We describe recent findings that associate Activin/Nodal signalling to pathological conditions, focusing on cancer stem cells in tumorigenesis and its potential as a target for therapies. Moreover, we will discuss future directions and questions that currently remain unanswered on the role of Activin/Nodal signalling in stem cell self-renewal, differentiation and proliferation.S.P. was supported by the EUFP7 grant InnovaLIV and an FEBS long-term fellowship. L.V. was supported by the ERC starting grant Relieve IMDs and the Cambridge Hospitals National Institute for Health Research Biomedical Research Centre.This is the accepted manuscript of a paper published in Development (Pauklin S, Vallier L, Development 2015, 142, 607-619, doi: 10.1242/dev.091769). The final version is available at http://dx.doi.org/10.1242/dev.09176