Open AccessDirect control of somatic stem cell proliferation factors by theDrosophilatestis stem cell niche
Author(s) -
Eugene Albert,
Olga A. Puretskaia,
Nadezhda V. Terekhanova,
Anastasia Labudina,
Christian Bökel
Publication year - 2018
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.754
H-Index - 325
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.156315
Subject(s) - biology , stem cell , niche , microbiology and biotechnology , hedgehog , somatic cell , regulator , cell fate determination , stem cell niche , hippo signaling pathway , signalling , signal transduction , transcription factor , genetics , progenitor cell , gene , ecology
Niches have traditionally been characterized as signalling microenvironments that allow stem cells to maintain their fate. This definition implicitly assumes that the various niche signals are integrated towards a binary fate decision between stemness and differentiation. However, observations in multiple systems have demonstrated that stem cell properties such as proliferation and self renewal can be uncoupled at the level of niche signalling input, which is incompatible with this simplified view. We have studied the role of the transcriptional regulator Zfh1, a shared target of the Hedgehog and Jak/Stat niche signalling pathways, in the somatic stem cells of the Drosophila testis. We found that Zfh1 binds and downregulates salvador and kibra, two tumour suppressor genes of the Hippo/Wts/Yki pathway, thereby restricting Yki activation and proliferation to the Zfh1 positive stem cells. These observations provide an unbroken link from niche signal input to an individual aspect of stem cell behaviour that does not, at any step, involve a fate decision. We discuss the relevance of these findings for an overall concept of stemness and niche function.