The Gα GOA-1/GNAO1 non-autonomously promotes germline stem cell quiescence in feminized C. elegans hermaphrodites from the gonadal sheath cells.

Stem cell proliferation rates must be precisely regulated as insufficient proliferation leads to tissue loss, whereas excessive proliferation causes tumorigenesis and cancer. A homeostatic balance is therefore achieved through feedback loops that adjust stem/progenitor cell proliferation rates to match the demand for their differentiated progeny. While such a homeostatic feedback mechanism adjusts germline stem cell (GSC) proliferation rates to oocyte needs in the Caenorhabditis elegans adult hermaphrodite germline, its inner workings are incompletely understood. Here we show that the Gα GOA-1 /GNAO1 is required specifically in the gonadal sheath cells to non-autonomously promote GSC quiescence in spermless hermaphrodites. Given that dysregulation of G protein signalling is frequently observed in human cancers, Gα dependent homeostatic control of stem cell proliferation may represent a conserved tumour suppressive mechanism.