Competitiveness for the niche and mutual dependence of the germline and somatic stem cells in the Drosophila testis are regulated by the JAK/STAT signaling.
In many tissues, two or more types of stem cells share a niche, and how the stem cells coordinate their self-renewal and differentiation is poorly understood. In the Drosophila testis, germ line stem cells (GSCs) and somatic cyst progenitor cells (CPCs) contact each other and share a niche (the hub). The hub expresses a growth factor unpaired (Upd) that activates the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway in GSCs to regulate the stem cell self-renewal. Here, we demonstrate that the JAK/STAT signaling also regulates CPCs self-renewal. We also show that a negative regulator, the suppressor of cytokine signaling 36E (SOCS36E), suppresses JAK/STAT signaling in somatic cells, preventing them from out-competing the GSCs. Furthermore, through selectively manipulating the JAK/STAT signaling level in either CPCs or GSCs, we demonstrate that the somatic JAK/STAT signaling is essential for self-renewal and maintenance of both CPCs and GSCs. These data suggest that a single JAK/STAT signal from the niche orchestrate the competitive and dependent co-existence of GSCs and CPCs in the Drosophila testis niche.
Singh
Shree Ram
SR
Mouse Cancer Genetics Program, National Institutes of Health, National Cancer Institute at Frederick, Frederick, Maryland 21702, USA. singhshr@mail.nih.gov
Zheng
Zhiyu
Z
Wang
Hong
H
Oh
Su-Wan
SW
Chen
Xiu
X
Hou
Steven X
SX
D000818:Animals; D002450:Cell Communication / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D005854:Germ Cells / Q000166:cytology / Q000378:metabolism*; D018095:Germ-Line Mutation / Q000235:genetics; D053612:Janus Kinases / Q000235:genetics / Q000378:metabolism*; D008297:Male; D050791:STAT Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D013091:Spermatogenesis / Q000502:physiology; D055153:Stem Cell Niche / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D050826:Suppressor of Cytokine Signaling Proteins / Q000235:genetics / Q000378:metabolism; D013737:Testis / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D029721:Drosophila Proteins; D050791:STAT Transcription Factors; C460659:Socs36E protein, Drosophila; D050826:Suppressor of Cytokine Signaling Proteins; D014157:Transcription Factors; D053612:Janus Kinases; C085845:hop protein, Drosophila