Stem cell niche is a specialized microenvironment crucial for stem cell self-renewal. Drosophila testis contains germline stem cells (GSCs) and somatic cyst stem cells (CySCs), providing a good model for studying niche-stem cell interaction. Recently, researchers from Chinese Academy of Sciences reveal that Hedgehog (Hh) signaling plays dual roles in the regulation of CySCs and GSCs in Drosophila testis.
Previous studies in Drosophila testis reveal that GSCs and CySCs share the same niche which multiple signaling pathways are involved. BMP signaling regulates the self-renewal of GSCs and JAK-STAT signaling is critical for CySCs maintenance. How different types of stem cells are regulated in this niche is still poorly understood.
In this study, Dr. ZHAO Yun, Dr. ZHANG Lei and their research teams at Shanghai Institute of Biochemistry and Cell Biology, CAS presented evidence that Hh signaling is primarily received by CySCs to regulate its self-renewal, which is in parallel with JAK-STAT signaling. Hh signaling in CySCs has a secondary effect on GSCs through influencing BMP signaling in GSCs. Thus, Hh signaling plays dual roles to maintain the homeostasis of testis niche.
This work entitled "Dual roles of Hh signaling in the regulation of somatic stem cell self-renewal and germline stem cell maintenance in Drosophila testis" was published online before print in Cell Research on February, 2013.
This work was supported by research grants from Ministry of Science and Technology of China, National Natural Science Foundation of China, and Chinese Academy of Sciences.
A schematic model showing that Hh signaling coordinates with JAK-STAT and BMP signaling to maintain the homeostasis of testis niche.
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