Cytonemes coordinate asymmetric signaling and organization in the Drosophila muscle progenitor niche

• Published in: Nature communications Vol. 13; no. 1; p. 1185
• Main Authors: Patel, Akshay, Wu, Yicong, Han, Xiaofei, Su, Yijun, Maugel, Tim, Shroff, Hari, Roy, Sougata
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group UK 04.03.2022; Nature Portfolio
• Subjects: Animals; Drosophila - metabolism; Drosophila melanogaster - metabolism; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Fibroblast Growth Factors - metabolism; Muscles - metabolism
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-28587-z

Asymmetric signaling and organization in the stem-cell niche determine stem-cell fates. Here, we investigate the basis of asymmetric signaling and stem-cell organization using the Drosophila wing-disc that creates an adult muscle progenitor (AMP) niche. We show that AMPs extend polarized cytonemes to contact the disc epithelial junctions and adhere themselves to the disc/niche. Niche-adhering cytonemes localize FGF-receptor to selectively adhere to the FGF-producing disc and receive FGFs in a contact-dependent manner. Activation of FGF signaling in AMPs, in turn, reinforces disc-specific cytoneme polarity/adhesion, which maintains their disc-proximal positions. Loss of cytoneme-mediated adhesion promotes AMPs to lose niche occupancy and FGF signaling, occupy a disc-distal position, and acquire morphological hallmarks of differentiation. Niche-specific AMP organization and diversification patterns are determined by localized expression and presentation patterns of two different FGFs in the wing-disc and their polarized target-specific distribution through niche-adhering cytonemes. Thus, cytonemes are essential for asymmetric signaling and niche-specific AMP organization.