Distinct functions of three Wnt proteins control mirror-symmetric organogenesis in the C. elegans gonad
Abstract
Organogenesis requires the proper production of diverse cell types and their positioning/migration. However, the coordination of these processes during development remains poorly understood. The gonad in C. elegans exhibits a mirror-symmetric structure guided by the migration of distal tip cells (DTCs), which result from asymmetric divisions of somatic gonadal precursors (SGPs; Z1 and Z4). We found that the polarity of Z1 and Z4, which possess mirror-symmetric orientation, is controlled by the redundant functions of the LIN-17/Frizzled receptor and three Wnt proteins (CWN-1, CWN-2, and EGL-20) with distinct functions. In lin-17 mutants, CWN-2 promotes normal polarity in both Z1 and Z4, while CWN-1 promotes reverse and normal polarity in Z1 and Z4, respectively. In contrast, EGL-20 inhibits the polarization of both Z1 and Z4. In lin-17 egl-20 cwn-2 triple mutants with a polarity reversal of Z1, DTCs from Z1 frequently miss-migrate to the posterior side. Our further analysis demonstrates that the mis-positioning of DTCs in the gonad due to the polarity reversal of Z1 leads to mis-migration. Similar mis-migration was also observed in cki-1(RNAi) animals producing ectopic DTCs. These results highlight the role of Wnt signaling in coordinating the production and migration of DTCs to establish a mirror-symmetric organ.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files; source data files have been provided for Figures 3 and 4.
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Funding
Japan Society for the Promotion of Science (JP16H04797)
- Hitoshi Sawa
Takeda Science Foundation
- Hitoshi Sawa
NIG-JOINT (88A2024)
- Shuhei So
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2024, So et al.
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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