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bioRxiv · 10.1101/2023.03.28.534640

Ribosomal protein mutation suppresses gonadal leader cell migration defects in mig-17/ADAMTS mutants in Caenorhabditis elegans

Nishiwaki, K.·Kim, H.-S.·Mitsuzumi, K.·Kondo, S.·Yamaoka, R.·Ihara, S.·Otsuka, H.·Kubota, Y.·Fujiwara, T.·Shibata, Y.
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Abstract

The migration of the gonadal distal tip cells (DTCs) in Caenorhabditis elegans provides an excellent model for studying the migration of epithelial tubes during organogenesis. Mutations in the mig-17/ADAMTS gene cause misdirected migration of DTCs during gonad formation, resulting in deformed gonad arms. An amino-acid substitution in RPL- 20 corresponding to the mammalian RPL18a/eL20, a component of the 60S ribosomal large subunit, showed a slow growth phenotype and strongly suppressed the mig-17 gonadal defects. Slow-growing mutants clk-1 and clk-2 also suppressed mig-17, although weaker than rlp-20 mutants. MIG-17 recruits FBL-1C/fibulin-1C to the gonadal basement membrane to regulate DTC migration. Reducing the gene dosage of fbl-1 by half partially compromised the suppressor activity of the mutant rpl-20 gene on mig-17. Analysis using the mNeonGreen-FBL-1 reporter revealed that its localization to the gonadal basement membrane was significantly reduced in mig-17, whereas it was recovered to the wild-type levels in mig-17; rpl-20 double mutants. These results indicate that the rpl-20 mutation suppresses mig-17 gonadal defects through dual mechanisms: deceleration of growth rate and enhancement of FBL-1C recruitment to the gonadal basement membrane.

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Nishiwaki, K., Kim, H.-S., Mitsuzumi, K., Kondo, S., Yamaoka, R., Ihara, S., Otsuka, H., Kubota, Y., Fujiwara, T., Shibata, Y.. 2023-03-29. Ribosomal protein mutation suppresses gonadal leader cell migration defects in mig-17/ADAMTS mutants in Caenorhabditis elegans. https://doi.org/10.1101/2023.03.28.534640

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