Den Hertog, J. | bioRxiv Science

bioRxiv2024

Migration of Kupffers vesicle derived cells is essential for tail morphogenesis in zebrafish embryos

A phenotypic screen of fungal filtrates on developing zebrafish embryos identified metabolites from the fungus Ceratocystis populicola to induce ectopic tail formation, including a split notochord and a duplicated caudal fin. Chemical analyses led to the identification of monoterpene alcohols, in particular geraniol, as active compounds inducing ectopic tail formation during a specific 4 h time window during tail bud stage. Embryos from Tupfel long fin zebrafish (TL) were more susceptible to ectopic tail formation by geraniol than embryos from Wild Indian Karyotpe (WIK) zebrafish, indicating zebrafish strain specificity. RNA sequencing on tail buds of 15-somite stage embryos revealed downregulation of essential genes of the retinoic acid signaling pathway and differential expression of cyp26a1 and fgf8a and downstream hox-genes was validated. Time-lapse imaging revealed that Kupffers vesicle derived cells failed to migrate shorty after Kupffers vesicle collapse upon geraniol treatment and these cells failed to merge with progenitors from the tail bud. Instead, these cells contributed to an ectopic tail, expressing markers for presomitic mesoderm, somite and notochord tissue. Taken together, our data suggests that Kupffers vesicle cells harbor tail progenitor capacity, and proper migration of these cells is essential for normal tail morphogenesis. Summary StatementInhibition of Kupffers vesicle derived cell migration affected tail morphogenesis and resulted in ectopic tail formation in zebrafish embryos.

developmental biology↗

bioRxiv2020

Peptide-based Inhibitors of Protein-Protein Interactions of Src Homology 2 Domain-Containing Phosphatase 2

We developed a new class of inhibitors of protein-protein interactions of the SHP2 phosphatase, which is pivotal in multiple signaling pathways and a central target in the therapy of cancer and rare diseases. Currently available SHP2 inhibitors target the catalytic site or an allosteric pocket but lack specificity or are ineffective on disease-associated SHP2 mutants. Based on the consideration that pathogenic lesions cause signaling hyperactivation due to increased SHP2 association with cognate proteins, we developed peptide-based molecules with low nM affinity for the N-terminal Src homology domain of SHP2, good selectivity, stability to degradation and an affinity for pathogenic variants of SHP2 up to 20 times higher than for the wild-type protein. The best peptide reverted the effects of a pathogenic variant (D61G) in zebrafish embryos. Our results provide a novel route for SHP2-targeted therapies and a tool to investigate the role of protein-protein interactions in the function of SHP2.

biophysics↗