An
efficient cellular transporter is highly desirable for the therapeutic
applications of antisense phosphorodiamidate morpholino oligonucleotides
(PMOs) as Vivo-PMO and PPMO have limitations for in vivo study. We
report here a novel internally tetraguanidinium-linked nonpeptidic
cellular transporter having a conformationally rigid backbone composed
of pharmacologically compatible heterocyclic six-membered rings which
internalizes efficiently into cells in full growth medium and ubiquitously
distributed into zebrafish embryos. It efficiently transports antisense
PMO in vitro and in vivo zebrafish embryos. Comparative study with
Gene Tools Vivo-PMO revealed that our cellular-transporter conjugated
PMO shows better antisense efficacy.
One of the crucial regulators of embryonic patterning and tissue development is the Hedgehog-glioma (Hh-Gli) signalling pathway; its uncontrolled activation has been implicated in different types of cancer in adult tissues. Primary cilium is one of the important factors required for the activation of Hh signalling, as it brings the critical components together for key protein-protein interactions required for Hh pathway regulation. Most of the synthetic and natural small molecule modulators of the pathway primarily antagonise Smoothened (Smo) or other effectors like Hh ligand or Gli. Here, we report a previously described Hh antagonist, with a pyrimidine-indole hybrid (PIH) core structure, as an inhibitor of ciliogenesis. The compound is unique in its mode of action, as it shows perturbation of microtubule dynamics in both cell-based assays and in vivo systems (zebrafish embryos). Further studies revealed that the probable targets are α-tubulin and its acetylated form, found in the cytoplasm and primary cilia. PIH also showed axonal defasiculation in developing zebrafish embryos. We thus propose that PIH antagonises Hh signalling by repressing cilia biogenesis and disassembling α-tubulin from its stabilised form.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.