Modification of maternally defined H3K4me3 regulates the inviability of interspecific Xenopus hybrids

CRISPR/Cas-mediated mRNA knockdown in the embryos of Xenopus tropicalis

The Xenopus tropicalis (Western clawed frog) is an important amphibian model for genetics, developmental and regenerative biology, due to its diploid genetic background and short generation time. CRISPR-Cas13 and CRISPR interference (CRISPRi) systems have recently been employed to suppress mRNA expression in many organisms such as yeast, plants, and mammalian cells. However, no systematic study of these two systems has been carried out in Xenopus tropicalis. Here, we show that CRISPRi rather than CRISPR-Cas13 is an effective and suitable approach to suppress specific mRNA transcription in Xenopus tropicalis embryos. We demonstrated that CRISPRi composed of dCas9 and KRAB-MeCP2 (dCas9-KM) can efficiently target exogenous and endogenous transcripts in Xenopus tropicalis embryos. Moreover, our data suggest that the new KRAB domain from ZIM3 protein (ZIM3-KRAB, ZIM3K) alone has a comparable transcript targeting capacity in Xenopus tropicalis embryos to the traditional fusion repressor KRAB-MeCP2 in which the KRAB domain from KOX1 protein. In conclusion, our results demonstrate that CRISPRi rather than CRISPR-Cas13 is an efficient knockdown platform to explore specific gene function in Xenopus tropicalis embryos.

Preclinical Data Extrapolation to Clinical Reality: A Translational Approach

In vivo investigations are much more complex than trials conducted in a test tube; the results sometimes aren't as illuminating and could raise more questions than answers. Preclinical data projection into clinical truth is a transcriptional science that remains a compelling trial in drug development. Preclinical in vivo and in vitro education is important in novel drug's non-violent or active growth. Pharmacokinetic and metabolic research is necessary to better understand the chemical and biological effects of medicines and their metabolites. Information produced by such a policy can be used to progress Phase I studies, primarily for anticancer medication. Both living and deceased in vitro models are theoretically excellent preclinical tools for calculating the pharmacological action of counterparts from the same family, such as vinca alkaloids. The animal species most closely linked to humans are chosen based on metabolic patterns. The estimation of the duration of drug action, particularly for medicines with varied metabolic clearances (e.g., benzodiazepines); The empathetic or estimate of medicine relations, i.e., those defined for cyclosporin A and macrolide antibiotics; and Sclarification of the metabolic roots of individual inconsistencies in pharmaceutical action.

Mechanistic study of transcription factor Sox18 during heart development

Heart development is a delicate and complex process regulated by coordination of various signaling pathways. In this study, we investigated the role of sox18 in heart development by modulating Wnt/β-Catenin signaling pathways. Our spatiotemporal expression analysis revealed that sox18 is mainly expressed in the heart, branchial arch, pharyngeal arch, spinal cord, and intersegmental vessels at the tailbud stage of Xenopus tropicalis embryo. Overexpression of sox18 in the X. tropicalis embryos causes heart edema, while loss-of-function of sox18 can change the signal of developmental heart marker gata4 at different stages, suggesting that sox18 plays an essential role in the development of the heart. Knockdown of SOX18 in human umbilical vein endothelial cells suggests a link between Sox18 and β-CATENIN, a key regulator of the Wnt signaling pathway. Sox18 negatively regulates islet1 and tbx3, the downstream factors of Wnt/β-Catenin signaling, during the linear heart tube formation and the heart looping stage. Taken together, our findings highlight the crucial role of Sox18 in the development of the heart via inhibiting Wnt/β-Catenin signaling.