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Di, A.

Publications and source records attributed to Di, A..

3 recordsLinked to original sources

Rapid production of modified cattle and sheep from spermatid-like stem cells

Genome-modified ruminants, such as cattle and sheep, are important germplasm for agricultural applications. Haploid androgenetic stem cells (haSCs) can support the full-term development of embryos upon intracytoplasmic haSCs injection (iCHI) into intact oocytes. Thus, haSCs are invaluable resources for studying economic traits and significantly impact livestock breeding; however, ruminant haSCs have yet to be obtained. Here, we report the derivation of cattle and sheep haSCs using a recombinant FACE medium. These cells display characteristics of formative-state pluripotency and can differentiate into three germ layers, both in vitro and in vivo. Interestingly, the ectopic expression of protamine in haSCs converts their nuclei into a spermatid-like structure and synergistic enhancement of full-term development of iCHI embryos, named as Pro-iCHI approach. Furthermore, gene-modified cattle and sheep can be efficiently produced through the combinatorial use of the CRISPR and Pro-iCHI approach. Overall, Pro-iCHI provides an easy-to-manipulate agrobiotechnology tool for rapidly producing genetically modified livestock.

bioengineering↗

Endosomal Trafficking of Two Pore K+ Efflux Channel TWIK2 to Plasmalemma Mediates NLRP3 Inflammasome Activation and Inflammatory Injury

Potassium efflux via the two pore K+ channel TWIK2 is a requisite step for the activation of the NLRP3 inflammasome, however it is unclear how the efflux is activated in response to cues. Here we report that during homeostasis, TWIK2 resides in endosomal compartments. TWIK2 is transported by endosomal fusion to the plasmalemma in response to increased extracellular ATP resulting in extrusion of K+ ATP-induced endosomal TWIK2 plasmalemma translocation is regulated by Rab11a. Deleting Rab11a or ATP ligated purinergic receptor P2X7 prevented endosomal fusion with the plasmalemma and K+ efflux and NLRP3 inflammasome activation in macrophages. Adoptive transfer of Rab11a-deleted macrophages into mouse lungs prevented NLRP3 inflammasome activation and inflammatory lung injury. Rab11a-mediated endosomal trafficking in macrophages thus regulates TWIK2 abundance and activity on the cell surface and downstream activation of the NLRP3 inflammasome. Endosomal trafficking of TWIK2 to the plasmalemma is therefore a potential therapy target in acute or chronic inflammatory states.

cell biology↗

Significant improvement of reprogramming efficiency by transient overexpression of ZGA inducer Dux but not Dppa2/4

Cloned animal have been reported by somatic cell nuclear transfer (SCNT) for many years. However, the SCNT is extremely inefficient, and zygotic genome activation (ZGA) is required for SCNT and chemical mediated reprogramming. To identify candidate factors that facilitate ZGA in reprogramming, we performed siRNA-repressor and mRNA-inducer screening, which revealed Dux, Dppa2, and Dppa4 as key factors enhancing the ZGA in SCNT. Direct injection of ZGA-inducers had no significant effect on the SCNT blastocyst formation, and even destroyed the ZGA. Through a inducible Dux transgenic mouse model, we demonstrate that transient overexpression of Dux not only improved SCNT efficiency, but also increased the efficiency of chemical reprogramming. Transcriptome profiling revealed that Dux treated SCNT embryos were similar to fertilized embryos. Furthermore, transient overexpression of Dux combined with inactivation of DNA methyltransferases (Dnmts) further promote the overall development of SCNT-derived animals. These findings enhance our understanding of ZGA-regulators in somatic reprogramming.

bioengineering↗