Excessive abdominal fat deposition negatively impacts poultry meat production and carcass yield. Identification of novel adipogenesis regulators may help improve production performance declines caused by excessive fat deposition. NUMB Endocytic Adaptor Protein ( NUMB ) typically functions as a cell fate determinant and plays a significant role in cell development and various diseases. Here, we found that NUMB is abundantly expressed in chicken abdominal fat depots and is induced in cultured adipocytes following adipogenic treatment. The gain- and loss-of-function experiments demonstrated that NUMB promotes the proliferation and G1/S transition of chicken adipocytes, enhances adipocyte differentiation, and increases the expression of PPARγ1 transcript. Through mRNA-seq analysis and molecular experiments, we further confirmed that NUMB inhibits the transcriptional activation of the NOTCH1 pathway and the expression of the downstream transcription factor HES1 by inducing NOTCH1 degradation. Nevertheless, the inhibition of the NOTCH1 / HES1 axis alone cannot fully explain NUMB 's role in adipogenesis, as NUMB also regulates the expression of multiple adipogenic transcription factors such as E2F1 , EGR2 , and NR4A3 . Our data suggest that NUMB is a potent activator of adipogenesis and enhances our understanding of its regulatory mechanisms in chicken abdominal fat deposition.
The widely distributed β-carboline alkaloids exhibit promising psychopharmacological and biochemical effects. Harmine, a natural β-carboline, can inhibit insect growth and development with unclear mechanisms. In this study, harmine (at 0-200 mg/L) showed a dose-dependent inhibitory effect on the pupal weight, length, height, pupation rate and eclosion rate of fruit flies Drosophila melanogaster , which was similar to the inhibition induced by the well-known botanical insect growth regulator azadirachtin . Moreover, the expression levels of major regulators from the developmental signaling network were down-regulated during the pupal stage except Numb , Fringe , Yorkie and Pten . The Notch, Wnt, Hedgehog and TGF-β pathways mainly played vital roles in coping with harmine exposure in pupae stage, while the Hippo, Hedgehog and TGF-β elements were involved in the sex differences. Notch , Hippo , Hedgehog , Dpp and Armadillo were proved to be suppressed in the developmental inhibition with fly mutants, while Numb and Punt were increased by harmine. In conclusion, harmine significantly inhibited the development of Drosophila by negatively affecting their developmental signaling network during different stages. Our results establish a preliminary understanding of the developmental signaling network subjected to botanical component-induced growth inhibition and lay the groundwork for further application.
危险品化学品经营许可证（带存储）