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Metabolic programming is deeply intertwined with early embryonic development including zygotic genome activation (ZGA), the polarization of zygotic cells, and cell fate commitment. It is crucial to establish a noninvasive imaging technology that spatiotemporally illuminates the cellular metabolism pathways in embryos to track developmental metabolism in situ. In this study, we used two high‐quality genetically encoded fluorescent biosensors, SoNar for NADH/NAD+ and iNap1 for NADPH, to characterize the dynamic regulation of energy metabolism and redox homeostasis during early zygotic cleavage. Our imaging results showed that NADH/NAD+ levels decreased from the early to the late two‐cell stage, whereas the levels of the reducing equivalent NADPH increased. Mechanistically, transcriptome profiling suggested that during the two‐cell stage, zygotic cells downregulated the expression of genes involved in glucose uptake and glycolysis, and upregulated the expression of genes for pyruvate metabolism in mitochondria and oxidative phosphorylation, with a decline in the expression of two peroxiredoxin genes, Prdx1 and Prdx2. Collectively, with the establishment of in situ metabolic monitoring technology, our study revealed the programming of redox metabolism during ZGA. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer diagnosed in women. Breast cancer research is currently based mainly on animal models and traditional cell culture. However, the inherent species gap between humans and animals, as well as differences in organization between organs and cells, limits research advances. The breast cancer organoid can reproduce many of the key features of human breast cancer, thereby providing a new platform for investigating the mechanisms underlying the development, progression, metastasis and drug resistance of breast cancer. The application of organoid technology can also promote drug discovery and the design of individualized treatment strategies. Here, we discuss the latest advances in the use of organoid technology for breast cancer research. [ABSTRACT FROM AUTHOR]

TIGAR (TP53‐induced glycolysis and apoptosis regulator) is a p53‐inducible gene and its expression resulted in controlling metabolism and protection from apoptosis. Furthermore, TIGAR participated in promoting the pentose phosphate pathway and help in lowering intracellular reactive oxygen species. miR‐885‐5p has also been reported to be involved in liver tumorigenesis, but whether miR‐885‐5p has a regulatory effect on TIGAR expression is unknown. In this study, we found that their levels were correlated to each other and positively related to cell malignancy. Exogenous miR‐885‐5p induced TIGAR expression through a p53‐independent pathway. The promoter region of TIGAR harbors two tandem putative miR‐885‐5p target sites. Cotransfection of synthetic miR‐885 with TIGAR promoter reporter constructs significantly enhanced TIGAR promoter activity via binding with target sites. Furthermore, miR‐885‐5p and its precursor pre‐miR‐885 had the same stimulatory impact on TIGAR expression. Chromatin immunoprecipitation analysis further verified that increased miR‐885‐5p potentiated the accessibility of TIGAR promoter chromatin to transcriptional factors and facilitated TIGAR expression. miR‐885‐5p and its precursor both can interact mechanically with TIGAR promoter binding site and alter local chromatin structure, and subsequently upregulate TIGAR expression and participate in liver tumorigenesis. [ABSTRACT FROM AUTHOR]

The black-spotted tokay and the red-spotted tokay are morphologically distinct and have largely allopatric distributions. The black-spotted tokay is characterized by a small body size and dark skin with sundry spots, while the red-spotted tokay has a relatively large body size and red spots. Based on morphological, karyotypic, genetic, and distribution differences, recent studies suggested their species status; however, their classifications remain controversial, and additional data such as ecological niches are necessary to establish firm hypotheses regarding their taxonomic status. We reconstructed their ecological niches models using climatic and geographic data. We then performed niche similarity tests (niche identity and background tests) and point-based analyses to explore whether ecological differentiation has occurred, and whether such differences are sufficient to explain the maintenance of their separate segments of environmental ranges. We found that both niche models of the black- and the red-spotted tokay had a good fit and a robust performance, as indicated by the high area under the curve ( AUC) values ('black' = 0.982, SD = ± 0.002, 'red' = 0.966 ± 0.02). Significant ecological differentiation across the entire geographic range was found, indicating that the involvement of ecological differentiation is important for species differentiation. Divergence along the environmental axes is highly associated with climatic conditions, with isothermality being important for the 'black' form, while temperature seasonality, precipitation of warmest quarter, and annual temperature range together being important for the 'red' form. These factors are likely important factors in niche differentiation between the two forms, which result in morphological replacement. Overall, beside morphological and genetic differentiation information, our results contribute to additional insights into taxonomic distinction and niche differentiation between the black- and the red-spotted tokay. [ABSTRACT FROM AUTHOR]