Light-induced injury in mouse embryos revealed by single-cell RNA sequencing

BACKGROUND: Light exposure is a common stress factor in in vitro manipulation of embryos in the reproductive center. Many studies have shown the deleterious effects of high-intensity light exposure in different animal embryos. However, no transcriptomic studies have explored the light-induced injury and response in preimplantation embryos. RESULTS: Here, we adopt different time-courses and illumination intensities to treat mouse embryos at the 2-cell stage and evaluate their effects on blastulation. Meanwhile, single-cell transcriptomes from the 2-cell to blastocyst stage were analyzed after high-intensity light exposure. These data show that cells at each embryonic stage can be categorized into different light conditions. Further analyses of differentially expressed genes and GO terms revealed the light-induced injury as well as the potential repair response after high-intensity lighting. Maternal-to-zygote transition is also affected by the failure to remove maternal RNAs and deactivate zygotic genome expression. CONCLUSION: Our work revealed an integrated response to high-intensity lighting, involving morphological changes, long-lasting injury effects, and intracellular damage repair mechanisms.

Downregulation of TGF-ß1 suppressed proliferation and increased chemosensitivity of ovarian cancer cells by promoting BRCA1/Smad3 signaling

BACKGROUND: Studies have demonstrated that transforming growth factor beta-1 (TGF-ß1) exhibits oncogenic activity in different types of cancer, including ovarian cancer (OC). However, its regulatory mechanism in OC and whether TGF-ß1 is involved in chemosensitivity regulation remains unclear. Thus, the aim of this study was to investigate the role of TGF-ß1 in OC. METHODS: The OC cell line SKOV3 was employed, and TGF-ß1 overexpression or knockdown vectors were constructed. The cell proliferation of SKOV3 was evaluated with the cell counting kit (CCK8) kit after treatment with different concentrations of cis-platinum. Western blot and protein immunoprecipitation were employed to detect changes in BRCA1 and Smad3 expression and their interactions. Tumor growth in nude mice was evaluated. RESULTS: The results showed that TGF-ß1 knockdown increased chemosensitivity by promoting BRCA1 expression and Smad3 phosphorylation. In vivo studies showed that TGF-ß1 knockdown significantly inhibited the growth of tumors, also by upregulating BRCA1 expression and Smad3 phosphorylation. CONCLUSION: Taken together, our results suggest that TGF-ß1 knockdown inhibits tumor growth and increases chemosensitivity by promotion of BRCA1/Smad3 signaling.