In Saccharomyces cerevisiae, the Y family DNA polymerase (Pol) regulates genome stability in response to different forms of environmental stress by translesion DNA synthesis. To elucidate the role of Pol in oxidative stress-induced DNA damage, we deleted or overexpressed the corresponding gene RAD30 and used transcriptome analysis to screen the potential genes associated with RAD30 to respond to DNA damage. Under 2 mM H 2 O 2 treatment, the deletion of RAD30 resulted in a 2.2-fold decrease in survival and a 2.8-fold increase in DNA damage, whereas overexpression of RAD30 increased survival and decreased DNA damage by 1.2-and 1.4-fold, respectively, compared with the wild-type strain. Transcriptome and phenotypic analyses identified Lsm12 as a main factor involved in oxidative stress-induced DNA damage. Deleting LSM12 caused growth defects, while its overexpression enhanced cell growth under 2 mM H 2 O 2 treatment. This effect was due to the physical interaction of Lsm12 with the UBZ domain of Pol to enhance Pol deubiquitination through Ubp3 and consequently promote Pol recruitment. Overall, these findings demonstrate that Lsm12 is a novel regulator mediating Pol deubiquitination to promote its recruitment under oxidative stress. Furthermore, this study provides a potential strategy to maintain the genome stability of industrial strains during fermentation. IMPORTANCE Pol was shown to be critical for cell growth in the yeast Saccharomyces cerevisiae, and deletion of its corresponding gene RAD30 caused a severe growth defect under exposure to oxidative stress with 2 mM H 2 O 2 . Furthermore, we found that Lsm12 physically interacts with Pol and promotes Pol deubiquitination and recruitment. Overall, these findings indicate Lsm12 is a novel regulator mediating Pol deubiquitination that regulates its recruitment in response to DNA damage induced by oxidative stress.
Senile and disuse osteoporosis have distinct bone turnover status and lack effective treatments. In this study, senescence-accelerated mouse prone 8 (SAMP8) and hindlimb unloading mouse models were used to explore the protective effects of daphnetin on these two types of osteoporosis, and primary osteoblasts and bone marrow monocyte-derived osteoclasts, as well as pre-osteoblast MC3T3-E1, and osteoclast precursor RAW264.7 cells were used to investigate the underlying mechanisms. The results showed that daphnetin administration effectively improved bone remodeling in both senile and disuse osteoporosis, but with different mechanisms. In senile osteoporosis with low bone turnover, daphnetin inhibited NOX2-mediated ROS production in osteoblasts, resulting in accelerated osteogenic differentiation and bone formation, while in disuse osteoporosis with high bone turnover, daphnetin restored SIRT3 expression, maintained mitochondrial homeostasis, and additionally upregulated SOD2 to eliminate ROS in osteoclasts, resulting in attenuation of osteoclast differentiation and bone resorption. These findings illuminated that daphnetin has promising potential for the prevention and treatment of senile and disuse osteoporosis. The different mechanisms may provide clues and basis for targeted prevention and treatment of osteoporosis according to distinct bone turnover status.
Cell medium exchange is a crucial step for life science and medicine. However, conventional cell medium exchange methods, including centrifuging and filtering, show limited ability for micro‐volume cell samples such as circulating tumor cell (CTC) and circulating fetal cell (CFC). In this paper, we proposed an automatic medium exchange method for micro‐volume cell samples based on dielectrophoresis (DEP) in microfluidic chip. Fresh medium and cell suspension were introduced into the microfluidic channel as the laminar flow. Plane stair‐shaped interdigital electrodes were employed to drive the cells from the cell suspension to fresh media directly by DEP force. Additionally, we characterized and optimized the cell medium exchange according to both the theory and experiments. In the end, we achieved a 96.9% harvest rate of medium exchange for 0.3 μL samples containing micro‐volume cells. For implementing an automatic continuous cell medium exchange, the proposed method can be integrated into the automatic cell processing system conveniently. Furthermore, the proposed method is a great candidate in micro‐volume cell analysis and processing, cell electroporation, single cell sequencing, and other scenarios.
Optical density is commonly used as a simple and rapid indirect measurement method to estimate biomass concentration in liquid cultures. However, the object of optical density detection is often algae cells, colonies, and other microorganisms, few studies adopt optical density to quantitatively measure the concentration of cancer cells. In this paper, different liquid media and cancer cells were used to implement a full-wavelength spectral analysis by microplate reader to find the corresponding robust wavelength. According to the experimental results, we suggest measuring cell concentration at nearinfrared wavelengths, such as 850 nm, to facilitate the subsequent unification of protocols applicable to different cell types and culture conditions. Meanwhile, a portable flow cell sensor based on optical density is demonstrated. The calibration curves under various experimental conditions have high regression coefficient R 2 values, all greater than 0.99, which are expected to be used for online real-time measurement of cell concentration in biological reaction processes. This study provides the feasibility of using the optical density method as a quick and easy way for indirect quantitative measurement of cancer cell concentration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.