Natural and artificial nucleases have extensive applications in biotechnology and biomedicine. The exploration of protein with potential DNA cleavage activity also inspires the design of artificial nuclease and helps to understand the physiological process of DNA damage. In this study, we engineered four human cytochrome c (Cyt c) mutants (N52S, N52A, I81N, and I81D Cyt c), which showed enhanced DNA cleavage activity and degradation in comparison with WT Cyt c, especially under acidic conditions. The mechanism assays revealed that the superoxide (O) plays an important role in the nuclease reaction. The kinetic assays showed that the peroxidase activity of the I81D Cyt c mutant enhanced up to 9-fold at pH 5. This study suggests that the mutations of Ile81 and Asn52 in Ω-loop C/D are critical for the nuclease activity of Cyt c, which may have physiological significance in DNA damage and potential applications in biomedicine.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bbapap.2023.140897 | DOI Listing |
Biomolecules
January 2025
Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba 305-0047, Japan.
Synthetic cytosine-phosphate-guanine oligodeoxynucleotides (CpG ODNs) are promising candidates for vaccine adjuvants, because they activate immune responses through the Toll-like receptor 9 (TLR9) pathway. However, unmodified CpG ODNs are quickly degraded by serum nucleases, and their negative charge hinders cellular uptake, limiting their clinical application. Our group previously reported that guanine-quadruplex (G4)-forming CpG ODNs exhibit enhanced stability and cellular uptake.
View Article and Find Full Text PDFCell Biosci
January 2025
Jinshan Hospital Center for Neurosurgery, Jinshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 201508, China.
In recent years, mitochondrial DNA (mtDNA) base editing systems have emerged as bioengineering tools. DddA-derived cytosine base editors (DdCBEs) have been developed to specifically induce C-to-T conversion in mtDNA by the fusion of sequence-programmable transcription activator-like effector nucleases (TALENs) or zinc-finger nucleases (ZFNs), and split deaminase derived from interbacterial toxins. Similar to DdCBEs, mtDNA adenine base editors have been developed with the ability to introduce targeted A-to-G conversions into human mtDNA.
View Article and Find Full Text PDFZool Res
January 2025
Stomatological Hospital, School of Stomatology, Southern Medical University, Guangzhou, Guangdong 510280, China. E-mail:
Severe combined immunodeficiency disease (SCID), characterized by profound immune system dysfunction, can lead to life-threatening infections and death. Animal models play a pivotal role in elucidating biological processes and advancing therapeutic strategies. Recent advances in gene-editing technologies, including zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), CRISPR/Cas9, and base editing, have significantly enhanced the generation of SCID models.
View Article and Find Full Text PDFZool Res
January 2025
Research & Development Institute of Northwestern Polytechnical University in Shenzhen, Shenzhen, Guangdong 518057, China.
DNA2, a multifunctional enzyme with structure-specific nuclease, 5 -to-3 helicase, and DNA-dependent ATPase activities, plays a pivotal role in the cellular response to DNA damage. However, its involvement in cerebral ischemia/reperfusion (I/R) injury remains to be elucidated. This study investigated the involvement of DNA2 in cerebral I/R injury using conditional knockout (cKO) mice ( -Cre) subjected to middle cerebral artery occlusion (MCAO), an established model of cerebral I/R.
View Article and Find Full Text PDFBiosens Bioelectron
January 2025
Lab of Biosystem and Microanalysis, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, Shanghai, 200237, China; School of Chemistry and Chemical Engineering, Shihezi University, Xinjiang, 832000, China. Electronic address:
RNA imaging technology is essential for understanding the complex RNA regulatory mechanisms and serves as a powerful tool for disease diagnosis. However, conventional RNA imaging methods often require multiple fluorescent tags for the specific labeling of individual targets, complicating both the imaging process and subsequent analysis. Herein, we develop an RNA sensor that integrates a blocked CRISPR RNA (crRNA)-based conformational switch with a controllable CRISPR activation (CRISPRa) system and apply for RNA imaging.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!