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Gui, C.

Publications and source records attributed to Gui, C..

7 recordsLinked to original sources

Markers of mitochondrial function and oxidative metabolism in female skeletal muscle do not display intrinsic circadian regulation

Mitochondria are key regulators of metabolism and ATP supply in skeletal muscle, while circadian rhythms influence many physiological processes. However, whether mitochondrial function is intrinsically regulated in a circadian manner in mouse skeletal muscle is inadequately understood. Accordingly, we measured post-absorptive transcript abundance of markers of mitochondrial biogenesis, dynamics, and metabolism (extensor digitorum longus [EDL], soleus, gastrocnemius), protein abundance of electron transport chain complexes (EDL and soleus), enzymatic activity of SDH (tibialis anterior and plantaris), and maximum uncoupled respiration (tibialis anterior) in different skeletal muscles from female C57BL/6NJ mice at four zeitgeber times (ZT), ZT 1, 7, 13, and 19. Our findings demonstrate that markers of mitochondrial function and oxidative metabolism do not display intrinsic time-of-day regulation at the gene, protein, enzymatic, or functional level. The core-clock genes Bmal1 and Dbp exhibited intrinsic circadian rhythmicity in skeletal muscle (i.e., EDL, soleus, gastrocnemius) and circadian amplitude varied by muscle type. These findings demonstrate that female mouse skeletal muscle does not display circadian regulation of markers of mitochondrial function or oxidative metabolism over 24 hours.

physiology↗

TOC1 phosphorylation disproportionally enhances chromatin binding at rhythmic gene promoters

Protein phosphorylation is a key regulatory mechanism in circadian systems. TIMING OF CAB EXPRESSION 1(TOC1) is a core transcriptional repressor in the plant circadian system that is phosphorylated near its N-terminus. Phenotype testing of single and multi-phosphosite mutants shows incomplete rescue of the short period toc1 mutant. We establish that TOC1 phosphorylation (particularly at S175) is necessary for optimal interaction with FAR-RED ELONGATED HYPOCOTYL3 (FHY3) and PHYTOCHROME INTERACTING FACTOR 5 (PIF5) at the CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1) promoter to downregulate CCA1 expression. At the same time, expression of the closely related LATE ELONGATED HYPOCOTYL (LHY) also requires TOC1, but is independent of the TOC1 phosphorylation state, suggesting different TOC1-dependent mechanisms in the repression of these two genes. We additionally show how phosphorylation-dependent interactions of TOC1 at specific clock gene promoters selectively regulate these circadian system components more acutely than non-rhythmic genes. Our genome-wide analysis shows that the phosphostate of TOC1 is important for optimal chromatin presence and robust rhythmic gene expression.

plant biology↗

Microbial Weathering Analysis of Anshun Tunbao Artifacts

AbstractsCultural heritages are the crystallization of human technology, culture and embody the efforts of many craftsmen in ancient times. Wooden cultural heritages are affected by their own materials, and are very susceptible to microbial invasion under suitable temperature and humidity conditions. This project mainly studies the microbial weathering of the core wood carving masks and wooden ancient stage in Anshun Tunpu cultural heritage, and uses scanning electron microscopy, high-throughput sequencing and traditional culture methods to analyze the characteristics of their microbial communities, and finds that the bacteria represented by Pseudomonas, Paenibacillus and Stenotrophomonas, and the fungi represented by Cladosporium, Alternaria and Aspergillus, are the core microorganisms shared by indoor and outdoor cultural heritage. The dominant genera such as Pseudomonas, Stenotrophomonas, and Cladosporium showed lignocellulose deradation ability. By cultivating insect eggs extracted from sampled specimens and analyzing the correlation with surface microbiota, we verified the role of insect eggs as vectors in dispersing key microbial communities. We speculate that these insects are likely to be Anobiidae family. Furthermore, by comparing the microbial compositions under different climatic conditions, we validated the influence of temperature, humidity, vegetation diversity, and microbial intrinsic structures on microbial growth. Therefore, monitoring the surrounding environment is crucial in microbial weathering studies and cultural heritage preservation efforts. This study pioneered the investigation of microbial weathering aspects on unique heritage of the Tuenbao culture, emphasizing the importance of preserving distinctive ethnic cultures. Additionally, it presented a case study on the microbial weathering of wooden artifacts in karst landscape environments.

microbiology↗

Reconstructing cell histories in space with image-readable base editor recording

Knowing the ancestral states and lineage relationships of individual cells could unravel the dynamic programs underlying development. Engineering cells to actively record information within their own genomic DNA could reveal these histories, but existing recording systems have limited information capacity or disrupt spatial context. Here, we introduce baseMEMOIR, which combines base editing, sequential hybridization imaging, and Bayesian inference to allow reconstruction of high-resolution cell lineage trees and cell state dynamics while preserving spatial organization. BaseMEMOIR stochastically and irreversibly edits engineered dinucleotides to one of three alternative image-readable states. By genomically integrating arrays of editable dinucleotides, we constructed an embryonic stem cell line with 792 bits of recordable, image-readable memory, a 50-fold increase over the state of the art. Simulations showed that this memory size was sufficient for accurate reconstruction of deep lineage trees. Experimentally, baseMEMOIR allowed precise reconstruction of lineage trees 6 or more generations deep in embryonic stem cell colonies. Further, it also allowed inference of ancestral cell states and their quantitative cell state transition rates, all from endpoint images. baseMEMOIR thus provides a scalable framework for reconstructing single cell histories in spatially organized multicellular systems.

synthetic biology↗

The Natural Products Discovery Center: Release of the First 8490 Sequenced Strains for Exploring Actinobacteria Biosynthetic Diversity

Actinobacteria, the bacterial phylum most renowned for natural product discovery, has been established as a valuable source for drug discovery and biotechnology but is underrepresented within accessible genome and strain collections. Herein, we introduce the Natural Products Discovery Center (NPDC), featuring 122,449 strains assembled over eight decades, the genomes of the first 8490 NPDC strains (7142 Actinobacteria), and the online NPDC Portal making both strains and genomes publicly available. A comparative survey of RefSeq and NPDC Actinobacteria highlights the taxonomic and biosynthetic diversity within the NPDC collection, including three new genera, hundreds of new species, and [~]7000 new gene cluster families. Selected examples demonstrate how the NPDC Portals strain metadata, genomes, and biosynthetic gene clusters can be leveraged using genome mining approaches. Our findings underscore the ongoing significance of Actinobacteria in natural product discovery, and the NPDC serves as an unparalleled resource for both Actinobacteria strains and genomes.

microbiology↗

A short course of antibiotics selects for persistent resistance in the human gut

Understanding the relationship between antibiotic use and the evolution of antimicrobial resistance is vital for effective antibiotic stewardship, yet animal models and in vitro experiments poorly replicate real-world conditions. To elucidate how resistance evolves in vivo, we exposed 60 human subjects to ciprofloxacin and used longitudinal stool samples and a new computational method to assemble genomes for 5665 populations of commensal bacterial species within subjects. Analysis of 2.27M polymorphic sequence variants revealed 513 populations that underwent selective sweeps. We found convergent evolution focused on DNA gyrase and evidence of dispersed selective pressure at other genomic loci. Nearly 10% of susceptible bacterial populations evolved towards resistance through sweeps that involved mutations in a specific amino acid in gyrase. Evolution towards resistance was predicted by population abundances before and during the exposure. 89% of gyrase sweeps and the majority of all sweeps persisted more than 10 weeks. This work quantifies the direct relationship between antibiotic usage and the evolution of resistance within the gut communities of individual human hosts.

evolutionary biology↗

Detection of local growth patterns in longitudinally imaged low-grade gliomas

BackgroundDiffuse low-grade gliomas (LGGs) are primary brain tumors with infiltrative, anisotropic growth related to surrounding white and grey matter structures. In this study, we illustrate the use of deformation-based morphometry (DBM) as a simple and objective method to study the local change in growth patterns of LGGs. MethodsAn imaging pipeline was developed involving the creation of patient-specific average templates and nonlinear registration of pre-treatment follow-up MRIs to the average template. Jacobian maps were derived and analyzed to identify areas of tissue expansion and contraction over time. ResultsOur analysis demonstrates that tissue expansion occurs primarily around the edges of the tumor, while the lesion core and areas adjacent to obstacles, such as the skull, show no significant growth. Tumors also appeared to grow faster and predominantly in areas of white matter. Regions of the brain surrounding the lesion showed slight contraction over time, likely representing compression due to mass effect of the tumor. ConclusionsWe demonstrate that DBM is a useful clinical tool to understand the long-term clinical course of an individuals tumor and identify areas of rapid growth, which can explain the clinical signs and symptoms, predict future symptoms, and guide targeted diagnostics and therapy. HighlightsO_LILow-grade glioma expansion occurs primarily around the edges of the tumor. C_LIO_LITumor cores and tissue next to obstacles show no significant growth over time. C_LIO_LIDBM provides a clinically valuable assessment of local tumor growth and activity. C_LI

cancer biology↗