PRDM9 directs human meiotic crossover hot spots to intergenic sequence motifs, whereas budding yeast hot spots overlap regions of low nucleosome density (LND) in gene promoters. To investigate hot spots in plants, which lack PRDM9, we used coalescent analysis of genetic variation in Arabidopsis thaliana. Crossovers increased toward gene promoters and terminators, and hot spots were associated with active chromatin modifications, including H2A.Z, histone H3 Lys4 trimethylation (H3K4me3), LND and low DNA methylation. Hot spot-enriched A-rich and CTT-repeat DNA motifs occurred upstream and downstream, respectively, of transcriptional start sites. Crossovers were asymmetric around promoters and were most frequent over CTT-repeat motifs and H2A.Z nucleosomes. Pollen typing, segregation and cytogenetic analysis showed decreased numbers of crossovers in the arp6 H2A.Z deposition mutant at multiple scales. During meiosis, H2A.Z forms overlapping chromosomal foci with the DMC1 and RAD51 recombinases. As arp6 reduced the number of DMC1 or RAD51 foci, H2A.Z may promote the formation or processing of meiotic DNA double-strand breaks. We propose that gene chromatin ancestrally designates hot spots within eukaryotes and PRDM9 is a derived state within vertebrates.
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http://dx.doi.org/10.1038/ng.2766 | DOI Listing |
Anal Chim Acta
January 2025
Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Department of Biomedical Engineering, Jinan University, Guangzhou, 510632, China. Electronic address:
Background: The multifunctional cytokine interleukin-6 (IL-6) plays a pivotal role in chronic and acute inflammatory responses, underscoring the importance of accurately determining IL-6 levels for early diagnosis, prevention, and treatment of inflammation.
Results: This study developed a versatile and innovative single-particle surface-enhanced Raman spectroscopy (SERS) sensing platform for the precise and sensitive quantification of IL-6 in complex samples using a novel one-pot synthesized, silver ions-doped three-dimensional porous gold microparticles (PGMs) with abundant hot spots for robust SERS enhancement. By rationally designing rich cytosine-Ag-cytosine base pairs between IL-6 aptamers and complementary chains on the PGMs, we harnessed the SERS-enhancing effect to achieve highly sensitive and specific IL-6 quantification within a wide range of 10 to 10 mg/mL and a limit of detection (LOD) of 0.
Anal Chim Acta
January 2025
Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo. C/ Julián Clavería 8, 33006, Oviedo, Spain; Health Research Institute of Asturias (ISPA), Avda de Roma s/n, 33011, Oviedo, Spain. Electronic address:
Background: 3D cellular structures have been considered the following step in the evaluation of drugs penetration after 2D cultures since they are more physiologically representative in cancer cell biology. Here the penetration capabilities of Pt (IV)-loaded ultrasmall iron oxide nanoparticles in 143B osteosarcoma multicellular spheroids of different sizes is conducted by a multidimensional quantitative approach. Single cell (SC) and imaging techniques (laser ablation, LA) coupled to inductively coupled plasma-mass spectrometry (ICP-MS) are used to visualize their penetration pathways and distribution in comparison to those of cisplatin.
View Article and Find Full Text PDFJMIR Public Health Surveill
January 2025
Laboratoire AGEIS, Université Grenoble Alpes, La Tronche Cedex, France.
Background: Although agricultural health has gained importance, to date, much of the existing research relies on traditional epidemiological approaches that often face limitations related to sample size, geographic scope, temporal coverage, and the range of health events examined. To address these challenges, a complementary approach involves leveraging and reusing data beyond its original purpose. Administrative health databases (AHDs) are increasingly reused in population-based research and digital public health, especially for populations such as farmers, who face distinct environmental risks.
View Article and Find Full Text PDFWorld Neurosurg
January 2025
Department of Orthopaedic Surgery, the Bozhou Hospital Affiliated to Anhui Medical University, Bozhou, Anhui, China. Electronic address:
Background: Acute spinal cord injury causes severe motor and sensory dysfunction, significantly burdening individuals and society. This study uses bibliometric analysis to identify research trends and key areas, providing insights for future advancements in treatment.
Methods: Scientific publications on acute spinal cord injury were collected from PubMed and the Web of Science Core Collection (WoSCC) between 2000 and 2022.
Sci Total Environ
January 2025
Department of Forest Biodiversity, Faculty of Forestry, University of Agriculture, al. 29 Listopada 46, 31-425 Kraków, Poland. Electronic address:
Tree-related Microhabitats (TreMs) are essential for sustaining forest biodiversity. Although TreMs represent ephemeral resources that are spread across the landscape, their spatial distribution within temperate forests remains poorly understood. To address this knowledge gap, we conducted a study on 90 sample plots (0.
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