Antibodies to specific nucleic acid conformations are amongst the methods that have allowed the study of non-canonical (Watson-Crick) DNA structures in higher organisms. In this work, the structural limitations for the immunological detection of DNA.RNA hybrid duplexes were examined using specific RNA homopolymers as probes for homopolymer polydeoxyadenylic acid (poly(dA)).polydeoxythymidylic acid (poly(dT))-rich regions of Rhynchosciara americana (Diptera: Sciaridae) chromosomes. Anti-DNA.RNA duplexes did not react with the complex formed between chromosomal poly(dA) and exogenous polyuridylic acid (poly(rU)). Additionally, poly(rU) prevented the detection of polyadenylic acid.poly(dT) hybrid duplexes preformed in situ. These results raised the possibility that three-stranded structures rather than duplexes were formed in chromosomal sites. To test this hypothesis, the specificity of antibodies to triple-helical nucleic acids was reassessed employing distinct nucleic acid configurations. These antibodies were raised to the poly(dA).poly(rU).poly(rU) complex and have been used here for the first time in immunocytochemistry. Anti-triplex antibodies recognised the complex poly(dA).poly(rU).poly(rU) assembled with poly(rU) in poly(dA).poly(dT)-rich homopolymer regions of R. americana chromosomes. The antibodies could not detect short triplex stretches, suggesting the existence of constraints for triple-helix detection, probably related to triplex tract length. In addition, anti-poly(dA).poly(rU).poly(rU) antibodies reacted with the pericentric heterochromatin of RNase-treated polytene chromosomes of R. americana and Drosophila melanogaster. In apparent agreement with data obtained in cell types from other organisms, the results of this work suggest that significant triple-helix DNA extensions can be formed in pericentric regions of these species.
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http://dx.doi.org/10.1007/s10577-009-9075-5 | DOI Listing |
BMC Infect Dis
January 2025
Department of Otolaryngology-Head and Neck Surgery, Zhongshan Hospital, Fudan University, Fenglin Road 180, Shanghai, 200032, China.
Objective: To identify specific clinical signs of Omicron pharyngitis infection.
Methods: A clinical cross-sectional retrospective study was designed to analyze the primary symptoms of pharyngitis in outpatients seeking treatment for sore throat. Pharyngeal congestion, mucosal edema, were measured using a visual analogue assessment score (0-10) while the presence of ulcers, no-tonsil-swelling, no-tonsil-exudate.
Arch Virol
January 2025
Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization, College of Oceanography, Hohai University, Nanjing, Jiangsu, China.
In this study, a lytic phage, named PG216, was obtained from seawater collected in Qingdao, using Vibrio parahaemolyticus strain G299 as its host. Transmission electron microscopy revealed that phage PG216 has an icosahedral head with a diameter of 100 ± 6.7 nm and a contractible tail with a length of 126 ± 6.
View Article and Find Full Text PDFCurr Microbiol
January 2025
Key Laboratory of Basic and Application Research of Beiyao, Ministry of Education, Heilongjiang University of Chinese Medicine, Harbin, 150040, China.
Comprehending the interplay between the microbial communities of bulk soil (BS) and rhizosphere soil (RS) holds crucial significance in maintaining soil health and fertility, as well as enhancing crop quality. Our research focused on examining these microbial communities in BS and RS of Acanthopanax senticosus, along with their correlation with soil nutrients, across three distinct habitats in Yichun, Heilongjiang Province. To achieve this, we employed high-throughput sequencing technology, specifically targeting the 16S and amplicon regions.
View Article and Find Full Text PDFNat Chem
January 2025
Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA, USA.
Understanding the emergence of complex biochemical systems, such as protein translation, is a great challenge. Although synthetic approaches can provide insight into the potential early stages of life, they do not address the equally important question of why the complex systems of life would have evolved. In particular, the intricacies of the mechanisms governing the transfer of information from nucleic acid sequences to proteins make it difficult to imagine how coded protein synthesis could have emerged from a prebiotic soup.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Ophthalmology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Hirokoji, Kawaramachi, Kamigyoku, Kyoto, 602-0841, Japan.
Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe mucocutaneous disorders characterized by extensive tissue necrosis; they are often accompanied by severe ocular complications (SOC). The regulatory role of microRNAs (miRNAs) in modulating immune responses in SJS/TEN is not fully understood, particularly in relation to chronic SOC. We explored the expression profiles of specific miRNAs and their potential impact on the regulation of key innate immune genes in patients with SJS/TEN with SOC.
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