DNA polymerase λ (Pol λ) is the sole member of family X DNA polymerase in plants and plays a crucial role in nuclear DNA damage repair. Here, we report the transcriptional up-regulation of Arabidopsis (Arabidopsis thaliana) AtPolλ in response to abiotic and genotoxic stress, including salinity and the DNA cross-linking agent mitomycin C (MMC). The increased sensitivity of atpolλ knockout mutants toward high salinity and MMC treatments, with higher levels of accumulation of double strand breaks (DSBs) than wild-type plants and delayed repair of DSBs, has suggested the requirement of Pol λ in DSB repair in plants. AtPolλ overexpression moderately complemented the deficiency of DSB repair capacity in atpolλ mutants. Transcriptional up-regulation of major nonhomologous end joining (NHEJ) pathway genes KU80, X-RAY CROSS COMPLEMENTATION PROTEIN4 (XRCC4), and DNA Ligase4 (Lig4) along with AtPolλ in Arabidopsis seedlings, and the increased sensitivity of atpolλ-2/atxrcc4 and atpolλ-2/atlig4 double mutants toward high salinity and MMC treatments, indicated the involvement of NHEJ-mediated repair of salinity- and MMC-induced DSBs. The suppressed expression of NHEJ genes in atpolλ mutants suggested complex transcriptional regulation of NHEJ genes. Pol λ interacted directly with XRCC4 and Lig4 via its N-terminal breast cancer-associated C terminus (BRCT) domain in a yeast two-hybrid system, while increased sensitivity of BRCT-deficient Pol λ-expressing transgenic atpolλ-2 mutants toward genotoxins indicated the importance of the BRCT domain of AtPolλ in mediating the interactions for processing DSBs. Our findings provide evidence for the direct involvement of DNA Pol λ in the repair of DSBs in a plant genome.
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http://dx.doi.org/10.1104/pp.113.219022 | DOI Listing |
JAMA Netw Open
January 2025
Division of Geriatrics, School of Medicine, University of California San Francisco.
Importance: The Walter Index is a widely used prognostic tool for assessing 12-month mortality risk among hospitalized older adults. Developed in the US in 2001, its accuracy in contemporary non-US contexts is unclear.
Objective: To evaluate the external validity of the Walter Index in predicting posthospitalization mortality risk in Brazilian older adult inpatients.
J Biomol NMR
January 2025
Department of Chemistry "Ugo Schiff" and Magnetic Resonance Center (CERM), University of Florence, Florence, Italy.
Intrinsically disordered proteins and protein regions are central to many biological processes but difficult to characterize at atomic resolution. Nuclear magnetic resonance is particularly well-suited for providing structural and dynamical information on intrinsically disordered proteins, but existing NMR methodologies need to be constantly refined to provide greater sensitivity and resolution, particularly to capitalise on the potential of high magnetic fields to investigate large proteins. In this paper, we describe how N-detected 2D NMR experiments can be optimised for better performance.
View Article and Find Full Text PDFClin Oral Investig
January 2025
Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany.
Objectives: Information on the oral health of patients with anorexia nervosa remains not satisfactory. The aim of this systematic review is to evaluate oral health parameters in anorexic patients compared to healthy individuals. Furthermore, potential clinical implications for orthodontic treatment are discussed from an orthodontic perspective.
View Article and Find Full Text PDFInt Arch Occup Environ Health
January 2025
Division of Work and Health, Federal Institute for Occupational Safety and Health (BAuA), Nöldnerstr. 40-42, 10317, Berlin, Germany.
Purpose: This study analyzed longitudinal data to examine whether occupational sitting time is associated with increases in body mass index (BMI) and five-year cardiovascular disease (CVD) risk.
Methods: We included 2,000 employed men and women (aged 31-60) from the German Study on Mental Health at Work (S-MGA) for a BMI analysis and 1,635 participants free of CVD at baseline (2011/2012) for a CVD analysis. Occupational sitting time was categorized into five groups (< 5, 5 to < 15, 15 to < 25, 25 to < 35, and ≥ 35 h per week).
Pain
January 2025
Department of Obstetrics and Gynecology, Ribeirão Preto Medical School of the University of São Paulo-USP, Ribeirão Preto, Brazil.
This study aimed to report the incidence of chronic pelvic pain in women 12 to 24 months postpartum, to identify the independently associated factors, and to conduct a causal inference with C-section as the exposure. This was a cross-sectional study nested within 2 distinct prospective cohorts from 2 Brazilian cities. Chronic pelvic pain was the dependent variable.
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