The branch site of group II introns is typically a bulged adenosine near the 3'-end of intron domain 6. The branch site is chosen with extraordinarily high fidelity, even when the adenosine is mutated to other bases or if the typically bulged adenosine is paired. Given these facts, it has been difficult to discern the mechanism by which the proper branch site is chosen. In order to dissect the determinants for branch-point recognition, new mutations were introduced in the vicinity of the branch site and surrounding domains. Single mutations did not alter the high fidelity for proper branch-site selection. However, several combinations of mutations moved the branch site systematically to new positions along the domain 6 stem. Analysis of those mutants, together with a new alignment of domain 5 and domain 6 sequences, reveals a set of structural determinants that appear to govern branch-site selection by group II introns.
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http://dx.doi.org/10.1093/emboj/20.23.6866 | DOI Listing |
J Am Med Inform Assoc
January 2025
Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, Philadelphia, PA 19104, United States.
Objective: To develop a distributed algorithm to fit multi-center Cox regression models with time-varying coefficients to facilitate privacy-preserving data integration across multiple health systems.
Materials And Methods: The Cox model with time-varying coefficients relaxes the proportional hazards assumption of the usual Cox model and is particularly useful to model time-to-event outcomes. We proposed a One-shot Distributed Algorithm to fit multi-center Cox regression models with Time varying coefficients (ODACT).
Plants (Basel)
January 2025
College of Agriculture and Plant Immunity Center, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
In rice, leucine-rich repeat nucleotide-binding site (NLR) proteins are pivotal immune receptors in combating -triggered rice blast. However, the precise molecular mechanism underlying how NLR proteins regulate downstream signalling remains elusive due to the lack of knowledge regarding their direct downstream targets. The NLR protein Pigm-1 was cloned from Shuangkang 77009 in our laboratory.
View Article and Find Full Text PDFLife (Basel)
January 2025
School of Environment and Geography, Qingdao University, Qingdao 266071, China.
The potential health risks posed by the coexistence of nanoplastics (NPs) and triclosan (TCS) have garnered significant attention. However, the effects and underlying mechanisms of NPs and TCS on key functional proteins at the molecular level remain poorly understood. This study reports the effect of polystyrene nanoplastics (PSNPs) on the binding of TCS to human serum albumin (HSA) using multispectral methods and molecular simulation systems.
View Article and Find Full Text PDFInsects
January 2025
Program in Ecology and Environmental Science and Large River Studies Center, Department of Biology, Winona State University, Winona, MN 55987, USA.
Prior to implementing watershed-wide projects to reduce the impacts of agriculture on regional streams and rivers, stream habitats and benthic aquatic macroinvertebrate communities were assessed at 15 sites on the South Branch Root River and its major tributaries in southeastern Minnesota, USA. Triplicate kick-net samples were collected from each site during three time periods (1998, 1999, 2006/2008) and stream habitats were inventoried within 150 m long sections at each site. In total, 26,760 invertebrates representing 84 taxa were collected and used to rate stream sites using a regional multi-metric benthic index of biotic integrity (BIBI).
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Siberian Branch of the Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Ave., 630090 Novosibirsk, Russia.
The apurinic/apyrimidinic site (AP site) is a highly mutagenic and cytotoxic DNA lesion. Normally, AP sites are removed from DNA by base excision repair (BER). Methoxyamine (MOX), a BER inhibitor currently under clinical trials as a tumor sensitizer, forms adducts with AP sites (AP-MOX) resistant to the key BER enzyme, AP endonuclease.
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