The first step in microRNA (miRNA) biogenesis usually involves cleavage at the base of its fold-back precursor. Here, we describe a non-canonical processing mechanism for miRNAs miR319 and miR159 in Arabidopsis thaliana. We found that their biogenesis begins with the cleavage of the loop, instead of the usual cut at the base of the stem-loop structure. DICER-LIKE 1 (DCL1) proceeds then with three additional cuts until the mature miRNA is released. We further show that the conserved upper stem of the miR319 precursor is essential to organize its biogenesis, whereas sequences below the miRNA/miRNA(*) region are dispensable. In addition, the bulges present in the fold-back structure reduce the accumulation of small RNAs other than the miRNA. The biogenesis of miR319 is conserved in the moss Physcomitrella patens, showing that this processing mechanism is ancient. These results provide new insights into the plasticity of small-RNA pathways.
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http://dx.doi.org/10.1038/emboj.2009.292 | DOI Listing |
Environ Sci Technol
January 2025
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Pyrogenic carbons (PCs), with varying structures depending on the materials and thermal treatment conditions, have been extensively used to enhance anaerobic digestion by mediating electron transfer. However, the underlying mechanism has yet to be explored. Herein, the redirection and enhancement of the direct interspecies electron transfer (DIET) pathway were evidenced, along with the upregulated electrochemical properties and structural proteins in the methanogenic consortia.
View Article and Find Full Text PDFClin Rev Allergy Immunol
January 2025
Department of Dermatology and Venereology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
In recent years, epigenetic modifications have attracted significant attention due to their unique regulatory mechanisms and profound biological implications. Acting as a bridge between environmental stimuli and changes in gene activity, they reshape gene expression patterns, providing organisms with regulatory mechanisms to respond to environmental changes. A growing body of evidence indicates that epigenetic regulation plays a crucial role in the pathogenesis and progression of psoriasis.
View Article and Find Full Text PDFAtten Percept Psychophys
January 2025
Department of Psychology, The Ohio State University, 225 Psychology Building, 1835 Neil Ave, Columbus, OH, 43210, USA.
Humans can learn to attentionally suppress salient, irrelevant information when it consistently appears at a predictable location. While this ability confers behavioral benefits by reducing distraction, the full scope of its utility is unknown. As people locomote and/or shift between task contexts, known-to-be-irrelevant locations may change from moment to moment.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Grupo de Investigación Materiales Con Impacto (Mat&Mpac), Facultad de Ciencias Básicas, Universidad de Medellín, Carrera 87 No. 30-65, 050026, Medellín, Colombia.
This study shows the efficiency of WH-C450, an adsorbent obtained from water hyacinth (WH) biomass, in the removal of sulfamethoxazole (SMX) from aqueous solutions. The process involves calcination of WH at 450 °C to produce an optimal adsorbent material capable of removing up to 73% of SMX and maximum SMX adsorption capacity of 132.23 mg/g.
View Article and Find Full Text PDFIn Vitro Cell Dev Biol Anim
January 2025
Department of Oral and Maxillofacial Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, 250012, Shandong, China.
Cleft lip and palate (CL/P) are prevalent congenital anomalies with complex genetic causes. The G874A mutation of T-box transcription factor 22 (TBX-22) gene is notably associated with CL/P, while the underlying mechanism remains to be clarified. Studies have shown that the restriction of epithelial-mesenchymal transformation (EMT) process in medial edge epithelial cells (MEEs) is crucial for CL/P development.
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