The cell division-independent growth of terminally differentiated cardiomyocytes is commonly associated with cardiovascular disease. We demonstrate that it is accompanied by a substantial rise in transcription by RNA polymerase (pol) III, which produces essential components of the biosynthetic apparatus, including 5S rRNA and tRNAs. This increase in transcription is achieved by changes in both the activity and level of the essential pol III-specific transcription factor TFIIIB. Erk and c-Myc, which directly activate TFIIIB in proliferating fibroblasts, also induce pol III transcription in growing cardiomyocytes. Furthermore, hypertrophic stimulation increases expression of the essential TFIIIB subunit Brf1, an effect not seen when fibroblasts proliferate. Erk mediates this induction of Brf1 expression and therefore contributes in at least two ways to pol III transcriptional activation during hypertrophy. Increased production of tRNA and 5S rRNA will contribute to the enhanced translational capacity required to sustain hypertrophic growth.
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http://dx.doi.org/10.1038/sj.emboj.7601040 | DOI Listing |
elements are primate-specific retrotransposon sequences that comprise ∼11% of human genomic DNA. sequences contain an internal RNA polymerase III promoter and the resultant RNA transcripts mobilize by a replicative process termed retrotransposition. retrotransposition requires the Long INterspersed Element-1 (LINE-1) open reading frame 2-encoded protein (ORF2p).
View Article and Find Full Text PDFChin Med J (Engl)
January 2025
Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, National Clinical Research Center for Obstetric & Gynecologic Diseases, Beijing 100730, China.
Background: Fibrosis of the connective tissue in the vaginal wall predominates in pelvic organ prolapse (POP), which is characterized by excessive fibroblast-to-myofibroblast differentiation and abnormal deposition of the extracellular matrix (ECM). Our study aimed to investigate the effect of ECM stiffness on vaginal fibroblasts and to explore the role of methyltransferase 3 (METTL3) in the development of POP.
Methods: Polyacrylamide hydrogels were applied to create an ECM microenvironment with variable stiffness to evaluate the effects of ECM stiffness on the proliferation, differentiation, and expression of ECM components in vaginal fibroblasts.
J Fungi (Basel)
January 2025
State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
The Cordycipitaceae family of insecticidal fungi is widely distributed in nature, is the most complex in the order Hypocreales (Ascomycota), with members displaying a diversity of morphological characteristics and insect host ranges. Based on Bayesian evolutionary analysis of five genomic loci(the small subunit of ribosomal RNA (SSU) gene, the large subunit of ribosomal RNA (LSU) gene, the translation elongation factor 1-α () gene, the largest subunit of RNA polymerase II (), and the second largest subunit of RNA polymerase II (), we inferred the divergence times for members of the Cordycipitaceae, improving the internal phylogeny of this fungal family. Molecular clock analyses indicate that the ancestor of occurred in the Paleogene period (34.
View Article and Find Full Text PDFObjective: Scleroderma-associated autoantibodies (SSc-Abs) are specific in participants (pts) with systemic sclerosis and are associated with organ involvement. Our objective was to assess the influence of baseline SSc-Abs on the trajectories of the clinical outcome assessments (COAs) in a phase III randomized controlled trial.
Methods: We used data on both the groups who received placebo (Pbo) and tocilizumab from the focuSSced trial.
Sci Rep
January 2025
Emergency department, The Fourth Hospital of Hebei Medical University, Shijiazhuang, 050011, Hebei, China.
Esophageal squamous cell carcinoma (ESCC) is one of the most common digestive malignancies. Our previous studies revealed necroptosis-related lncRNA ENSG00000253385.1 was an independent prognostic factor for ESCC.
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