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The miR390-derived TAS3 trans-acting short-interfering RNAs (tasiRNAs) module represents a conserved RNA silencing pathway in the plant kingdom; however, its characterization in the bryophyte Marchantia polymorpha is limited. This study elucidated that MpDCL4 processes Mp TAS3 double-stranded RNA (dsRNA) to generate tasiRNAs, primarily from the 5ʹ- and 3ʹ-ends of dsRNA. Notably, we discovered a novel tasiRNA, tasi78A, which can negatively regulate a cytochrome P450 gene, Mp CYP78A101. Additionally, tasi78A was abundant in MpAGO1, and transient expression assays underscored the role of tasi78A in repressing Mp CYP78A101. A microRNA, miR11700, also regulates Mp CYP78A101 expression. This coordinate regulation suggests a role in modulating auxin signaling at apical notches of gemma, influencing the growth and sexual organ development of M. polymorpha and emphasizing the significance of RNA silencing in Mp CYP78A101 regulation. However, phylogenetic analysis identified another paralog of the CYP78 family, Mp1g14150, which may have a redundant role with Mp CYP78A101 , explaining the absence of noticeable morphological changes in loss-of-function plants. Taken together, our findings provide new insights into the combined regulatory roles of miR390/Mp TAS3 /miR11700 in controlling Mp CYP78A101 and expand our knowledge about the biogenesis and regulation of tasiRNAs in M. polymorpha. [ABSTRACT FROM AUTHOR]

The higher the enrichment factor, the more significant the enrichment of the differential proteins in the pathway Bioinformatics analysis of the gene expression profile of retinal pigmental epithelial cells based in single-cell RNA sequencing in myopic mice Arch Med Sci 2, February / 2021 577 tration of kynurenic acid transiently increases. Through the single-cell RNA sequencing of the RPE cells, it was found that the cells were exposed to hypoxia during the development of myopia and that hypoxia might lead to functional limitations in the RPE cells [8]. Thus, it can be inferred that RPE cells are exposed to hypoxia during myopia; as RPE cells are oxygen-consuming cells, this hypoxia may activate glycolysis and oxidative phosphorylation in the cells [10-12]. [Extracted from the article]

As a model plant for bryophytes, Marchantia polymorpha offers insights into the role of RNA silencing in aiding early land plants navigate the challenges posed by high-temperature environments. Genomic analysis revealed unique ARGONAUTE1 ortholog gene (MpAGO1) in M. polymorpha that is regulated by two species-specific microRNAs (miRNAs), miR11707.1 and miR11707.2. Comparative studies of small RNA profiles from M. polymorpha cellular and MpAGO1 immunoprecipitation (MpAGO1-IP) profiles at various temperatures, along with analyses of Arabidopsis AGO1 (AtAGO1), revealed that MpAGO1 has a low-selectivity for a diverse range of small RNA species than AtAGO1. Protein structural comparisons revealed no discernible differences in the MID domains of MpAGO1 and AtAGO1, suggesting the complexity of miRNA species specificity and necessitating further exploration. Small RNA profiling and size exclusion chromatography have pinpointed a subset of M. polymorpha miRNAs, notably miR11707, that remain in free form within the cell at 22°C but are loaded into MpAGO1 at 28°C to engage in RNA silencing. Investigations into the mir11707 gene editing (mir11707ge) mutants provided evidence of the regulation of miR11707 in MpAGO1. Notably, while MpAGO1 mRNA expression decreases at 28°C, the stability of the MpAGO1 protein and its associated miRNAs is essential for enhancing the RISC activity, revealing the importance of RNA silencing in enabling M. polymorpha to survive thermal stress. This study advances our understanding of RNA silencing in bryophytes and provides groundbreaking insights into the evolutionary resilience of land plants to climatic adversities., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site–for further information please contact journals.permissions@oup.com.)