scholarly journals RNA uridylation and decay in plants

2018 ◽  
Vol 373 (1762) ◽  
pp. 20180163 ◽  
Author(s):  
Caroline de Almeida ◽  
Hélène Scheer ◽  
Anthony Gobert ◽  
Veronica Fileccia ◽  
Federico Martinelli ◽  
...  
Keyword(s):  
Rna Degradation ◽  
Flowering Plant ◽  
Future Research ◽  
Transcriptional Gene Silencing ◽  
Messenger Rnas ◽  
Plant Infection ◽  
Post Transcriptional Gene Silencing ◽  
Key Points ◽  
History Of ◽  
And Function

RNA uridylation consists of the untemplated addition of uridines at the 3′ extremity of an RNA molecule. RNA uridylation is catalysed by terminal uridylyltransferases (TUTases), which form a subgroup of the terminal nucleotidyltransferase family, to which poly(A) polymerases also belong. The key role of RNA uridylation is to regulate RNA degradation in a variety of eukaryotes, including fission yeast, plants and animals. In plants, RNA uridylation has been mostly studied in two model species, the green algaeChlamydomonas reinhardtiiand the flowering plantArabidopsis thaliana. Plant TUTases target a variety of RNA substrates, differing in size and function. These RNA substrates include microRNAs (miRNAs), small interfering silencing RNAs (siRNAs), ribosomal RNAs (rRNAs), messenger RNAs (mRNAs) and mRNA fragments generated during post-transcriptional gene silencing. Viral RNAs can also get uridylated during plant infection. We describe here the evolutionary history of plant TUTases and we summarize the diverse molecular functions of uridylation during RNA degradation processes in plants. We also outline key points of future research.This article is part of the theme issue ‘5′ and 3′ modifications controlling RNA degradation’.

scholarly journals FIERY1 promotes microRNA accumulation by suppressing rRNA-derived small interfering RNAs in Arabidopsis

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Chenjiang You ◽  
Wenrong He ◽  
Runlai Hang ◽  
Cuiju Zhang ◽  
Xiaofeng Cao ◽  
...  
Keyword(s):  
Rna Degradation ◽  
Transcriptional Gene Silencing ◽  
Rrna Processing ◽  
Small Interfering Rnas ◽  
Post Transcriptional Gene Silencing ◽  
Processing Defects ◽  
And Function ◽  
Mirna Abundance ◽  
Unknown Link

Abstract Plant microRNAs (miRNAs) associate with ARGONAUTE1 (AGO1) to direct post-transcriptional gene silencing and regulate numerous biological processes. Although AGO1 predominantly binds miRNAs in vivo, it also associates with endogenous small interfering RNAs (siRNAs). It is unclear whether the miRNA/siRNA balance affects miRNA activities. Here we report that FIERY1 (FRY1), which is involved in 5′−3′ RNA degradation, regulates miRNA abundance and function by suppressing the biogenesis of ribosomal RNA-derived siRNAs (risiRNAs). In mutants of FRY1 and the nuclear 5′−3′ exonuclease genes XRN2 and XRN3, we find that a large number of 21-nt risiRNAs are generated through an endogenous siRNA biogenesis pathway. The production of risiRNAs correlates with pre-rRNA processing defects in these mutants. We also show that these risiRNAs are loaded into AGO1, causing reduced loading of miRNAs. This study reveals a previously unknown link between rRNA processing and miRNA accumulation.

Post-transcriptional gene silencing of ACC synthase in tomato results from cytoplasmic RNA degradation

1997 ◽  
Vol 12 (5) ◽  
pp. 1127-1137 ◽  
Author(s):  
Kathleen Y. Lee ◽  
Catherine Baden ◽  
William J. Howie ◽  
John Bedbrook ◽  
Pamela Dunsmuir
Keyword(s):  
Gene Silencing ◽  
Acc Synthase ◽  
Rna Degradation ◽  
Transcriptional Gene Silencing ◽  
Post Transcriptional Gene Silencing ◽  
Cytoplasmic Rna

Structure and Function of a Chihuahuan Desert Ecosystem

2006 ◽  
Keyword(s):  
Chihuahuan Desert ◽  
Livestock Grazing ◽  
Desert Ecosystem ◽  
Future Research ◽  
Data Sets ◽  
South Central ◽  
Wide Range ◽  
History Of ◽  
Jornada Basin ◽  
And Function

The Jornada Basin LTER is located in the Chihuahuan Desert, the largest in North America. This region of south central New Mexico has a history of nearly 100 years as the basis for scientific research. This work gives a thorough, encompassing review of the tremendous array of observations resulting from experiments conducted in this ecosystem. Beginning with thorough descriptions of the most salient features of the region, the book then reviews a wide range of archived and active data sets on a diversity of biotic and abiotic features. It next presents a syntheses of important topics including livestock grazing and remediation efforts. A concluding chapter provides a synthesis of the principles that have emerged from this body of work, and how these relate to the broader fields of ecology and natural resource management. It concludes with recommendations for future research directions. The insightful views expressed in this volume should guide management of arid landscapes globally. This is the sixth volume in the Long Term Ecological Network Series.

scholarly journals MicroRNAs in the skin: role in development, homoeostasis and regeneration

2017 ◽  
Vol 131 (15) ◽  
pp. 1923-1940 ◽  
Author(s):  
Steven Horsburgh ◽  
Nicola Fullard ◽  
Mathilde Roger ◽  
Abbie Degnan ◽  
Stephen Todryk ◽  
...  
Keyword(s):  
Therapeutic Interventions ◽  
Transcriptional Gene Silencing ◽  
Biological Functions ◽  
Vast Number ◽  
Regulate Gene Expression ◽  
Post Transcriptional Gene Silencing ◽  
Non Coding Rnas ◽  
And Function ◽  
Molecular Signals

The skin is the largest organ of the integumentary system and possesses a vast number of functions. Due to the distinct layers of the skin and the variety of cells which populate each, a tightly regulated network of molecular signals control development and regeneration, whether due to programmed cell termination or injury. MicroRNAs (miRs) are a relatively recent discovery; they are a class of small non-coding RNAs which possess a multitude of biological functions due to their ability to regulate gene expression via post-transcriptional gene silencing. Of interest, is that a plethora of data demonstrates that a number of miRs are highly expressed within the skin, and are evidently key regulators of numerous vital processes to maintain non-aberrant functioning. Recently, miRs have been targeted as therapeutic interventions due to the ability of synthetic ‘antagomiRs’ to down-regulate abnormal miR expression, thereby potentiating wound healing and attenuating fibrotic processes which can contribute to disease such as systemic sclerosis (SSc). This review will provide an introduction to the structure and function of the skin and miR biogenesis, before summarizing the literature pertaining to the role of miRs. Finally, miR therapies will also be discussed, highlighting important future areas of research.

scholarly journals Unique bacterial assembly, composition, and interactions in a parasitic plant and its host

2020 ◽  
Vol 71 (6) ◽  
pp. 2198-2209 ◽  
Author(s):  
Connor R Fitzpatrick ◽  
Adam C Schneider
Keyword(s):  
Host Plant ◽  
Natural Populations ◽  
Parasitic Plant ◽  
Plant Infection ◽  
History Of ◽  
Network Properties ◽  
Plant Microbiota ◽  
And Function ◽  
Root Tissues ◽  
Plant Microbiome

Abstract How plant-associated microbiota are shaped by, and potentially contribute to, the unique ecology and heterotrophic life history of parasitic plants is relatively unknown. Here, we investigate the leaf and root bacterial communities of the root holoparasite Orobanche hederae and its host Hedera spp. from natural populations. Root bacteria inhabiting Orobanche were less diverse, had fewer co-associations, and displayed increased compositional similarity to leaf bacteria relative to Hedera. Overall, Orobanche bacteria exhibited significant congruency with Hedera root bacteria across sites, but not the surrounding soil. Infection had localized and systemic effects on Hedera bacteria, which included effects on the abundance of individual taxa and root network properties. Collectively, our results indicate that the parasitic plant microbiome is derived but distinct from the host plant microbiota, exhibits increased homogenization between shoot and root tissues, and displays far fewer co-associations among individual bacterial members. Host plant infection is accompanied by modest changes of associated microbiota at both local and systemic scales compared with uninfected individuals. Our results are a first step towards extending the growing insight into the assembly and function of the plant microbiome to include the ecologically unique but often overlooked guild of heterotrophic plants.

scholarly journals Distinct expression, localization and function of two Rab7 proteins encoded by paralogous genes in a free-living model eukaryote.

2011 ◽  
Vol 58 (4) ◽  
Author(s):  
Magdalena Osińska ◽  
Jolanta Wiejak ◽  
Emilia Wypych ◽  
Henryk Bilski ◽  
Rafał Bartosiewicz ◽  
...  
Keyword(s):  
Membrane Trafficking ◽  
Pcr Analysis ◽  
Transcriptional Gene Silencing ◽  
Post Translational Modification ◽  
Paralogous Genes ◽  
Post Transcriptional Gene Silencing ◽  
2D Gel ◽  
And Function ◽  
Microtubular Structures ◽  
Confocal And Electron Microscopy

Rab7 GTPases are involved in membrane trafficking in the late endosomal/lysosomal pathway. In Paramecium octaurelia Rab7a and Rab7b are encoded by paralogous genes. Antipeptide antibodies generated against divergent C-termini recognize Rab7a of 22.5 kDa and Rab7b of 25 kDa, respectively. In 2D gel electrophoresis two immunoreactive spots were identified for Rab7b at pI about 6.34 and about 6.18 and only one spot for Rab7a of pI about 6.34 suggesting post-translational modification of Rab7b. Mass spectrometry revealed eight identical phosphorylated residues in the both proteins. ProQ Emerald staining and ConA overlay of immunoprecipitated Rab7b indicated its putative glycosylation that was further supported by a faster electrophoretic mobility of this protein upon deglycosylation. Such a post-translational modification and substitution of Ala(140) in Rab7a for Ser(140) in Rab7b may result in distinct targeting to the oral apparatus where Rab7b associates with the microtubular structures as revealed by STED confocal and electron microscopy. Rab7a was mapped to phagosomal compartment. Absolute qReal-Time PCR analysis revealed that expression of Rab7a was 2.6-fold higher than that of Rab7b. Upon latex internalization it was further 2-fold increased for Rab7a and only slightly for Rab7b. Post-transcriptional gene silencing of rab7a suppressed phagosome formation by 70 % and impaired their acidification. Ultrastructural analysis with double immunogold labeling revealed that this effect was due to the lack of V-ATPase recruitment to phagolysosomes. No significant phenotype changes were noticed in cells upon rab7b silencing. In conclusion, Rab7b acquired a new function, whereas Rab7a can be assigned to the phagolysosomal pathway.

scholarly journals Effects of the Crinivirus Coat Protein–Interacting Plant Protein SAHH on Post-Transcriptional RNA Silencing and Its Suppression

2013 ◽  
Vol 26 (9) ◽  
pp. 1004-1015 ◽  
Author(s):  
M. Carmen Cañizares ◽  
Rosa Lozano-Durán ◽  
Tomás Canto ◽  
Eduardo R. Bejarano ◽  
David M. Bisaro ◽  
...  
Keyword(s):  
Coat Protein ◽  
Rna Silencing ◽  
Rna Degradation ◽  
Plant Viruses ◽  
Plant Protein ◽  
Transcriptional Gene Silencing ◽  
Small Interfering Rnas ◽  
Post Transcriptional Gene Silencing ◽  
Secondary Sirnas ◽  
Tomato Chlorosis Virus

In plants, post-transcriptional gene silencing (PTGS) is a sequence-specific mechanism of RNA degradation induced by double-stranded RNA (dsRNA), which is processed into small interfering RNAs (siRNAs). siRNAs are methylated and, thereby, stabilized by the activity of the S-adenosylmethionine-dependent RNA methyltransferase HEN1. PTGS is amplified by host-encoded RNA-dependent RNA polymerases (RDR), which generate dsRNA that is processed into secondary siRNAs. To counteract this RNA silencing-mediated response of the host, plant viruses express proteins with silencing suppression activity. Here, we report that the coat protein (CP) of crinivirus (family Closteroviridae, genus Crinivirus) Tomato chlorosis virus, a known suppressor of silencing, interacts with S-adenosylhomocysteine hydrolase (SAHH), a plant protein essential for sustaining the methyl cycle and S-adenosylmethionine-dependent methyltransferase activity. Our results show that, by contributing to an increased accumulation of secondary siRNAs generated by the action of RDR6, SAHH enhances local RNA silencing. Although downregulation of SAHH prevents local silencing, it enhances the spread of systemic silencing. Our results also show that SAHH is important in the suppression of local RNA silencing not only by the crinivirus Tomato chlorosis virus CP but also by the multifunctional helper component-proteinase of the potyvirus Potato virus Y.

scholarly journals Nostalgia and Heroism: Theoretical Convergence of Memory, Motivation, and Function

2020 ◽  
Vol 11 ◽  
Author(s):  
Scott T. Allison ◽  
Jeffrey D. Green
Keyword(s):  
Role Models ◽  
Goal Pursuit ◽  
The Self ◽  
Future Research ◽  
History Of ◽  
Heroic Action ◽  
And Function ◽  
Conceptual Relationship ◽  
Cultural Role ◽  
Existential Concerns

This article seeks to develop theoretical convergences between the science of nostalgia and the science of heroism. We take four approaches in forging a conceptual relationship between these two phenomena. First, we examine the definitions of nostalgia and heroism from scholars, laypeople, and across cultures, noting how the history of defining the two phenomena has shaped current conceptualizations. Second, we demonstrate how nostalgic experiences consist of reminiscences about our own personal heroism and about cultural role models and heroes. A review of heroism research, moreover, shows also that our recall of our heroes and of heroism is tinged with nostalgia. Third, we make linkages between heroism and nostalgia research focusing on functions, inspiration, sociality, and motivation. Nostalgia researchers have illuminated the functions of nostalgia implicating the self, existential concerns, goal pursuit, and sociality. Our review shows that heroism researchers invoke similar categories of hero functionality. Finally, we propose three areas of future research that can profit from the merging of nostalgia and heroism science, involving the mechanisms by which (a) heroism can fuel nostalgia, (b) nostalgia can promote heroic action, and (c) wisdom results from nostalgic reverie.

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