Discovery of Small Regulatory RNAs Extends Our Understanding of Gene Regulation in the Acidithiobacillus Genus

Author(s):  
Amir Shmaryahu ◽  
David S. Holmes
Author(s):  
Zhi-Qiang Xiong ◽  
Ze-Xuan Lv ◽  
Xin Song ◽  
Xin-Xin Liu ◽  
Yong-Jun Xia ◽  
...  

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 267
Author(s):  
Axel J. Giudicatti ◽  
Ariel H. Tomassi ◽  
Pablo A. Manavella ◽  
Agustin L. Arce

MicroRNAs are small regulatory RNAs involved in several processes in plants ranging from development and stress responses to defense against pathogens. In order to accomplish their molecular functions, miRNAs are methylated and loaded into one ARGONAUTE (AGO) protein, commonly known as AGO1, to stabilize and protect the molecule and to assemble a functional RNA-induced silencing complex (RISC). A specific machinery controls miRNA turnover to ensure the silencing release of targeted-genes in given circumstances. The trimming and tailing of miRNAs are fundamental modifications related to their turnover and, hence, to their action. In order to gain a better understanding of these modifications, we analyzed Arabidopsis thaliana small RNA sequencing data from a diversity of mutants, related to miRNA biogenesis, action, and turnover, and from different cellular fractions and immunoprecipitations. Besides confirming the effects of known players in these pathways, we found increased trimming and tailing in miRNA biogenesis mutants. More importantly, our analysis allowed us to reveal the importance of ARGONAUTE 1 (AGO1) loading, slicing activity, and cellular localization in trimming and tailing of miRNAs.


Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 118
Author(s):  
Arsala Ali ◽  
Kyudong Han ◽  
Ping Liang

Transposable elements (TEs), also known as mobile elements (MEs), are interspersed repeats that constitute a major fraction of the genomes of higher organisms. As one of their important functional impacts on gene function and genome evolution, TEs participate in regulating the expression of genes nearby and even far away at transcriptional and post-transcriptional levels. There are two known principal ways by which TEs regulate the expression of genes. First, TEs provide cis-regulatory sequences in the genome with their intrinsic regulatory properties for their own expression, making them potential factors for regulating the expression of the host genes. TE-derived cis-regulatory sites are found in promoter and enhancer elements, providing binding sites for a wide range of trans-acting factors. Second, TEs encode for regulatory RNAs with their sequences showed to be present in a substantial fraction of miRNAs and long non-coding RNAs (lncRNAs), indicating the TE origin of these RNAs. Furthermore, TEs sequences were found to be critical for regulatory functions of these RNAs, including binding to the target mRNA. TEs thus provide crucial regulatory roles by being part of cis-regulatory and regulatory RNA sequences. Moreover, both TE-derived cis-regulatory sequences and TE-derived regulatory RNAs have been implicated in providing evolutionary novelty to gene regulation. These TE-derived regulatory mechanisms also tend to function in a tissue-specific fashion. In this review, we aim to comprehensively cover the studies regarding these two aspects of TE-mediated gene regulation, mainly focusing on the mechanisms, contribution of different types of TEs, differential roles among tissue types, and lineage-specificity, based on data mostly in humans.


2007 ◽  
Vol 2 (6) ◽  
pp. 519-521 ◽  
Author(s):  
Fabio T.S. Nogueira ◽  
Marja C.P. Timmermans

2018 ◽  
Author(s):  
Taylor B Updegrove ◽  
Andrew B Kouse ◽  
Katarzyna J Bandyra ◽  
Gisela Storz

AbstractIncreasing numbers of 3′UTR-derived small, regulatory RNAs (sRNAs) are being discovered in bacteria, most generated by cleavage from longer transcripts. The enzyme required for these cleavages has been reported to be RNase E, the major endoribonuclease in enterica bacteria. Previous studies investigating RNase E have come to a range of different conclusions regarding the determinants for RNase E processing. To understand the sequence and structure determinants for the precise processing of the 3′ UTR-derived sRNAs, we examined the cleavage of multiple mutant and chimeric derivatives of the 3′ UTR-derived MicL sRNA in vivo and in vitro. Our results revealed that tandem stem-loops 3′ to the cleavage site define optimal, correctly-positioned cleavage of MicL and likely other similar sRNAs. Moreover, our assays of MicL, ArcZ and CpxQ showed that sRNAs exhibit differential sensitivity to RNase E, likely a consequence of a hierarchy of sRNA features recognized by the endonuclease.


2016 ◽  
Vol 75 (1) ◽  
pp. ftw113 ◽  
Author(s):  
Shantanu Bhatt ◽  
Marisa Egan ◽  
Jasmine Ramirez ◽  
Christian Xander ◽  
Valerie Jenkins ◽  
...  

2019 ◽  
Vol 3 (1) ◽  
pp. 01-02
Author(s):  
Shao Ying

MicroRNAs (miRNAs) are short single-stranded noncoding RNAs (20- to 25-nucleotide (nt) long) representing a class of small regulatory RNAs. By inhibiting the translation of target mRNAs, miRNAs regulate gene expression posttranscriptionally and thus play an important role in a wide range of cellular processes. Currently, there are two known types of miRNAs: intergenic and intronic miRNAs. Biogenesis of an intergenic miRNA starts with the synthesis of a primary miRNA transcript (pri-miRNA) catalyzed by types-II or -III RNA polymerase (Pol-II/III). Pri-miRNAs are processed in the nucleus by the ribonuclease Drosha into a miRNA precursor (pre-miRNA) approximately 60-nt in length. After being transported into the cytoplasm, these pre-miRNAs are further processed into mature and functional miRNAs by the cytoplasmic ribonuclease Dicer. Mature miRNAs then associate with a number of proteins to form the RNA-induced silencing complex (RISC) that bind with target mRNAs having total or partial complementary sequences to the miRNAs and initiate the inhibition of subsequent protein translation via RNA interference (RNAi).


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