scholarly journals Non-Templated Oligo-Adenylation of Small RNAs in the Parasite Entamoeba: Potential Roles for Small RNA Control in Single Celled Eukaryotic Pathogen

2020 ◽  
Author(s):  
Hanbang Zhang ◽  
Gretchen M Ehrenkaufer ◽  
Neil Hall ◽  
Upinder Singh
Keyword(s):  
Small Rna ◽  
Small Rnas ◽  
Cellular Localization ◽  
High Throughput Sequencing ◽  
Target Genes ◽  
Protozoan Parasite ◽  
Rnai Pathway ◽  
Regulation Mechanism ◽  
Protozoan Parasites ◽  
Modification Process

Abstract Background: The RNA interference (RNAi) pathway is a gene regulation mechanism that uitilizes small RNA (sRNA) and Argonaute (Ago) proteins to silence target genes. Our previous work identified a functional RNAi pathway in the protozoan parasite Entamoeba histolytica, including abundant 27nt antisense sRNA populations derived from the secondary RNAi pathway which associate with EhAgo2-2 protein. However, there is lack of understanding about sRNAs that are bound to two other EhAgos (EhAgo2-1 and 2-3), and the mechanism of sRNA regulation itself is unclear in this parasite. Results: In the present study, we sequenced sRNA libraries from both total RNAs and EhAgo bound RNAs. We identified a new population of 31nt sRNAs that results from the addition of a non-templated 3-4 adenosine nucleotides at the 3´-end of the 27nt sRNA populations, indicating a non-templated RNA-tailing event in the parasite. We found that both sRNA populations (27nt and 31nt) are unchanged during the development of E. invadens. However, we detected an alteration in their relative abundance for the targeted gene in parasites transfected with a trigger-gene silencing construct, indicating that non-templated RNA-tailing is likely a pathway for sRNA turnover when the targeted gene is unable to be silenced in this parasite. In sequencing the sRNAs associating with the three EhAgo proteins, we observed that despite distinct cellular localization, all three EhAgo sRNA libraries contain 27nt sRNAs with 5´-polyphosphate (5´-polyP) structure and a largely overlapping sRNA repertoire, mainly targeting retrotransposons and a subset of ~226 genes that are endogenously silenced. Furthermore, our data show that 31nt sRNA populations paritally associate with wildtype EhAgo2-2 but not with its mutant protein (EhAgo2-2 C-terminal deletion), indicating an intact RISC is essential for the sRNA modification process.Conclusion: High-throughput sequencing of sRNA in Entamoeba has identified a new population of sRNA with non-templated adenylation modification, which is the first such observation amongst single cell protozoan parasites. Our sRNA sequencing libraries provide the first comprehensive sRNA dataset for all three Entamoeba Ago proteins, which can serve as a useful database for the amoeba community.

scholarly journals Identification of oligo-adenylated small RNAs in the parasite Entamoeba and a potential role for small RNA control

BMC Genomics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Hanbang Zhang ◽  
Gretchen M. Ehrenkaufer ◽  
Neil Hall ◽  
Upinder Singh
Keyword(s):  
Small Rna ◽  
Cellular Localization ◽  
Potential Role ◽  
Target Genes ◽  
Protozoan Parasite ◽  
Rnai Pathway ◽  
Regulation Mechanism ◽  
Major Step ◽  
Entamoeba Invadens ◽  
Related Parasite

Abstract Background The RNA interference (RNAi) pathway is a gene regulation mechanism that utilizes small RNA (sRNA) and Argonaute (Ago) proteins to silence target genes. Our previous work identified a functional RNAi pathway in the protozoan parasite Entamoeba histolytica, including abundant 27 nt antisense sRNA populations which associate with EhAgo2–2 protein. However, there is lack of understanding about the sRNAs that are bound to two other EhAgos (EhAgo2–1 and 2–3), and the mechanism of sRNA regulation itself is unclear in this parasite. Therefore, identification of the entire pool of sRNA species and their sub-populations that associate with each individual EhAgo protein would be a major step forward. Results In the present study, we sequenced sRNA libraries from both total RNAs and EhAgo bound RNAs. We identified a new population of 31 nt sRNAs that results from the addition of a non-templated 3–4 adenosine nucleotides at the 3′-end of the 27 nt sRNAs, indicating a non-templated RNA-tailing event in the parasite. The relative abundance of these two sRNA populations is linked to the efficacy of gene silencing for the target gene when parasites are transfected with an RNAi-trigger construct, indicating that non-templated sRNA-tailing likely play a role in sRNA regulation in this parasite. We found that both sRNA populations (27 nt and 31 nt) are present in the related parasite Entamoeba invadens, and are unchanged during the development. In sequencing the sRNAs associating with the three EhAgo proteins, we observed that despite distinct cellular localization, all three EhAgo sRNA libraries contain 27 nt sRNAs with 5′-polyphosphate (5′-polyP) structure and share a largely overlapping sRNA repertoire. In addition, our data showed that a fraction of 31 nt sRNAs associate with EhAgo2–2 but not with its mutant protein (C-terminal deletion), nor other two EhAgos, indicating a specific EhAgo site may be required for sRNA modification process in the parasite. Conclusion We identified a new population of sRNA with non-templated oligo-adenylation modification, which is the first such observation amongst single celled protozoan parasites. Our sRNA sequencing libraries provide the first comprehensive sRNA dataset for all three Entamoeba Ago proteins, which can serve as a useful database for the amoeba community.

Dysregulation of tRNA-derived small RNAs and their potential roles in lupus nephritis

Lupus ◽  
2021 ◽  
pp. 096120332110614
Author(s):  
Yan Liang ◽  
Ji Zhang ◽  
Wenxian Qiu ◽  
Bo Chen ◽  
Ying Zhou ◽  
...  
Keyword(s):  
Lupus Nephritis ◽  
Signaling Pathway ◽  
Small Rnas ◽  
High Throughput Sequencing ◽  
Target Genes ◽  
Expression Profiles ◽  
Mapk Signaling ◽  
Pcr Analysis ◽  
Clinical Indicators ◽  
Qrt Pcr

Objective Lupus nephritis (LN) is a major end-organ complication of systemic lupus erythematosus (SLE), and the molecular mechanism of LN is not completely clear. Accumulating pieces of evidence indicate the potential vital role of tRNA-derived small RNAs (tsRNAs) in human diseases. Current study aimed to investigate the potential roles of tsRNAs in LN. Methods We herein employed high‐throughput sequencing to screen the expression profiles of tsRNAs in renal tissues of the LN and control groups. To validate the sequencing data, we performed quantitative real-time PCR (qRT-PCR) analysis. Correlational analysis of verified tsRNAs expression and clinical indicators was conducted using linear regression. The potential target genes were also predicted. The biological functions of tsRNAs were annotated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Results Our findings revealed that the expression profiles of tsRNAs were significantly altered in the kidney tissues from LN patients compared with control. Overall, 160 tsRNAs were significantly dysregulated in the LN group, of which 79 were upregulated, whereas 81 were downregulated. Subsequent qRT-PCR results confirmed the different expression of candidate tsRNAs. Correlation analysis results found that expression of verified tsRNAs were correlated to clinical indicators. The target prediction results revealed that verified tsRNAs might act on 712 target genes. Further bioinformatics analysis uncovered tsRNAs might participate in the pathogenesis of LN through several associated pathways, including cell adhesion molecules, MAPK signaling pathway, PI3K-Akt signaling pathway and B cell receptor signaling pathway. Conclusion This study provides a novel insight for studying the mechanism of LN.

scholarly journals Analysis of miRNAs in the Heads of Different Castes of the Bumblebee Bombus lantschouensis (Hymenoptera: Apidae)

Insects ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 349 ◽  
Author(s):  
Liu ◽  
Huang ◽  
Zhang ◽  
Liu ◽  
An
Keyword(s):  
Small Rna ◽  
Small Rnas ◽  
Target Genes ◽  
Solexa Sequencing ◽  
Biological Functions ◽  
Putative Target ◽  
Differentially Expressed Mirnas ◽  
Rna Deep Sequencing ◽  
Small Rna Deep Sequencing ◽  
Go Terms

Bumblebees are important insect pollinators for many wildflowers and crops. MicroRNAs (miRNAs) are endogenous non-coding small RNAs that regulate different biological functions in insects. In this study, the miRNAs in the heads of the three castes of the bumblebee Bombus lantschouensis were identified and characterized by small RNA deep sequencing. The significant differences in the expression of miRNAs and their target genes were analyzed. The results showed that the length of the small RNA reads from males, queens, and workers was distributed between 18 and 30 nt, with a peak at 22 nt. A total of 364 known and 89 novel miRNAs were identified from the heads of the three castes. The eight miRNAs with the highest expressed levels in males, queens, and workers were identical, although the order of these miRNAs based on expression differed. The male vs. queen, male vs. worker, and worker vs. queen comparisons identified nine, fourteen, and four miRNAs with significant differences in expression, respectively. The different castes were clustered based on the differentially expressed miRNAs (DE miRNAs), and the expression levels of the DE miRNAs obtained by RT-qPCR were consistent with the read counts obtained through Solexa sequencing. The putative target genes of these DE miRNAs were enriched in 29 Gene Ontology (GO) terms, and catalytic activity was the most enriched GO term, as demonstrated by its association with 2837 target genes in the male vs. queen comparison, 3535 target genes in the male vs. worker comparison, and 2185 target genes in the worker vs. queen comparison. This study highlights the characteristics of the miRNAs in the three B. lantschouensis castes and will aid further studies on the functions of miRNAs in bumblebees.

scholarly journals Small RNAs in parasitic nematodes – forms and functions

Parasitology ◽  
2019 ◽  
Vol 147 (8) ◽  
pp. 855-864
Author(s):  
Collette Britton ◽  
Roz Laing ◽  
Eileen Devaney
Keyword(s):  
Gene Expression ◽  
Small Rna ◽  
Small Rnas ◽  
Target Genes ◽  
Parasitic Nematodes ◽  
Small Rna Sequencing ◽  
Small Interfering Rnas ◽  
Rna Sequences ◽  
C Elegans

AbstractSmall RNAs are important regulators of gene expression. They were first identified in Caenorhabditis elegans, but it is now apparent that the main small RNA silencing pathways are functionally conserved across diverse organisms. Availability of genome data for an increasing number of parasitic nematodes has enabled bioinformatic identification of small RNA sequences. Expression of these in different lifecycle stages is revealed by small RNA sequencing and microarray analysis. In this review we describe what is known of the three main small RNA classes in parasitic nematodes – microRNAs (miRNAs), Piwi-interacting RNAs (piRNAs) and small interfering RNAs (siRNAs) – and their proposed functions. miRNAs regulate development in C. elegans and the temporal expression of parasitic nematode miRNAs suggest modulation of target gene levels as parasites develop within the host. miRNAs are also present in extracellular vesicles released by nematodes in vitro, and in plasma from infected hosts, suggesting potential regulation of host gene expression. Roles of piRNAs and siRNAs in suppressing target genes, including transposable elements, are also reviewed. Recent successes in RNAi-mediated gene silencing, and application of small RNA inhibitors and mimics will continue to advance understanding of small RNA functions within the parasite and at the host–parasite interface.

scholarly journals Identification of MicroRNAs That Respond to Soybean Cyst Nematode Infection in Early Stages in Resistant and Susceptible Soybean Cultivars

2019 ◽  
Vol 20 (22) ◽  
pp. 5634 ◽  
Author(s):  
Piao Lei ◽  
Bing Han ◽  
Yuanyuan Wang ◽  
Xiaofeng Zhu ◽  
Yuanhu Xuan ◽  
...  
Keyword(s):  
Small Rna ◽  
Soybean Cyst Nematode ◽  
High Throughput Sequencing ◽  
Target Genes ◽  
Cyst Nematode ◽  
Differentially Expressed ◽  
Early Stages ◽  
Differentially Expressed Mirnas ◽  
Plant Pathogen Interactions ◽  
Insight Into

Soybean cyst nematode (SCN) causes heavy losses to soybean yield. In order to investigate the roles of soybean miRNAs during the early stages of infection (1 and 5 dpi), 24 small RNA libraries were constructed from SCN resistant cultivar Huipizhi (HPZ) and the susceptible Williams 82 (W82) cultivar for high-throughput sequencing. By sequencing the small RNA libraries, a total of 634 known miRNAs were identified, and 252 novel miRNAs were predicted. Altogether, 14 known miRNAs belonging to 13 families, and 26 novel miRNAs were differentially expressed and may respond to SCN infection in HPZ and W82. Similar expression results were also confirmed by qRT-PCR. Further analysis of the biological processes that these potential target genes of differentially expressed miRNAs regulate found that they may be strongly related to plant–pathogen interactions. Overall, soybean miRNAs experience profound changes in early stages of SCN infection in both HPZ and W82. The findings of this study can provide insight into miRNAome changes in both HPZ and W82 at the early stages of infection, and may provide a stepping stone for future SCN management.

scholarly journals Comparative profiling of small RNAs of pig seminal plasma and ejaculated and epididymal sperm

Reproduction ◽  
2017 ◽  
Vol 153 (6) ◽  
pp. 785-796 ◽  
Author(s):  
Cai Chen ◽  
Han Wu ◽  
Dan Shen ◽  
Saisai Wang ◽  
Li Zhang ◽  
...  
Keyword(s):  
Seminal Plasma ◽  
Small Rna ◽  
Small Rnas ◽  
Target Genes ◽  
Large Population ◽  
Small Nuclear Rna ◽  
Epididymal Sperm ◽  
Zygote Development ◽  
Similarities And Differences ◽  
Small Rna Species

The similarities and differences of small RNAs in seminal plasma, epididymal sperm and ejaculated sperm remain largely undefined. We conducted a systematic comparative analysis of small RNA profiles in pig ejaculated sperm, epididymal sperm and seminal plasma and found that the diversity distribution of small RNA species was generally similar, whereas the abundance of small RNAs is dramatically different across the three libraries; miRNAs and small RNAs derived from rRNA, tRNA, small nuclear RNA, 7SK RNA, NRON RNA and cis-regulatory RNA were enriched in the three libraries, but piRNA was absent. A large population of small RNAs from ejaculated sperm are ejaculated sperm specific, and only 8–30% of small RNAs overlapped with those of epididymal sperm or seminal plasma and a small proportion (5–18%) of small RNAs were shared in the three libraries, suggesting that, in addition to the testes, sperm RNAs may also originate from seminal plasma, epididymis as well as other resources. Most miRNAs were co-distributed but differentially expressed across the three libraries, with epididymal sperm exhibiting the highest abundance, followed by ejaculated sperm and seminal plasma. The prediction of target genes of the top 10 highly expressed miRNAs across the three libraries revealed that these miRNAs may be involved in spermatogenesis, zygote development and the interaction between the environment and animals. Our study provides the first description of the similarities and differences of small RNA profiles in ejaculated sperm, epididymal sperm and seminal plasma and indicates that sperm RNA may have origins other than the testes.

scholarly journals Different classes of small RNAs are essential for head regeneration in the planarian Dugesia japonica

BMC Genomics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Zhonghong Cao ◽  
David Rosenkranz ◽  
Suge Wu ◽  
Hongjin Liu ◽  
Qiuxiang Pang ◽  
...  
Keyword(s):  
Small Rna ◽  
Small Rnas ◽  
High Throughput Sequencing ◽  
Expression Profiles ◽  
Evolutionary Conservation ◽  
Body Parts ◽  
Promising Candidate ◽  
Dugesia Japonica ◽  
Head Regeneration

Abstract Background Planarians reliably regenerate all body parts after injury, including a fully functional head and central nervous system. But until now, the expression dynamics and functional role of miRNAs and other small RNAs during the process of head regeneration are not well understood. Furthermore, little is known about the evolutionary conservation of the relevant small RNAs pathways, rendering it difficult to assess whether insights from planarians will apply to other taxa. Results In this study, we applied high throughput sequencing to identify miRNAs, tRNA fragments and piRNAs that are dynamically expressed during head regeneration in Dugesia japonica. We further show that knockdown of selected small RNAs, including three novel Dugesia-specific miRNAs, during head regeneration induces severe defects including abnormally small-sized eyes, cyclopia and complete absence of eyes. Conclusions Our findings suggest that a complex pool of small RNAs takes part in the process of head regeneration in Dugesia japonica and provide novel insights into global small RNA expression profiles and expression changes in response to head amputation. Our study reveals the evolutionary conserved role of miR-124 and brings further promising candidate small RNAs into play that might unveil new avenues for inducing restorative programs in non-regenerative organisms via small RNA mimics based therapies.

scholarly journals Circulating tRNA-derived small RNAs (tsRNAs) signature for the diagnosis and prognosis of breast cancer

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Jingyi Wang ◽  
Ge Ma ◽  
Han Ge ◽  
Xu Han ◽  
Xinrui Mao ◽  
...  
Keyword(s):  
Breast Cancer ◽  
High Throughput ◽  
Liquid Biopsy ◽  
Small Rnas ◽  
High Throughput Sequencing ◽  
Target Genes ◽  
Prognostic Biomarkers ◽  
Healthy Controls ◽  
Diagnostic Biomarkers ◽  
Diagnosis And Prognosis

AbstractLiquid biopsy is noninvasive and convenient to detect cancer-derived materials in blood or other body fluids. The aim of this study was to identify tRNA-derived small RNAs (tsRNAs) in plasma that could distinguish patients with breast cancer (BC) from healthy controls. Basing on high-throughput sequencing, 15 significantly upregulated tsRNAs were selected and assessed in cell supernatants and cell lines. 6 tsRNAs were identified and verified in a large cohort of 120 patients with BC and 112 healthy controls. tRF-Arg-CCT-017, tRF-Gly-CCC-001, and tiRNA-Phe-GAA-003 could serve as novel diagnostic biomarkers. Meanwhile, tRF-Arg-CCT-017 and tiRNA-Phe-GAA-003 could also act as prognostic biomarkers. Target genes of these tsRNAs were related to the development of cancers. These results suggested that specific tsRNAs in plasma might serve as diagnostic and prognostic biomarkers of BC.

scholarly journals High-throughput small RNA and transcriptome sequencing reveal reproduction-related microRNAs and mRNA in ovary of Geese in Counter-Season Production

2019 ◽  
Author(s):  
Jin-Shan Ran ◽  
Ling-Qian Yin ◽  
Jing-Jing Li ◽  
Yan-Qiang Tang ◽  
Jian Huang ◽  
...  
Keyword(s):  
High Throughput ◽  
High Throughput Sequencing ◽  
Target Genes ◽  
Mirna Gene ◽  
Egg Laying ◽  
Differentially Expressed ◽  
Ovary Development ◽  
Regulation Mechanism ◽  
Pathway Network ◽  
Apoptosis Pathways

Abstract Background Broodiness is a phenomenon that occurs in most avian species and significantly reduces productivity. Several genes are known to play an important role in regulating the progress of reproduction, but the molecular regulation mechanism of broodiness remains unclear. In the current study, via high throughput sequencing, we identified and explored the differentially expressed miRNAs and mRNAs involved in ovarian atrophy. Results We identified a total of 901 mRNAs and 50 miRNAs that were differentially expressed in egg-laying and atrophic ovaries. Among them, numerous DEGs transcripts and target genes for miRNAs were significantly enriched in reproductive processes, cell proliferation, and apoptosis pathways. In addition, a miRNA- gene-pathway network was constructed by considering target relationships and correlation of the expression levels between ovary development-related genes and miRNAs. Conclusions We discovered mRNA and miRNAs transcripts that are candidate regulators of ovary development in broody geese. Our findings expanded our understanding of the functional of miRNAs in ovarian atrophy and demonstrated that RNA-Seq is a powerful tool for examining the molecular mechanism in regulating broodiness.

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