Cross-kingdom Regulation Research Articles

In-depth investigation of microRNA-mediated cross-kingdom regulation between Asian honey bee and microsporidian.

Asian honey bee Apis cerana is the original host for Nosema ceranae, a unicellular fungal parasite that causes bee nosemosis throughout the world. Currently, interaction between A. cerana and N. ceranae is largely unknown. Our group previously prepared A. c. cerana workers’ midguts at 7 days post inoculation (dpi) and 10 dpi with N. ceranae spores as well as corresponding un-inoculated workers’ midguts, followed by cDNA library construction and a combination of RNAs-seq and small RNA-seq. Meanwhile, we previously prepared clean spores of N. ceranae, which were then subjected to cDNA library construction and deep sequencing. Here, based on the gained high-quality transcriptome datasets, N. ceranae differentially expressed mRNAs (DEmiRNAs) targeted by host DEmiRNAs, and A. c. cerana DEmRNAs targeted by microsporidian DEmiRNAs were deeply investigated, with a focus on targets involved in N. ceranae glycolysis/glyconeogenesis as well as virulence factors, and A. c. cerana energy metabolism and immune response. In A. c. cerana worker’s midguts at 7 (10) dpi (days post inoculation), eight (seven) up-regulated and six (two) down-regulated miRNAs were observed to target 97 (44) down-regulated and 60 (15) up-regulated N. ceranae mRNAs, respectively. Additionally, two up-regulated miRNAs (miR-60-y and miR-676-y) in host midgut at 7 dpi could target genes engaged in N. ceranae spore wall protein and glycolysis/gluconeogenesis, indicating potential host miRNA-mediated regulation of microsporidian virulence factor and energy metabolism. Meanwhile, in N. ceranae at 7 (10) dpi, 121 (110) up-regulated and 112 (104) down-regulated miRNAs were found to, respectively, target 343 (247) down-regulated and 138 (110) down-regulated mRNAs in A. c. cerana workers’ midguts. These targets in host were relevant to several crucial cellular and humoral immune pathways, such as phagasome, endocytosis, lysosomes, regulation of autophagy, and Jak–STAT signaling pathway, indicative of the involvement of N. ceranae DEmiRNAs in regulating these cellular and humoral immune pathways. In addition, N. ceranae miR-21-x was up-regulated at 7 dpi and had a target relative to oxidative phosphorylation, suggesting that miR-21-x may be used as a weapon to modulate this pivotal energy metabolism pathway. Furthermore, potential targeting relationships between two pairs of host DEmiRNAs-microsporidian DEmRNAs and two pairs of microsporidian DEmiRNAs-host DEmRNAs were validated using RT-qPCR. Our findings not only lay a foundation for exploring the molecular mechanism underlying cross-kingdom regulation between A. c. cerana workers and N. ceranae, but also offer valuable insights into Asian honey bee-microsporidian interaction.

Symbiodiniaceae microRNAs and their targeting sites in coral holobionts: A transcriptomics-based exploration

Corals should make excellent models for cross-kingdom research because of their natural animal-photobiont holobiont composition, yet a lack of studies and experimental data restricts their use. Here we integrate new full-length transcriptomes and small RNAs of four common reef-building corals with the published Cladocopium genomes to gain deeper insight into gene regulation in coral-Symbiodiniaceae holobionts. Eleven novel Symbiodiniaceae miRNAs get identified, and enrichment results of their target genes show that they might play a role in downregulating rejection from host coral cells, protecting symbiont from autophagy and apoptosis in parallel. This work provides evidence for the early origin of cross-kingdom regulation as a mechanism of self-defense autotrophs can use against heterotrophs, sheds more light on coral-Symbiodiniaceae holobionts, and contributes valuable data for further coral research.

Circulating exosome miRNA, is it the novel nutrient molecule through cross-kingdom regulation mediated by food chain transmission from microalgae to bivalve?

MicroRNAs (miRNAs) can efficiently regulate gene expression at intracellular and extracellular levels. Plant-derived miRNAs are highly enriched in animal haemolymph and regulate mammalian gene expression. However, evidence for food-derived miRNAs in Mollusca species is lacking. In this study, we fed the microalga Nannochloropsis oculata to the pearl oyster Pinctada fucata martensii and detected dietary miRNAs in exosomes isolated from the haemolymph by RNA-seq. In total, 273 endogenous miRNAs were identified in all biological replicates. We identified 23 microalgae-derived miRNAs in the exosomes of pearl oyster haemolymph. Most microalgae-derived miRNAs showed high expression levels in both exosomes and microalgae and exhibited apparent variation among individuals. These food-derived miRNAs were predicted to participate in endocytosis, apoptosis, signal transduction, energy metabolism, and biomineralization by targeting multiple genes. These findings demonstrated the cross-kingdom transport of miRNAs from microalgae to bivalves and provide insights into novel nutrient transmission through the food chain.

The Anti-Inflammatory Effect of Cabbage Leaves Explained by the Influence of bol-miRNA172a on FAN Expression.

Recently, the possibility of cross-kingdom gene expression regulation by miRNAs from other species (“xenomiRs”), specifically from plants, has acquired scientific meaning. Based on the one of oldest methods for dealing with inflammation via the use of cabbage leaf compresses, we investigated the effects of Brassica oleracea derived miR172a on the potential human target gene encoding FAN (Factor Associated with Neutral Sphingomyelinase Activation) protein. In vitro experiments showed a decrease in FAN protein levels in both human and mouse cells transfected with bol-miRNA172a. As the FAN protein mediates inflammatory responses, the potential of miR172a to mitigate the inflammatory process was tested in a mouse model of rheumatoid arthritis. Animal studies showed the decreased oedema of inflamed paws in mouse with rheumatoid arthritis model induced after treatment with miR172a.

Characterization of the MicroRNA Profile of Ginger Exosome-like Nanoparticles and Their Anti-Inflammatory Effects in Intestinal Caco-2 Cells

Plant-derived exosome-like nanoparticles (PELNs) have been shown to enter mammalian cells for disease treatment. Although abundant miRNAs are contained in ginger exosome-like nanoparticles (GELNs), little is known about their type and function. Herein, we extracted GELNs with desirable particle sizes (156 ± 36 nm) and a negative surface charge (-26.6 ± 5 mV). The miRNA profiles in ginger and GELNs were analyzed using high-throughput sequencing, and the results of the sequencing were validated by real-time quantitative polymerase chain reaction (RT-qPCR). There were 27 miRNAs with higher expression levels in the GELNs, and they were mainly involved in the regulation of inflammatory and cancer-related pathways. Furthermore, GELNs could be specifically internalized by intestine cells via caveolin-mediated endocytosis and micropinocytosis, as well as counteract lipopolysaccharide (LPS)-induced inflammation by downregulating NF-κβ, IL-6, IL-8, and TNF-α expression. Importantly, the positive effects were further proved to be possibly related to the miRNAs enriched in the GELNs. Overall, these results indicated that PELNs could target human digestive organs and play a cross-kingdom physiological regulation role through miRNAs.

Understanding the Molecular Mechanisms of Betel miRNAs on Human Health.

Since ancient times, "betel leaf" (Piper betle) has been revered for its religious, cultural, and medicinal properties. Phytochemicals from the Piper betle are effective in a variety of conditions, including cancer. To date, however, no genomic study or evidence has been found to elucidate the regulatory mechanism that underpins its therapeutic properties. This is the first study of its kind to predict Piper betle miRNAs and also the first genomics source representation of Piper betle. According to previous research, miRNAs from the plants we eat can regulate gene expression. In line with this, our in-silico study revealed that Piper betle and human cross-kingdom control occurs. This study demonstrates the prediction and in-silico validation of Piper betle miRNAs from NGS-derived transcript sequences. The cross-kingdom regulation, which can also be understood as inter- species RNA regulation, was studied to identify human mRNA targets controlled by Piper betle miRNAs. Functional annotation and gene-disease association of human targets were performed to understand the role of Piper betle miRNAs in human health and disease. The protein-protein interaction and expression study of targets was further carried out to decipher their role in cancer development. Identified six Piper betle miRNAs belonging to miR156, miR164, miR172, and miR535 families were discovered to target 198 human mRNAs involved in various metabolic and disease processes. Angiogenesis and the cell surface signaling pathway were the most enriched gene ontology correlated with targets, both of which play a critical role in disease mechanisms, especially in the case of carcinoma. In an analysis of gene-disease interactions, 40 genes were found to be related to cancer. According to a protein-protein interaction, the CDK6 gene, which is thought to be a central regulator of cell cycle progression, was found as a hub protein, affecting the roles of CBFB, SAMD9, MDM4, AXIN2, and NOTCH2 oncogenes. Further investigation revealed that pbe-miRNA164a can be used as a regulator to minimise disease severity in Acute Myeloid Leukemia, where CDK6 expression is highest compared to normal cells. The predicted pbe-miRNA164a in this study can be a promising suppressor of CDK6 gene involved in tumour angiogenesis. In vivo validation of the pbe-miRNA164a mimic could pave the way for new opportunities to fight cancer and leverage the potential of Piper betle in the healthcare sector.

A fungal microRNA-like RNA subverts host immunity and facilitates pathogen infection by silencing two host receptor-like kinase genes.

Small RNAs (sRNAs) play important roles in various biological processes by silencing their corresponding target genes in most eukaryotes. However, cross-kingdom regulation mediated by fungal microRNA-like RNAs (milRNAs) in plant-pathogen interactions is still largely unknown. Using molecular, genetic, histological, and biochemical approaches, we found that the apple tree Valsa canker pathogen Valsa mali milRNA Vm-milR1 could suppress the host immunity by silencing two host receptor-like kinase genes, MdRLKT1 and MdRLKT2. Vm-milR1 was highly induced during V. mali infection. Deletion of Vm-milR1 precursor abolished the generation of Vm-milR1 and reduced the virulence of V. mali. Inoculation of Vm-milR1 deletion mutants induced the host defence responses, including reactive oxygen species (ROS) accumulation, callose deposition, and high expression of defence-related genes. Furthermore, Vm-milR1 was confirmed to be able to suppress the expression of MdRLKT1 and MdRLKT2 in a sequence-specific manner. Moreover, overexpression of either MdRLKT1 or MdRLKT2 enhanced apple resistance to V. mali by activating the host defence responses. Furthermore, knockdown of MdRLKT1 or MdRLKT2 compromised the host resistance to V. mali. Our study revealed that V. mali was equipped with Vm-milR1 as an sRNA effector to silence host receptor-like kinase genes, suppress the host defence responses, and facilitate pathogen infection.

Targeting Bone Metastases Signaling Pathway Using Moringa oleifera Seed Nutri-miRs: A Cross Kingdom Approach

Moringa oleifera is a medicinally important plant that has various medical and nutritional uses. Plant miRNAs are a class of non-coding endogenous small RNAs that regulate human-specific mRNA but the mechanistic actions are largely unknown. Here, in this study, we aim to explore the mechanistic action and influence of M. oleifera seed miRNAs on vital human target genes using computer based approaches. The M. oleifera seed miRNAs sequence was taken from published data and identified its human gene targets using a psRNA target analysis server. We identified 94 miRNAs that are able to significantly regulate 47 human target genes, which has enormous biological and functional importance. Out of 47 human targeted genes, 23 genes were found to be associated with PI3K-AKT, RUNX, and MAPK1/MAPK3 signaling pathway which has shown to play key roles in bone metastases during cancer progression. The M. oleifera seed miRNAs hold a strong potential for future research that might uncover the possibility of miRNA-facilitated cross-kingdom regulation and therapeutic targets for bone metastases.

Extracellular Vesicles: Emerging Players in Plant Defense Against Pathogens.

Communication between plants and interacting microorganisms requires functional molecule trafficking, which is essential for host defense and pathogen virulence. Extracellular vesicles (EVs) are single membrane-bound spheres that carry complex cargos, including lipids, proteins, and nucleic acids. They mediate cell-to-cell communication via the transfer of molecules between cells. Plant EVs have been isolated from many plant species and play a prominent role in immune system modulation and plant defense response. Recent studies have shown that plant EVs are emerging players in cross-kingdom regulation and contribute to plant immunity by mediating the trafficking of regulatory small RNA into pathogens, leading to the silencing of pathogen virulence-related genes. This review summarizes the current understanding of plant EV isolation technologies, the role of plant EVs in plant immunity, and the mechanism of plant EV biogenesis, as well as approaches for how these findings can be developed into innovative strategies for crop protection.

Low pH-Based Method to Increase the Yield of Plant-Derived Nanoparticles from Fresh Ginger Rhizomes.

Plant-derived nanoparticles (PDNPs) are naturally occurring exosome-like nanovesicles derived from dietary plants containing key plant bioactives. Ginger-derived PDNPs have a therapeutic effect on alcohol-induced liver injury, inflammatory bowel disease, and colon cancer. PDNPs are conventionally purified by differential ultracentrifugation, a technique not amenable for scale up. We have recently developed a polyethylene glycol (PEG) 6000-based method for cost-effective purification of ginger PDNPs, with comparable efficiency to differential ultracentrifugation (Sci. Rep.2020, 10 (1), 4456.). Herein, we report a 4–5-fold higher ginger PDNP recovery when PEG precipitation was carried out in low pH conditions (pH 4 and 5). Low pH-derived ginger PDNPs were smaller in size without an overt change in zeta potential. The spontaneous intracellular entry and protection against oxidative stress in A431 cells were similar between ginger PDNPs purified under low, neutral, and alkaline pH. Low-pH purified ginger PDNPs had higher levels of total polyphenolic content compared to PDNPs purified under neutral and alkaline pH. Recently, ginger PDNP-derived microRNAs have been shown to exhibit cross-kingdom regulation by targeting human, gut microbiome, and viral transcripts. Using qRT-PCR, we also verified the presence of miRNAs that were predicted to target SARS-CoV-2 in ginger PDNPs purified under low pH. Thus, we have developed a method to purify ginger PDNPs in high yields by using low-pH conditions without affecting the major bioactive contents of PDNPs.

A Timely Review of Cross-Kingdom Regulation of Plant-Derived MicroRNAs.

MicroRNAs (miRNAs) belong to a class of non-coding RNAs that suppress gene expression by complementary oligonucleotide binding to the sites in target messenger RNAs. Numerous studies have demonstrated that miRNAs play crucial role in virtually all cellular processes of both plants and animals, such as cell growth, cell division, differentiation, proliferation and apoptosis. The study of rice MIR168a has demonstrated for the first time that exogenous plant MIR168a influences cholesterol transport in mice by inhibiting low-density lipoprotein receptor adapter protein 1 expression. Inspired by this finding, the cross-kingdom regulation of plant-derived miRNAs has drawn a lot of attention because of its capability to provide novel therapeutic agents in the treatment of miRNA deregulation-related diseases. Notably, unlike mRNA, some plant miRNAs are robust because of their 3′ end modification, high G, C content, and the protection by microvesicles, miRNAs protein cofactors or plant ingredients. The stability of these small molecules guarantees the reliability of plant miRNAs in clinical application. Although the function of endogenous miRNAs has been widely investigated, the cross-kingdom regulation of plant-derived miRNAs is still in its infancy. Herein, this review summarizes the current knowledge regarding the anti-virus, anti-tumor, anti-inflammatory, anti-apoptosis, immune modulation, and intestinal function regulation effects of plant-derived miRNAs in mammals. It is expected that exploring the versatile role of plant-derived miRNAs may lay the foundation for further study and application of these newly recognized, non-toxic, and inexpensive plant active ingredients.

Hepatoprotective plants role in human health: A cross-kingdom review

Liver, being one of the most fundamental and vital organ existing in human body and performing significant role in regulation of enormous number of biological processes including metabolism of biomolecules, secretion, storage, detoxification and excretion of xenobiotics from body. Accomplishment of all these processes leads to acute or chronic hepatic injuries and liver dysfunctions, which sequentially contributes to global health care threat as well as it is a concern for pharmaceutical industry as despite all advancements in medicine there is still a lack of completely assured hepato-protective drugs which stimulate and enhance liver function. However, nature full fills these vacant spaces by providing a number of plant derived hepatoprotective phytochemicals, which are comparatively less toxic and this leads to introduction of an alternative phytotherapeutic approach i.e., the use of poly herbal formulations for treatment of liver diseases. Throughout the world, herbalists claim the use of a number of remedial plants for treatment of hepatic dysfunctions. Nevertheless, recent research also reveals that not only phytochemicals, but also regulatory microRNAs are being transferred from plant to animal kingdom. Thus, this leads to an alternative concept of cross-kingdom gene regulation by non-coding tiny molecules i.e. orally consumed plant derived xeno-MIRs play a chief role in human health regulation. The abilities of microRNAs to regulate cross-kingdom gene regulation have prompted the hopes to explore this novel concept in diagnosis, prognosis and treatment as potential therapeutic and dietary supplements. The present review is aimed to compile the available data of promising hepatoprotective plants and introduce the cross-kingdom gene regulation approach as potential therapy for human health care.

Eating microRNAs: pharmacological opportunities for cross-kingdom regulation and implications in host gene and gut microbiota modulation.

Cross-kingdom communication via non-coding RNAs is a recent discovery. Exogenous microRNAs (exog-miRNAs) mainly enter the host via the diet. Generally considered unstable in the gastrointestinal tract, some exogenous RNAs may resist these conditions, especially if transported in extracellular vesicles. They could then reach the intestines and more probably exert a regulatory effect. We give an overview of recent discoveries concerning dietary miRNAs, possible ways of enhancing their resistance to food processing and gut conditions, their transport in extracellular vesicles (animal- and plant-origin) and possible biological effects on recipient cells after ingestion. We critically focus on what we believe are the most relevant data for future pharmacological development of dietary miRNAs as therapeutic agents. Finally, we discuss the miRNA-mediated cross-kingdom regulation between diet, host and the gut microbiota. We conclude that, despite many obstacles and challenges, extracellular miRNAs are serious candidates to be targeted pharmacologically for development of new therapeutic agents.

Edible plant-derived exosomal microRNAs: Exploiting a cross-kingdom regulatory mechanism for targeting SARS-CoV-2

BackgroundThe current COVID-19 pandemic is caused by SARS-CoV-2 which belongs to coronaviridae family. Despite the global prevalence, there are currently no vaccines or drugs. Dietary plant derived exosome-like vesicles are known as edible nanoparticles (ENPs). ENPs are filled with microRNAs (miRNAs), in bioavailable form. Recently, cross-kingdom regulation of human transcripts by plant miRNAs have been demonstrated. However, ENP derived miRNAs targeting SARS-CoV-2 has not been described. Study designMature ENP-derived miRNA sequences were retrieved from small RNA sequencing datasets available in the literature. In silico target prediction was performed to identify miRNAs that could target SARS-CoV-2. ENPs were isolated from ginger and grapefruit plants and the expression of SARS-CoV-2 targeting miRNAs were confirmed by qRT-PCR. ResultsFrom a total of 260 ENP-derived miRNAs, we identified 22 miRNAs that could potentially target SARS-CoV-2 genome. 11 miRNAs showed absolute target specificity towards SARS-CoV-2 but not SARS-CoV. ENPs from soybean, ginger, hamimelon, grapefruit, tomato and pear possess multiple miRNAs targeting different regions within SARS-CoV-2. Interestingly, osa/cme miR-530b-5p specifically targeted the ribosomal slippage site between ORF1a and ORF1b. We validated the relative expression of six miRNAs (miR-5077, miR-6300, miR-156a, miR-169, miR-5059 and miR-166 m) in ginger and grapefruit ENPs by RT-PCR which showed differential enrichment of specific miRNAs in ginger and grapefruit ENPs. ConclusionSince administration of ENPs leads to their accumulation into lung tissues in vivo, ENP derived miRNAs targeting SARS-CoV-2 genome has the potential to be developed as an alternative therapy.

Cross-Kingdom Regulation by Plant microRNAs Provides Novel Insight into Gene Regulation

microRNAs (miRNAs) are well known as major players in mammalian and plant genetic systems that act by regulating gene expression at the post-transcriptional level. These tiny molecules can regulate target genes (mRNAs) through either cleavage or translational inhibition. Recently, the discovery of plant-derived miRNAs showing cross-kingdom abilities to regulate mammalian gene expression has prompted exciting discussions among researchers. After being acquired orally through the diet, plant miRNAs can survive in the digestive tract, enter the circulatory system, and regulate endogenous mRNAs. Here, we review current knowledge regarding the cross-kingdom mechanisms of plant miRNAs, related controversies, and potential applications of these miRNAs in dietary therapy, which will provide new insights for plant miRNA investigations related to health issues in humans.

Cross-kingdom regulation by dietary plant miRNAs: an evidence-based review with recent updates.

As non-coding RNA molecules, microRNAs (miRNAs) are widely known for their critical role in gene regulation. Recent studies have shown that plant miRNAs obtained through dietary oral administration can survive in the gastrointestinal (GI) tract, enter the circulatory system and regulate endogenous mRNAs. Diet-derived plant miRNAs have 2'-O-methylated modified 3'ends and high cytosine and guanine (GC) content, as well as exosomal packaging, which gives them high stability even in the harsh environment of the digestive system and circulatory system. The latest evidence shows that dietary plant miRNAs can not only be absorbed in the intestine, but also be absorbed and packaged by gastric epithelial cells and then secreted into the circulatory system. Alternatively, these biologically active plant-derived miRNAs may also affect the health of the host by affecting the function of the microbiome, while not need to be taken into the host's circulatory system and transferred to remote tissues. This cross-kingdom regulation of miRNAs gives us hope for exploring their therapeutic potential and as dietary supplements. However, doubts have also been raised about the cross-border regulation of miRNAs, suggesting that technical flaws in the experiments may have led to this hypothesis. In this article, we summarize the visibility of dietary plant miRNAs in the development of human health and recent research data on their use in therapeutics. The regulation of plant miRNAs across kingdoms is a novel concept. Continued efforts in this area will broaden our understanding of the biological role of plant miRNAs and will open the way for the development of new approaches to prevent or treat human diseases.

SKLB CoralBioinfo Database: A High-Quality Multi-Omics Platform for Reef-Building Coral Research

Although reef-building corals play an important role in the global marine ecosystem, there emerges a huge lack of omics data as well as databases from these species, exerting negative effects on exploring their biology. Here we introduce the construction of SKLB CoralBioinfo database series ( http://bmeonline.cn/coralbioinfo ), which integrate our new multi-omics sequencing data from various main reef-building coral species with other existing coral bio-data. Main-database CoralBioinfo storing basic bioinformatics data lay the foundation for down-stream analysis and development, while sub-databases CoralmiR and CoralSym constitute reef-building coral miRNA dataset together to pave the way for cross-kingdom regulation research. Embedded with multiple web services, SKLB CoralBioinfo is expected to fulfil the “data gap” and help the scientific community deepen understanding of coral biology.

Integration of small RNAs, degradome, and transcriptome sequencing provides insights into the differences between Shizhu ginseng and Yuan ginseng

Panax ginseng is one of the most popular herbs which have been used as an important traditional Chinese medicine since ancient times. Yuan ginseng and Shizhu ginseng,which belong to P. ginseng, are widely used as substitutes for wild ginseng in clinical practice. Clinical practice has proved that the clinical efficacy of Shizhu ginseng is better than Yuan ginseng. However, current research cannot completely explain this phenomenon. Considering that small RNA may be one of the pharmacodynamic substances of P. ginseng, it is challenging to investigate differential miRNAs between Shizhu ginseng and Yuan ginseng. In this study, the transcriptome, small RNAome and degradome of P. ginseng were studied by high-throughput sequencing. A total of 63,875 unigenes and 43,950,137 small RNA clean reads were obtained from the roots of P. ginseng. Among 3206 differentially expressed genes, 1190 genes were up-regulated in Yuan ginseng when compared with Shizhu ginseng. 24 known differential miRNAs and 7 novel differential miRNAs were obtained. The 304 targets of 24 differentially expressed miRNA (17 known and 7 novel) families are mainly related to energy metabolism, biotic stress and disease immunity in ginseng itself. Through the association analysis of mRNA and miRNA, our work gives a better understanding of the difference between Yuan ginseng and Shizhu ginseng. Considering the cross-kingdom regulation of plant miRNAs, our results may provide a foundation for understanding the miRNA-dependent clinical efficacy in P. ginseng.

Novel tomato miRNA miR1001 initiates cross-species regulation to suppress the conidiospore germination and infection virulence of Botrytis cinerea in vitro.

Recent evidence has shown that microRNAs are transferred from one species to another through cross-species transmission and exhibit biological activities in the receptor. However, the cross-kingdom regulation of pathogen virulence by plant-derived miRNAs is rarely reported. This study investigated the regulatory role of novel tomato miRNA miR1001 in the growth and development of Botrytis cinerea. Results showed that miR1001 inhibited the virulence of B. cinerea-infected plants, and the inhibitory effect of miR1001/miR1001* was stronger than that of miR1001. Moreover, miR1001 exerted a significant inhibitory effect on the conidiospore germination of B. cinerea. Degradome-seq experiment showed that miR1001 can directly target the Bcin03g02170.1 and Bcin10g01400.1 genes, which respectively encode the ATP-dependent metallopeptidase and cysteine-type endopeptidase, in B. cinerea. The interactions of both targets with miR1001 were further confirmed by using transient co-expression in tobacco. Real-time RT-PCR analysis showed that the expression levels of the two target genes were significantly downregulated in B. cinerea with miR1001 treatment. Our findings provide new evidence into the coevolution of pathogens and host plants, as well as new directions for the use of plant-derived miRNAs to control pathogens.

Salvia miltiorrhiza-Derived Sal-miR-58 Induces Autophagy and Attenuates Inflammation in Vascular Smooth Muscle Cells

Autophagy is associated with the cytoprotection of physiological processes against inflammation and oxidative stress. Salvia miltiorrhiza possesses cardiovascular protective actions and has powerful anti-oxidative and anti-inflammatory effects; however, whether and how Salvia miltiorrhiza-derived microRNAs (miRNAs) protect vascular smooth muscle cells (VSMCs) by inducing autophagy across species are unknown. We first screened and identified Sal-miR-58 from Salvia miltiorrhiza as a natural autophagy inducer. Synthetic Sal-miR-58 suppresses chronic angiotensin II (Ang II) infusion-induced abdominal aortic aneurysm (AAA) formation in mice, as well as induces autophagy in VSMCs and attenuates the inflammatory response elicited by Ang II in vivo and in vitro. Mechanistically, Sal-miR-58 downregulates Krüppel-like factor 3 (KLF3) expression through direct binding to the 3′ UTR of KLF3, which in turn relieves KLF3 repression of E3 ubiquitin ligase neural precursor cell-expressed developmentally downregulated 4-like (NEDD4L) expression, whereas NEDD4L upregulation increases the ubiquitination and degradation of the platelet isoform of phosphofructokinase (PFKP), subsequently leading to a decrease in the activation of Akt/mammalian target of rapamycin (mTOR) signaling and facilitating VSMC autophagy induced by Sal-miR-58 in the context of chronic Ang II stimulation and aneurysm formation. Our results provide the first evidence that plant-derived Sal-miR-58 induces autophagy and attenuates inflammation in VSMCs through cross-species modulation of the KLF3/NEDD4L/PFKP regulatory pathway.