In the long-term interaction between pathogens and host, the pathogens regulate the expression of related viru-lence genes to fit the host environment in response to the changes in the host microenvironment. Gene expression was believed to be controlled mainly at the level of transcription initiation by repressors or activators. Recent studies have revealed that small noncoding RNAs (sRNAs) are key regulators in bacterial pathogenesis. sRNA in bacteria is a noncoding RNA with length ranging from 50 to 500 nucleotides. Pathogens can sense the changes in the host environment and consequently regulate the expression of virulence genes by sRNAs. This condition promotes the ability of pathogens to survive within the host, which is beneficial to the invasion and pathogenicity of pathogens. In contrast to transcriptional factors, sRNA-mediated gene regu-lation makes rapid and sensitive responses to environmental cues. Many sRNAs involved in bacterial virulence and pathogenesis have been identified. These sRNAs are key components of coordinated regulation networks, playing important roles in regulating the expression of virulence genes at post-transcriptional level. This review aims to provide an overview on the molecular mechanisms and roles of sRNAs in the regulation of bacterial virulence.
Bacteria ; pathogenicity ; RNA, Bacterial ; RNA, Small Untranslated ; Virulence

In the last several years, we have made slow but steady progress in understanding molecular biology of lung cancer. This review is focused on advances in understanding the biology of lung cancer that have led to proof of concept studies on new therapeutic approaches. The three selected topics include genetics, epigenetics and non-coding RNA. This new information represents progress in the integration of molecular mechanisms that to identify more effective ways to target lung cancer.
Biology ; Epigenomics ; Lung ; Lung Neoplasms ; Molecular Biology ; RNA, Untranslated

OBJECTIVETo explore and identify the non-coding RNAs related to tumors.

METHODSWe used RT-PCR and Northern blot to analyze non-coding RNAs in tumor tissues and cell lines.

RESULTSTwo predicted non-coding RNAs were confirmed to be expressed in cancer tissues and cell lines by RT-PCR and DNA sequencing. We detected the expression of two non-coding RNA transcripts by Northern blot. The length of NC28 was about 1800 nt, and that of NC119 was about 1200nt.

CONCLUSIONSNC28 and NC119 have a tumor-associated expression pattern. The non-coding RNAs may play a role in the development of tumors.

MicroRNAs (miRs) are endogenous approximately22-nt non-coding RNAs that participate in the regulation of gene expression at post-transcriptional level. MiR-1 is one of the muscle-specific miRs, aberrant expression of miR-1 plays important roles in many physiological and pathological processes. In this review, we focus on the recent studies about miR-1 in cardiac diseases and cancers. The findings indicate that miR-1 may be a novel, important biomarker, and a potential therapeutic target in cardiac diseases and cancers.
Gene Expression Regulation ; Heart Diseases* ; MicroRNAs ; Pathologic Processes ; RNA, Untranslated

tRNA-derived RNA fragments (tRFs) are an emerging class of non-coding RNAs (ncRNAs). A growing number of reports have shown that tRFs are not random degradation products but are functional ncRNAs made of specific tRNA cleavage. They play regulatory roles in several biological contexts such as cancer, innate immunity, stress responses, and neurological disorders. In this review, we summarize the biogenesis and functions of tRFs.
Organelle Biogenesis* ; Humans* ; Immunity, Innate ; Nervous System Diseases ; Neurodegenerative Diseases ; RNA* ; RNA, Transfer ; RNA, Untranslated

BACKGROUND: MicroRNAs (miRNAs)are a class of noncoding RNAs found in various organisms such as plants and mammals. However, most of the mRNAs regulated by miRNAs are unknown. Furthermore, miRNA targets in genomes cannot be identified by standard sequence comparison since their complementarity to the target sequence is imperfect in general. In thi s paper, we propose a kernel-based method for the efficient prediction of miRNA targets. To help in distinguishing the false positives from potentially valid targets, we elucidate the features common in experimentally confirmed targets. RESULTS: The performance of our prediction method was evaluated by five-fold cross-validation. Our method showed 0.64 and 0.98 in sensitivity and in specificity, respectively. Also, the proposed method reduced the number of false positives by half compared with TargetScan. We investigated the effect of feature sets on the classification of miRNA targets. Finally, we predicted miRNA targets for several miRNAs in the Caenorhabditis elegans (C.elegans )3'untranslated region (3'UTR) database. CONCLUSIONS: The targets predicted by the suggested method will help in validating more miRNA targets and ultimately in revealing the role of small RNAs in the regulation of genomes. Our algorithm for miRNA target site detection will be able to be improved by additional experimental-knowledge. Also, the increase of the number of confirmed targets is expected to reveal general structural features that can be used to improve their detection.
Caenorhabditis elegans* ; Caenorhabditis* ; Classification ; Genome ; Mammals ; MicroRNAs* ; RNA ; RNA, Messenger ; RNA, Untranslated ; Sensitivity and Specificity

OBJECTIVE: To summarize the regulatory effect of non-coding RNA (ncRNA) on type H vessels angiogenesis of bone. METHODS: Recent domestic and foreign related literature about the regulation of ncRNA in type H vessels angiogenesis was widely reviewed and summarized. RESULTS: Type H vessels is a special subtype of bone vessels with the ability to couple bone formation. At present, the research on ncRNA regulating type H vessels angiogenesis in bone diseases mainly focuses on microRNA, long ncRNA, and small interfering RNA, which can affect the expressions of hypoxia inducible factor 1α, platelet derived growth factor BB, slit guidance ligand 3, and other factors through their own unique ways of action, thus regulating type H vessels angiogenesis and participating in the occurrence and development of bone diseases. CONCLUSION At present, the mechanism of ncRNA regulating bone type H vessels angiogenesis has been preliminarily explored. With the deepening of research, ncRNA is expected to be a new target for the diagnosis and treatment of vascular related bone diseases.
Humans ; RNA, Untranslated/genetics* ; RNA, Long Noncoding ; Bone Diseases/genetics* ; MicroRNAs/genetics* ; RNA, Small Interfering

Metastases account for the overwhelming majority of cancer-associated deaths. The dissemination of cancer cells from the primary tumor to distant organs involves a complex process known as the invasion-metastasis cascade. The underlying biological mechanisms of metastasis, however, remain largely elusive. Recently, the discovery and characterization of non-coding RNAs (ncRNAs) have revealed the diversity of their regulatory roles, especially as key contributors throughout the metastatic cascade. Here, we review recent progress in how three major types of ncRNAs (microRNAs, long non-coding RNAs, and circular RNAs) are involved in the multistep procedure of metastasis. We further examine interactions among the three ncRNAs as well as current progress in their regulatory mechanisms. We also propose the prevention of metastasis in the early stages of cancer progression and discuss current translational studies using ncRNAs as targets for metastasis diagnosis and treatments. These studies provide insights into developing more effective strategies to target metastatic relapse.
Gene Expression Regulation, Neoplastic/genetics* ; RNA, Untranslated/genetics* ; MicroRNAs ; RNA, Long Noncoding ; RNA, Circular/genetics*

nc886 (=vtRNA2-1, pre-miR-886, or CBL3) is a newly identified non-coding RNA (ncRNA) that represses the activity of protein kinase R (PKR). nc886 is transcribed by RNA polymerase III (Pol III) and is intriguingly the first case of a Pol III gene whose expression is silenced by CpG DNA hypermethylation in several types of cancer. PKR is a sensor protein that recognizes evading viruses and induces apoptosis to eliminate infected cells. Like viral infection, nc886 silencing activates PKR and induces apoptosis. Thus, the significance of the nc886:PKR pathway in cancer is to sense and eliminate pre-malignant cells, which is analogous to PKR's role in cellular innate immunity. Beyond this tumor sensing role, nc886 plays a putative tumor suppressor role as supported by experimental evidence. Collectively, nc886 provides a novel example how epigenetic silencing of a ncRNA contributes to tumorigenesis by controlling the activity of its protein ligand.
Apoptosis ; Carcinogenesis ; DNA ; Epigenomics ; Immunity, Innate ; Protein Kinases ; RNA Polymerase III ; RNA, Untranslated*

Long noncoding RNA (lncRNA) is once thought to be the genome transcriptional "noise". However, it has received considerable attention in the past few years and is emerging as potentially important player in biological regulation. Recent studies have revealed that increasing number of lncRNA plays pivotal roles in regulating the gene expression which involves in the development of the human disease. Functions of lncRNA include 3 types of interaction: RNA-RNA, RNA-DNA, and RNA-protein, which may participate in gene expression regulation through epigenetic modifications, transcriptional regulation, post-transcriptional regulation, acting as biological media. Due to the prevalence of obesity and related diseases, some attempts have been done to explore the pathogenesis of obesity from the field of noncoding RNA. Several lncRNAs have been identified to be involved in the regulation of the adipogenesis (white adipose tissue and brown adipose tissue) and energy metabolism. In this review, we summarized recent advances of lncRNAs to provide a new sight for the mechanism of obesity.
Adipogenesis ; genetics ; Epigenesis, Genetic ; Gene Expression Regulation ; Humans ; RNA, Long Noncoding ; physiology ; RNA, Untranslated