microRNAs function as effective molecules in regulation of many biological functions of organisms; in most case they regulate gene expression moderately. Emerging evidence suggests that microRNAs play a key role in the regulation of immunological functions including innate and adaptive immune responses. The research on microRNAs would be helpful in elucidation of the mechanisms of human immune system and in development of potential therapies based on microRNAs.
Gene Expression Regulation ; Humans ; Immune System ; physiology ; MicroRNAs ; genetics ; physiology

MicroRNAs (miRNAs) are a class of highly conserved small noncoding RNAs which can regulate gene expression by post-transcriptional degradation or translational repression. miRNAs are involved in the regulation of cell apoptosis, proliferation, differentiation and other physiological processes, and are closely related with development of cancer. More recently, it has been proposed that the presence of genetic variations in microRNA genes, their biogenesis pathway and target binding sites can affect the miRNA processing machinery and targeting, therefore have a significant genetic effect. Since polymorphisms in a miRNA regulatory pathway can result in the loss or gain of a miRNA function and can affect the expression of hundreds of genes, more and more evidence suggested a strong association of miRNA polymorphisms with disease progression, diagnosis and prognosis. Whether in the pathogenesis research of complex diseases or finding biomarkers for diagnosis and prognosis, polymorphisms in the miRNA regulatory pathway have an extremely important value for research.
Animals ; Gene Expression Regulation ; Genetic Variation ; Humans ; MicroRNAs ; genetics ; physiology

Interleukin-8 (IL-8), which is a member of C-X-C chemokine subfamily, is an important activator and chemoattractant for neutrophils and has been implicated in a variety of inflammatory diseases. Numerous reports show that various cells express IL-8 mRNA and produce IL-8 protein rapidly, including monocytes, T lymphocytes, neutrophils, fibroblasts, endothelial cells and epithelial cells. The human IL-8 gene has a length of 5191 bp and contains four exons separated by three introns. It maps to human chromosome 4q12-q21. The mRNA consists of a 101 bases 5' untranslated region, an open reading frame of 297 bases, and a long 3' untranslated region of 1.2 kb. The 5' flanking region of the IL-8 gene contains potential binding sites for several nuclear factors including activated protein-1 (AP-1), activated protein-2 (AP-2), nuclear factor-gene binding (NF-kappa B), nuclear factor-interleukin-6 (NF-IL-6, also calls CAAT/enhancer-binding proteins, C/EBP), IFN regulatory factor-1 (IRF-1), hepatocyte nuclear factor-1 (HNF-1), and so on. IL-8 gene expression is regulated initially at the level of gene transcription. The rapid induction of IL-8 gene expression is likely mediated by latent transcription factors that bind the IL-8 promoter. AP-1 and NF-IL-6 physically interact with NF-kappa B, and functional cooperativity among these factors appears to be critical for optimal IL-8 promoter activity in different cell types. The IL-8 receptor (IL-8R) is a dimeric glycoprotein consisting of a 59 KDa and a 67 KDa subunit. It has been given the name CDw128. It is expressed in many different cell types including those not responding to IL-8. The receptor density is approximately 20,000/cell in neutrophils, 1,040/cell in monocytes, and 300/cell in T-lymphocytes. The IL-8R is a member of the family of G-protein-coupled receptors. There are at least two different IL-8 receptor types (CXCR1 and CXCR2). The activities of IL-8 are not species-specific. IL-8 affects the adhesion of neutrophils to the endothelium and induces the transendothelial migration of neutrophils. IL-8 also exhibits in vitro chemotactic activities against of T-lymphocytes and basophils. IL-8 gene expression can be regulated by fluid shear stress, which may play an important role in the genesis and development of both inflammation and arterosclerosis.
Gene Expression Regulation ; Interleukin-8 ; chemistry ; genetics ; physiology ; Receptors, Interleukin

Cell migration or movement is a highly dynamic cellular process, requiring precise regulation that is essential for a variety of biological processes. microRNAs (miRNAs) are a class of tiny non-coding RNA molecules that function as critical post-transcriptional regulators of gene expression. Emerging evidence demonstrates that miRNAs play important roles in cell migration and directly contribute to extracellular matrix (ECM) remodeling, cell adhesion, and cell signalling that controls cell migration by targeting a large number of protein-coding genes. Accordingly, the dysregulation of these miRNAs has been linked to several migration-related diseases. In this review, we summarize and highlight the recent advances concerning the roles and validated targets of miRNAs in the control of cell movement.
Animals ; Cell Movement ; genetics ; Gene Expression ; Gene Expression Regulation ; Humans ; MicroRNAs ; genetics ; metabolism ; physiology ; RNA ; genetics ; RNA, Untranslated ; genetics

To identify spatiotemporal expression patterns of vernalization genes in common wheat, we analyzed expression characteristics of several vernalization genes (VRN1, VRN2 and VRN3) in the wheat cultivars 'Chinese spring' and 'Luohan 2' by RT-PCR. The VRN1 gene was expressed at different levels in the leaves and roots at the 3-leaf stage, stems, flag leaves at the grain-filling stage, anthers, ovules, and developing seeds in 'Chinese spring'. Expression of VRN1 increased before flowering date, then decreased after flowering time. Expression of VRN1 was not detected in dry seeds or seeds germination. Expression patterns of VRN1 in 'Luohan 2' were similar to those in 'Chinese spring', except that it was not expressed in roots or in the leaves at the 3-leaf stage in 'Luohan 2'. Expression of VRN2 was only detected in the leaves at the 3-leaf stage and in the embryo buds during seeds germination. The Spatiotemporal expression of VRN3 was similar to that of VRN1, except that VRN3 was not expressed in roots. These results improved our understanding of the molecular regulation of vernalization genes in common wheat.
Flowers ; genetics ; physiology ; Gene Expression Regulation, Plant ; genetics ; Genes, Plant ; genetics ; Triticum ; genetics

OBJECTIVEThis article aims to review recent studies on the biological characteristics of long non-coding RNAs (lncRNAs), transcription regulation by lncRNAs, and the results of recent studies on the mechanism of action of lncRNAs in tumor development.

DATA SOURCESThe data cited in this review were mainly obtained from the articles listed in PubMed and HighWire that were published from January 2002 to June 2010. The search terms were "long non-coding RNA", "gene regulation", and "tumor".

STUDY SELECTIONThe mechanism of lncRNAs in gene expression regulation, and tumors concerned with lncRNAs and the role of lncRNAs in oncogenesis.

RESULTSlncRNAs play an important role in transcription regulation by controlling chromatin remodeling, transcriptional control, and post-transcriptional controlling. lncRNAs are involved in many kinds of tumors and play key roles as both suppressing and promoting factors.

CONCLUSIONlncRNAs could perfectly regulate the balance of gene expression system and play important roles in oncogenic cellular transformation.

Animals ; Cell Transformation, Neoplastic ; genetics ; Gene Expression Regulation ; genetics ; physiology ; Humans ; Neoplasms ; genetics ; RNA, Untranslated ; genetics

Brassinosteroid (BR) and gibberellin (GA) are two groups of plant growth regulators essential for normal plant growth and development. To gain insight into the molecular mechanism by which BR and GA regulate the growth and development of plants, especially the monocot plant rice, it is necessary to identify and analyze more genes and proteins that are regulated by them. With the availability of draft sequences of two major types, japonica and indica rice, it has become possible to analyze expression changes of genes and proteins at genome scale. In this review, we summarize rice functional genomic research by using microarray and proteomic approaches and our recent research results focusing on the comparison of cDNA microarray and proteomic analyses of BR- and GA-regulated gene and protein expression in rice. We believe our findings have important implications for understanding the mechanism by which BR and GA regulate the growth and development of rice.
Gene Expression Profiling ; Gene Expression Regulation, Plant ; physiology ; Gibberellins ; metabolism ; Oligonucleotide Array Sequence Analysis ; Oryza ; genetics ; physiology ; Proteomics

The microRNAs (miRNAs) are an evolutionarily conserved class of 22 nucleotide (19 - 25 nt) non-coding RNAs. The miRNAs are partially complementary to 3' untranslated region of target mRNA, resulting in the repression of gene expression at post-transcriptional level. The miRNAs have been associated with diverse biological processes. This review summarizes recent progress of research on the characteristics and function of miRNAs, and the role of miRNAs in hematological malignancy development.
Gene Expression Regulation, Neoplastic ; genetics ; Hematologic Neoplasms ; genetics ; metabolism ; Humans ; MicroRNAs ; genetics ; physiology

Salinity affects more than 6% of the world's total land area, causing massive losses in crop yield. Salinity inhibits plant growth and development through osmotic and ionic stresses; however, some plants exhibit adaptations through osmotic regulation, exclusion, and translocation of accumulated Na+ or Cl-. Currently, there are no practical, economically viable methods for managing salinity, so the best practice is to grow crops with improved tolerance. Germination is the stage in a plant's life cycle most adversely affected by salinity. Barley, the fourth most important cereal crop in the world, has outstanding salinity tolerance, relative to other cereal crops. Here, we review the genetics of salinity tolerance in barley during germination by summarizing reported quantitative trait loci (QTLs) and functional genes. The homologs of candidate genes for salinity tolerance in Arabidopsis, soybean, maize, wheat, and rice have been blasted and mapped on the barley reference genome. The genetic diversity of three reported functional gene families for salt tolerance during barley germination, namely dehydration-responsive element-binding (DREB) protein, somatic embryogenesis receptor-like kinase and aquaporin genes, is discussed. While all three gene families show great diversity in most plant species, the DREB gene family is more diverse in barley than in wheat and rice. Further to this review, a convenient method for screening for salinity tolerance at germination is needed, and the mechanisms of action of the genes involved in salt tolerance need to be identified, validated, and transferred to commercial cultivars for field production in saline soil.
Gene Expression Regulation, Plant ; Genetic Variation ; Germination/physiology* ; Hordeum/physiology* ; Salt Tolerance/genetics*

OBJECTIVETo purify a low-temperature hydroxylamine oxidase (HAO) from a heterotrophic nitrifying bacterium Acinetobacter sp. Y16 and investigate the enzyme property.

METHODSA HAO was purified by an anion-exchange and gel-filtration chromatography from strain Y16. The purity and molecular mass were determined by RP-HPLC and SDS-PAGE. The HAO activity was detected by monitoring the reduction of potassium ferricyanide using hydroxylamine as substrate and ferricyanide as electron acceptor. The partial amino acid sequence was determined by mass spectrometry.

RESULTSThe low-temperature HAO with a molecular mass of 61 kDa was purified from strain Y16 by an anion-exchange and gel-filtration chromatography. The enzyme exhibited an ability to oxidize hydroxylamine in wide temperature range (4-40 °C) in vitro using hydroxylamine as substrate and ferricyanide as electron acceptor. It was stable in the temperature range of 4 to 15 °C and pH range of 6.0 to 8.5 with less than 30% change in its activity. The optimal temperature and pH were 15 °C and 7.5, respectively. Three peptides were determined by mass spectrometry which were shown to be not identical to other reported HAOs.

CONCLUSIONThis is the first study to purify a low-temperature HAO from a heterotrophic nitrifier Acinetobacter sp. It differs from other reported HAOs in molecular mass and enzyme properties. The findings of the present study have suggested that the strain Y16 passes through a hydroxylamine-oxidizing process catalyzed by a low-temperature HAO for ammonium removal.

Acinetobacter ; enzymology ; genetics ; metabolism ; Amino Acid Sequence ; Cold Temperature ; Gene Expression Regulation, Bacterial ; physiology ; Gene Expression Regulation, Enzymologic ; physiology ; Hydrogen-Ion Concentration ; Oxidoreductases ; genetics ; metabolism ; Substrate Specificity