MicroRNAs (miRNAs) are non-coding small RNAs (sRNAs) that regulate gene expression in a wide range of eukaryotes. In this study, we analyzed regulatory sRNAs in Penicillium chrysogenum, the industrial producer of the β-lactam antibiotic penicillin. To identify sRNAs and microRNA-like RNAs (milRNAs) on a global approach, two sRNA sequencing libraries were constructed. One library was created wit...

Malfunction of protein translation causes many severe diseases, and suitable correction strategies may become the basis of effective therapies. One major regulatory element of protein translation is the nuclease Dicer that cuts double-stranded RNA independently of the sequence into pieces of 19-22 base pairs starting the RNA interference pathway and activating miRNAs. Inhibiting Dicer is not de...

MicroRNAs (miRNAs), small 19-25 nucleotide RNAs that influence gene expression through posttranscriptional regulation of mRNA translation and degradation, have recently emerged as important regulators of neural development. Using conditional knock-out of Dicer, an RNase III enzyme required for miRNA maturation, previous studies have demonstrated an essential role for miRNAs in mouse cortical, i...

HIF-1a, one of the most extensively studied oncogenes, is activated by a variety of microenvironmental factors. The resulting biological effects are thought to depend on its transcriptional activity. The RNAse enzyme Dicer is frequently downregulated in human cancers, which has been functionally linked to enhanced metastatic properties; however, current knowledge of the upstream mechanisms regu...

The deep-sequencing of small RNAs has revealed that different numbers and proportions of miRNA variants called isomiRs are formed from single miRNA genes and that this effect is attributable mainly to imprecise cleavage by Drosha and Dicer. Factors that influence the degree of cleavage precision of Drosha and Dicer are under investigation, and their identification may improve our understanding ...

Mammalian Dicer interacts with double-stranded RNA-binding protein TRBP or PACT to mediate RNA interference and micro-RNA processing. TRBP and PACT are structurally related but exert opposite regulatory activities on PKR. It is not understood whether TRBP and PACT are simultaneously required for Dicer. Here we show that TRBP directly interacts with PACT in vitro and in mammalian cells. TRBP and...

Gene regulation by small RNA pathways is ubiquitous among eukaryotes, but little is known about small RNA pathways in the Stramenopile kingdom. Phytophthora, a genus of filamentous oomycetes, contains many devastating plant pathogens, causing multibillion-dollar damage to crops, ornamental plants, and natural environments. The genomes of several oomycetes including Phytophthora species such as ...

Up until 2006 it was believed that most, if not all, small RNAs in RNA silencing were synthesized via members of the Dicer-like RNase III endonuclease family. In animals, small interfering RNAs (siRNAs) are cleaved from long double-stranded RNA by Dicer enzymes, and microRNAs (miRNAs) are released from genome-encoded stem-loop precursors through the sequential action of Droshas and Dicers. In p...

OBJECTIVE Key molecules involved in microRNA (miRNA) biogenesis, such as DROSHA, XPO5, and DICER, have been identified in trophoblast cells, confirming that the miRNA biogenesis pathway is active in human placenta. In addition, miRNAs regulate uterine gene expression associated with inflammatory responses during the peri-implantation period and participate in maternal-fetal immune tolerance. Th...

OBJECTIVES Although numerous recent studies have focused on analyses of microRNA expression profiles in cancer cells, the expression patterns of the enzymes responsible for the generation of miRNAs remains largely unexplored. The purpose of this study was to investigate whether Dicer mRNA expression is altered during progression of ovarian cancer. DESIGN AND METHODS Total RNA was extracted fr...