Identification of Novel Genes Coding for Small Expressed RNAs

Abstract

In Caenorhabditis elegans, lin-4 and let-7 encode 22- and 21-nucleotide (nt) RNAs, respectively, which function as key regulators of developmental timing. Because the appearance of these short RNAs is regulated during development, they are also referred to as small temporal RNAs (stRNAs). We show that many 21- and 22-nt expressed RNAs, termed microRNAs, exist in invertebrates and vertebrates and that some of these novel RNAs, similar to let-7 stRNA, are highly conserved. This suggests that sequence-specific, posttranscriptional regulatory mechanisms mediated by small RNAs are more general than previously appreciated.

MicroRNA-409 suppresses tumour cell invasion and metastasis by directly targeting radixin in gastric cancers

“…8 miRNAs can bind to complementary sequences in the 3 0 -untranslated regions (3 0 -UTR) of their target mRNAs and induce mRNA degradation or translational repression. 9 An increasing number of studies indicate that miRNAs are involved in many important biological processes, including proliferation, apoptosis, differentiation, angiogenesis and immune response, with deregulation leading to aberrant gene expression in various diseases.…”

Genome‐wide identification, expression profiling, and target gene analysis of microRNAs in the Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), vectors of tospoviruses (Bunyaviridae)

“…The first miRNA, Lin‐4 gene, was discovered by Lee, Feinbaum, and Ambros (1993) in Caenorhabditis elegans . Consequently, several miRNAs have been discovered from wide varieties of organisms including insects (Lagos‐Quintana, Rauhut, Lendeckel, & Tuschl, 2001), plants (Bartel, 2004), viruses (Cullen, 2006), and vertebrates (Lim, Glasner, Yekta, Burge, & Bartel, 2003). …”

“…Identification of miRNA includes three principle approaches, forward genetics, bioinformatics prediction (Rebijith et al., 2014; Zhang, Pan, Cannon, Cobb, & Anderson, 2006), and direct cloning and sequencing (Chen et al., 2005; Lagos‐Quintana et al., 2001; Lee & Ambros, 2001). High‐throughput next‐generation sequencing (NGS) emerged as a powerful tool to identify miRNAs from animals and plants (Calla & Geib, 2015; Guillem, Bastian, Maria‐Dolors, & Xavier, 2016; Nandety, Sharif, Kamita, Ramasamy, & Falk, 2015; Song et al., 2011; Wang et al., 2012; Wu et al., 2013).…”

Two-dimensional fluorescence difference gel electrophoresis for comparative proteomics profiling

“…The necessity to evaluate the proteome is based on the knowledge that higher organisms have several means for controlling cellular function and that proteins mediate the greater part of biological events in the cell, even though certain RNAs can act as effector molecules. However, there are several factors that prevent the linear association of RNA and protein levels (transcription to translation) 15,16 , including single genes that can be translated in several protein products, differential responsivity of mRNA and proteins to intra-and extracellular stimuli, post-transcriptional changes in mRNA (alternative splicing, RNA editing), post-translational modifications of proteins that affect functionality and trafficking (phosphorylation, glycosylation, methylation, palmitoylation) 17 and, most recently, the discovery of microRNAs, which regulate the conversion of mRNAs to proteins [18][19][20] . To evaluate comprehensively the cellular alterations in health and disease, it is essential to determine the alternations in proteins in as complete a manner as possible 21 .…”