The selective degradation of mRNAs by the nonsense-mediated decay pathway is a quality control process with important consequences for human disease. From initial studies using RNA hairpin-tagged mRNAs for purification of messenger ribonucleoproteins assembled on transcripts with HIV-1 3' untranslated region (3'UTR) sequences, we uncover a two-step mechanism for Upf1-dependent degradation of mR...

MicroRNAs (miRNAs) typically downregulate protein expression from target mRNAs through limited base-pairing interactions between the 5' 'seed' region of the miRNA and the mRNA 3' untranslated region (3'UTR). In contrast to this established mode of action, the liver-specific human miR-122 binds at two sites within the hepatitis C viral (HCV) 5'UTR, leading to increased production of infectious v...

Yeast-based in vivo cloning is useful for cloning DNA fragments into plasmid vectors and is based on the ability of yeast to recombine the DNA fragments by homologous recombination. Although this method is efficient, it produces some by-products. We have developed an "ultra-low background DNA cloning system" on the basis of yeast-based in vivo cloning, by almost completely eliminating the gener...

Translationally competent mRNAs form a closed loop via interaction of initiation factors with the 5' cap and poly(A) tail. However, many viral mRNAs lack a cap and/or a poly(A) tail. We show that an uncapped, nonpolyadenylated plant viral mRNA forms a closed loop by direct base-pairing (kissing) of a stem loop in the 3' untranslated region (UTR) with a stem loop in the 5' UTR. This allows a seq...

the aim of this study was to present a model to identify and interpret sport places per capita according to distribution of thiessen networks in geographical information system (gis) space. to execute the model, three regions (5, 6 & 13) of isfahan city were considered and indoor pools were also considered as the sport place sample. dwg-format region maps and their blocks, spatial data and accu...

Cytoplasmic mRNA localization is one method by which protein production is restricted to a particular intracellular site. We report here a novel mechanism for localization of transcripts encoding distinct protein isoforms to different destinations. Alternative processing of transcripts produced in the Drosophila ovary by the hu-li tai shao (hts) locus introduces distinct 3' untranslated regions...

MiRNAs are small (~22nt long) non-coding RNA sequences; binds to the complementarity target sites in 3' Untranslated Region (UTR) of mRNA sequences but not restricted to other mRNA regions viz., 5' UTR and Coding sequences (CDS). Complementarity binding of miRNA to mRNA target sites either results in complete degradation of the mRNA itself or it may regulate the mRNA as an oncogene or as a tumo...

The sequence of the M gene of the Hu2 strain of measles virus has been determined. In the coding region of the gene, six nucleotide replacements had occurred with respect to the sequence of the M gene of the Edmonston strain. Two of these were silent and only four led to amino acid replacements in the protein sequence even though in SDS-PAGE the mobility of the protein would indicate an Mr incr...