Illness and Diseases

5′-UTR sequence of DHV-1 ZJ strain (GenBank No. EF382778) was aligned with other DHV-1 isolates from GenBank using DNAstar (DNASTAR Inc.) software. Secondary structure elements were predicted in Mfold. Plasmid construction DNA preparations were performed using standard methods as described in manufacturers’ instructions. The reporter plasmids pGEM-CAT/EMC/LUC, containing the EMCV IRES cDNA, and pGEM-CAT/LUC were […]

Some picornaviruses, such as the AEV, contain HCV-like IRES elements organized in two major secondary structure domains, II and III, in which all the structural elements crucial for initiation of translation are located. Mutations within the putative loop of domain IIIe and stem1, 2 inhibited the DHV-1 IRES function. Moreover, the restoration of these structures […]

In order to evaluate the contribution of the remaining component of the eIF4F complex, the RNA helicase eIF4A, two different experimental in vitro approaches were used. Firstly, the effect on DHV-1 translation initiation of two different dominant negative mutants of eIF4A was evaluated. The dominant negative mutant PRRVAA contains a mutation in the conserved Ia […]

DHV-1 IRES activity is modulated by downstream coding sequences To further characterize the presence of accessory regulatory sequences downstream of the 5′-UTR of the viral genome, 4 additional dicistronic reporter plasmids were constructed, containing DHV-1 5′-UTR and 10, 40 or 60 nucleotides of the coding region adjacent to the viral 5′-UTR (DHV-1 UTR+10nt, UTR+40nt, UTR+60nt, […]

The in vitro translation of the reporter proteins was evaluated measuring 35S-methionine incorporation. Cap-dependent translation from the first ORF was determined by the level of CAT expression and internal initiation activity of the different sequences included between the two reporter genes was estimated by the accumulation of fLUC. All the mRNAs expressed CAT efficiently as […]

According to their secondary structure, picornavirus IRES elements can be divided into four groups that display distinct biological properties. The first group (class I) includes the IRES elements from entero- and rhinoviruses (e.g. poliovirus, PV), while the second includes cardio- and aphthoviruses IRES elements (e.g. encephalomyocarditis virus, EMCV). The IRES element from hepatitis A virus […]

Duck hepatitis virus (DHV-1) is a worldwide distributed picornavirus that causes acute and fatal disease in young ducklings. Recently, the complete genome of DHV-1 has been determined and comparative sequence analysis has shown that possesses the typical picornavirus organization but exhibits several unique features. For the first time, we provide evidence that the 626-nucleotide-long 5′-UTR […]