Enterococci with elevated MICs of linezolid and tedizolid should be tested not only for 23S rRNA mutations and the gene cfr, but also for the novel resistance gene optrA.

This report describes the important issues considered by the CAP committee during the development of the new checklist requirements, which address documentation, validation, quality assurance, confirmatory testing, exception logs, monitoring of upgrades, variant interpretation and reporting, incidental findings, data storage, version traceability, and data transfer confidentiality.

Porcine reproductive and respiratory syndrome (PRRS) caused by the PRRS virus (PRRSV) is an important swine disease worldwide. PRRSV has a limited tropism for certain cells, which may at least in part be attributed to the expression of the necessary cellular molecules serving as the virus receptors or factors on host cells for virus binding or entry. However, these molecules conferring PRRSV infection have not been fully characterized. Here we show the identification of non-muscle myosin heavy chain 9 (MYH9) as an essential factor for PRRSV infection using the anti-idiotypic antibody specific to the PRRSV glycoprotein GP5. MYH9 physically interacts with the PRRSV GP5 protein via its C-terminal domain and confers susceptibility of cells to PRRSV infection. These findings indicate that MYH9 is an essential factor for PRRSV infection and provide new insights into PRRSV-host interactions and viral entry, potentially facilitating development of control strategies for this important swine disease.

No abstract

Maternally expressed 3 (MEG3) is a long non-coding RNA that can activate p53 and inhibit tumorigenesis and progression of various types of cancers. However, the role of MEG3 in epithelial ovarian cancer (EOC) is still unknown. The aim of the present study was to confirm whether MEG3 is downregulated in human EOC, determine its possible mechanism of action and elucidate the role of MEG3 in EOC. Differences in the expression of MEG3 and in the methylation status of the MEG3 promoter between EOC and normal ovary were analyzed using RT-PCR and methylation-specific PCR (MSP), respectively. MTT and EdU assays and flow cytometric analysis were used to assess the growth of ovarian cancer cells after overexpression of MEG3. The target genes regulated by MEG3 were detected with the Dual Luciferase Reporter system. The expression levels of target genes were confirmed using RT-PCR and western blotting. In contrast to normal ovarian tissues, the expression of MEG3 was absent or decreased in most EOC tissues as well as in human EOC cell lines, and the promoter of the MEG3 gene was highly methylated in both cancer tissues and cell lines. Treatment with 5-aza-2-deoxycytidine reversed the promoter hypermethylation and increased MEG3 expression. In addition, ectopic expression of MEG3 suppressed the proliferation and growth of OVCAR3 cells and promoted apoptosis. Finally, MEG3 activated p53 in OVCAR3 cells. In conclusion, our data suggest that MEG3 is epigenetically silenced in EOC due to promoter hypermethylation, which may contribute to the development of EOC.

Here we report the rescue of a recombinant porcine reproductive and respiratory syndrome virus (PRRSV) carrying an enhanced green fluorescent protein (EGFP) reporter gene as a separate transcription unit. A copy of the transcription regulatory sequence for ORF6 (TRS6) was inserted between the N protein and 3′-UTR to drive the transcription of the EGFP gene and yield a general purpose expression vector. Successful recovery of PRRSV was obtained using an RNA polymerase II promoter to drive transcription of the full-length virus genome, which was assembled in a bacterial artificial chromosome (BAC). The recombinant virus showed growth replication characteristics similar to those of the wild-type virus in the infected cells. In addition, the recombinant virus stably expressed EGFP for at least 10 passages. EGFP expression was detected at approximately 10 h post infection by live-cell imaging to follow the virus spread in real time and the infection of neighbouring cells occurred predominantly through cell-to-cell-contact. Finally, the recombinant virus generated was found to be an excellent tool for neutralising antibodies and antiviral compound screening. The newly established reverse genetics system for PRRSV could be a useful tool not only to monitor virus spread and screen for neutralising antibodies and antiviral compounds, but also for fundamental research on the biology of the virus.

No abstract

The urbs1 gene encodes a transcriptional regulator of siderophore biosynthesis in Ustilago maydis. Biological and DNA-binding activities of the two putative zincfinger motifs of Urbs1 were studied by analyzing mutants containing altered finger domains. The mutated urbs1 alleles from three previously described N-methyl-N-nitro-Nnitrosoguanidine (NTG) mutants were mapped and cloned by a gap-repair procedure. Sequence analyses revealed single amino acid substitutions in two of the NTG mutants. Both mutations (G-507 to D in urbs1-1 and P-491 to L in urbs1-3), which are located in the Urbs1 C-terminal finger domain, reduced DNA-binding activity by 10-fold and were sufficient to confer a urbs1-minus phenotype. The third NTG urbs1 mutant (urbs1-2) also contained a mutation in one of the conserved amino acids (P-518 to S) in the C-terminal finger domain, but this mutation alone was not sufficient to confer a urbs1-minus phenotype. A second frame shift mutation was identified in urbs1-2 and is necessary for the urbs1-minus phenotype. In an analysis of the function of the N-terminal finger of Urbs1, the conserved amino acid Arg-350 was mutated to leucine. A Urbs1 protein with this mutation complemented a urbs1 null mutant strain. By contrast, a similar mutation in the Cterminal domain abolished the ability of Urbs1 to regulate siderophore biosynthesis and greatly reduced its ability to bind target DNA.