Isolation of nucleoproteins.-Many methods for isolating nucleoproteins involve a stage, either during the extraction or more generally in the precipitation process, which is relatively drastic and may produce an alteration in the chemical and physical properties of the nucleoprotein ; thus the majority of preparations involve precipitation of the extracted material with hydrochloric or acetic a...

Yellow head virus (YHV) is an invertebrate nidovirus that is highly pathogenic for marine shrimp. Nucleotide sequence analysis indicated that the YHV ORF2 gene encodes a basic protein (pI = 9.9) of 146 amino acids with a predicted molecular weight of 16,325.5 Da. The deduced amino acid sequence indicated a predominance of basic (15.1%), acidic (9.6%) and hydrophilic polar (34.3%) residues and a...

Human Rad51 (hRad51), the protein central to DNA pairing and strand exchange during homologous recombination, polymerizes on DNA to form nucleoprotein filaments. By making use of magnetic tweezers to manipulate individual DNA molecules, we measured the nucleation and growth of hRad51 nucleoprotein filaments, and their subsequent disassembly in real time. The dependence of the initial polymeriza...

Spring viraemia of carp virus (SVCV) is an aetiological agent of a serious disease affecting carp farms in Europe and is a member of the Rhabdoviridae family of viruses. The genome of SVCV codes for five proteins: nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G) and RNA-dependent RNA polymerase (L). RNA-mediated interference (RNAi) by small interfering RNAs (siRNAs) i...

The human recombinase hRad51 is a key protein for the maintenance of genome integrity and for cancer development. Polymerization and depolymerization of hRad51 on duplex DNA were studied here using a new generation of magnetic tweezers, measuring DNA twist in real time with a resolution of 5 degrees . Our results combined with earlier structural information suggest that DNA is somewhat less ext...

Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic pathogen causing severe outbreaks in humans and livestock in sub-Saharan Africa and the Arabian Peninsula. Human infections are characterized by fever, sometimes leading to encephalitis, retinitis, hemorrhagic fever, and occasionally death. There are currently no fully licensed vaccines or effective therapies for human use. Gene silenc...

MicroRNA-21 (miR-21) is overexpressed in patients with rheumatoid arthritis (RA). This study was designed to investigate the effect and mechanism of miR-21 on cell proliferation in fibroblast-like synoviocytes (FLS) of RA. FLS were primary-cultured from a rat RA model. RA-FLS and normal FLS were infected with lentivirus (anti-miR-21 or pro-miR-21) for overexpression or downregulation of miR-21,...

Protein-mediated self-assembly is arguably one of the most promising routes for building complex molecular nanostructures. Here, we report a molecular self-assembly technique that allows programmable, site-specific patterning of double-stranded DNA scaffolds, at a single-base resolution, by 3-nm-long RecA-based nucleoprotein filaments. RecA proteins bind to single-stranded DNA to form nucleopro...

The present work was undertaken to study the distribution of yeast nucleoprotein in cell fractions after centrifugal separation, and to define conditions of extraction and purification in order to obtain the nucleoprotein in a relatively undegraded state. Bakers’ yeast (Xaccharomyces cerevisiae) is the classical source of ribonucleic acid (RNA), but relatively little work has been reported on t...