Nucleoprotein

[2][3] Important techniques for determining the structures of nucleoproteins include X-ray diffraction, nuclear magnetic resonance and cryo-electron microscopy.

Structurally characterised viral nucleoproteins include influenza,[6] rabies,[7] Ebola, Bunyamwera,[8] Schmallenberg,[8] Hazara,[9] Crimean-Congo hemorrhagic fever,[10] and Lassa.

[12] The prototypical examples are nucleosomes, complexes in which genomic DNA is wrapped around clusters of eight histone proteins in eukaryotic cell nuclei to form chromatin.

The proteins combined with DNA are histones and protamines; the resulting nucleoproteins are located in chromosomes.

[2][13] In eukaryotic cells, DNA is associated with about an equal mass of histone proteins in a highly condensed nucleoprotein complex called chromatin.

A central intermediate step in this process is the interaction of multiple copies of a recombinase protein with single-stranded DNA to form a DNP filament.

Others are ribonucleoprotein or deoxyribonucleoprotein complexes containing a number of different proteins, and exceptionally more nucleic acid molecules.

Lysine residues in the helical portion of RNA-binding proteins help to stabilize interactions with nucleic acids.

Anti-RNP antibodies are autoantibodies associated with mixed connective tissue disease and are also detected in nearly 40% of Lupus erythematosus patients.

Two types of anti-RNP antibodies are closely related to Sjögren's syndrome: SS-A (Ro) and SS-B (La).

A nucleosome is a combination of DNA + histone proteins .
Cross-sectional drawing of the Ebola virus particle, with structures of the major proteins shown and labelled on the right
Cell nucleus with DNA stained blue, and nucleolin protein in red. The nucleolin protein binds some mRNAs (e.g. mRNA for Interleukin-6 ). This protects those mRNAs from degradation by Kaposi's sarcoma-associated herpesvirus when infected. This RNA-nucleolin complex is then safely transported to the cytosol for translation by ribosomes to produce the Interleukin-6 protein, which is involved in antiviral immune response . [ 19 ]
Cell infected with influenza A virus. Viral ribonucleoprotein particle proteins, stained white, hijack active transport via the endosomes to move more rapidly within the cell than by simple diffusion . [ 26 ]