Herpesviruse are enveloping viruses that are prevalent in the human population and are responsible for diverse pathologies; including cold sores; birth defects and cancers; research scientists revealing DNA packaging mechanism of HSV 1, the virus that causes cold sores.
But the intricate machinery responsible for compressing DNA into the small interior shell, or capsid; of herpes simplex virus type 1, or HSV-1; the virus responsible for causing cold sores; The advance could help contribute to the continuing development of improving antiviral therapies; medicines using to treat not just cold sores; but also cancers and birth defects caused by other viruses in the herpesvirus family that frequently target the viral DNA packaging process.
DNA packaging mechanism
The development and use of two techniques for image processing symmetry relaxation and sequential localizing classification that enabling the researchers to produce highly refined 3D images of HSV-1 viral particles; or virions, seeing by cryo electron microscopy. These methods allowing the scientists to see the unique structures in HSV-1.
But traditional 3D reconstruction techniques leverage this symmetry to visualize the virus; but the downside cannot see that deviate from this symmetry. To our amazement, our specialized methods enabled us to see the unique structures of the HS1 virion and much of the viral DNA genome; The DNA packaging process in herpesviruses is fascinating because it’s driven by a nanoscale motor that pumps the viral capsid full of DNA under incredible pressure; up to internal pressures of tens of atmospheres.
But in a standard atmosphere is the amount of air pressure exerted by the Earth’s atmosphere at sea level; or about 14.7 pounds per square inch; The high pressure inside the virion is what makes it possible for the virus to eject its DNA into the cells of the body during viral infection.
But the specialized methods used in this study produced the highest resolution 3-D reconstruction to date of the top of the HSV-1 virus called the portal vertex region which is where viral DNA enters the capsid; managing to map many parts of this area to the level of individual atoms; giving them a detailed look at molecular interactions that have long been areas of great interest to virologists.