Viruses can turn their DNA from a solid to a liquid to infect your cells

By -

New research has found that viruses have a
remarkable biological ability - they can transform
their DNA from a glassy solid into a fluid-like
state to help them infect cells.
Although viruses infect our cells with their DNA
all the time, it’s a process that scientists have
so far struggled to understand - viral DNA is so
tightly packed inside its protein shell that,
technically, it can barely move.
But despite the lack of wiggle room, viruses
somehow manage to inject their DNA into host
cells at high speed all the time. Now scientists
from the US may have found the answer.
Two new studies, both led by Alex Evilevitch
from Carnegie Mellon University and published
last week in the Proceedings of the National
Academy of Sciences and Nature Chemical
Biology, show that, when the conditions are
right, viruses are capable of covering their frozen
and highly pressurised DNA into a liquid that can
invade host cells.
The breakthrough could help scientists to create
new antiviral drugs.
"The exciting part of this is that the physical
properties of packaged DNA play a very
important role in the spread of a viral infection,
and those properties are universal," said
Evilevitch in a press release. "This could lead to
a therapy that isn't linked to the virus' gene
sequence or protein structure, which would make
developing resistance to the therapy highly
unlikely."
Evilevitch and his team looked at the process in
two unrelated viruses, Herpes Simplex, which
infects humans, and bacteriophage lambda,
which infects bacteria. They discovered that in
both viruses, a phase transition occurs at 37
degrees Celsius that allows the DNA to change
from a rigid crystalline structure into a fluid-like
structure.
It’s not a coincidence that this is also the
average human body temperature.
The team used powerful microscopes and x-ray
scattering to help them better understand what
was going on with the viral DNA. They also
discovered that the herpes virus was more likely
to turn its DNA to liquid in conditions similar to
those of neuronal and epithelial cells - the very
same cells that the virus infects.
“Fascinatingly, DNA maintains its solid-like
state when the conditions are not ideal for
infection, thus stabilising the virus particle
and ensuring that its DNA isn't ejected at the
wrong time. It's here where therapists are
going to look when devising their antiviral
therapies.”
Posted by: Tarun Kumar