The researchers filmed individual HIV particles as they traveled to the nucleus of a human cell and began taking over its genetic machinery -- the first step in the destruction of the body's immune system that leads to AIDS.
The movies not only offer tantalizing glimpses of HIV in action, but provide visual proof that HIV enlists the assistance of its host to wreak havoc on the body's defenses.
The virus can be seen traveling along a part of the host cell's own skeletal framework of microtubules as it makes its way from the outer membrane to the nucleus. The virus hitches a ride aboard a multi-unit protein called dynein, commonly referred to as a molecular motor.
"Dynein is like a tractor trailer, the microtubules are the highway, and the HIV particles are the cargo," said David McDonald, assistant professor of microbiology and immunology at UIC.
McDonald and Thomas Hope, associate professor of microbiology and immunology at UIC, are co-authors of the study, which appeared Nov. 11 in the Journal of Cell Biology. Science magazine named the paper an "editor's choice" in its Nov. 22 issue, and it will be featured in an upcoming issue of Nature Cell Biology.
An editorial accompanying the paper said, "With the powerful approaches developed by McDonald et al. and the incredible progress in imaging single fluorescent molecules in living cells, ... important and fascinating questions of HIV cell biology can now be addressed."
Until recently, little was known about how HIV enters a cell. The virus is made of an outer shell, or envelope, and a core, referred to as a particle, which is composed of proteins and genetic material. When the virus attacks an immune cell, it fuses with the cell's membrane and releases its particl
Contact: Sharon Butler
University of Illinois at Chicago