From the NYT by
By Knvul Sheikh
Peering inside cells has been an integral part of biology ever since the 17th century, when cells were discovered under a microscope. But even with advances in light and electron microscopy, researchers who want to understand where various molecules are inside a cell — and thus how cells like neurons, immune cells and tumors differ from one another — can glean only so much .
Now, scientists have come up with a new way to capture what’s going on in there. The approach, called DNA microscopy, uses simple chemical reactions essentially to map a cell’s interior, highlighting the contents and indicating exactly where everything can be found.
The technique, described Thursday in the journal Cell, also reveals a wealth of genetic information not accessible with traditional microscopy tools: which immune receptor genes are turned on or off, say, and whether cells are healthy or full of disease-causing mutations.
“DNA microscopy captures both genetic and spatial information simultaneously,” said Joshua Weinstein, a postdoctoral researcher at the Broad Institute of M.I.T. and Harvard and the lead author of the paper. “That’s what’s really beautiful about it.”
A scientist starts by pipetting readily available chemical reagents onto a sample. This causes small, synthetic DNA tags to latch on to biomolecules inside the cells. A subsequent reaction leads each tag to generate copies, which emanate outward like radio signals from a cellphone tower.