Molecular biology

Species gain and shed startling amounts of DNA as they evolve, and even genomes that look stable churn furiously. What does it mean?

Mathematical insights into how RNA helps viruses pull together their protein shells could guide future studies of viral behavior and function.

Sex might help natural selection purge excessive mistakes from our genes.

New techniques expose unexpected diversity within seemingly uniform tissues.

The proteins that unravel as the temperature starts to rise turn out to be among the most vital.

Without viruses, we might never have evolved.

Proteins work like rigid keys to activate cellular functions — or so everyone thought. Scientists are discovering a huge number of proteins that shape-shift to do their work, upending a century-old maxim of biology.

A virus that causes crippling birth defects has been shown to do something else: It changes thousands of messages coming from DNA that control normal cellular activities.

A new look at the reasons why organisms missing pairs of genes sometimes do much better than normal.