RNA is a structural molecule whose three-dimensional architecture stores biological information, interacts with cellular proteins, catalyzes chemical reactions, and coordinates an infectious life cycle. It carries out these actions through precise three-dimensional structures capable of recognizing and binding other molecules with high specificity. What is less widely appreciated is that RNA achieves this wide range of interactions not despite its constant movement, but becau

Dynein is a vastly more complex motor than kinesin. It walks along microtubules carrying vesicles, RNA granules, mitochondria, signaling complexes, and even large full chromosomes. It moves the entire cell nucleus during immune cell movement and manages the extraordinarily complex choreography of chromosome separation during cell division. It is a motor with awareness of what each situation requires. Dynein is enormous. Including its essential additional dynactin complex, i

Since DNA’s discovery, molecular biology had operated on reassuring assumptions: every protein folds into one precise, stable shape; shape determines its function; and shape is determined by a sequence of amino acids produced by a sequence of DNA letters. It was a clean idea. The holy grail of bioscience for decades was finding the shapes of proteins and the DNA codes that determine that shape. It is very difficult to determine the shapes of any protein from the sequence of a

Water is the medium that makes life possible. Water is so ordinary that we rarely think of it as doing anything. But inside a living cell, water is not a passive background—it is an active participant in nearly every molecular event and every cellular structure. The water molecule has a peculiar geometry. One oxygen atom pulls so strongly on two hydrogen atoms that it ends up slightly negative, while the two hydrogens are left slightly positive, which results in four partial