Cell publishes findings of unusual significance in any area of experimental biology, including but not limited to cell biology, molecular biology, neuroscience, immunology, virology and microbiology, cancer, human genetics, systems biology, signaling, and disease mechanisms and therapeutics. The basic criterion for considering papers is whether the results provide significant conceptual advances into, or raise provocative questions and hypotheses regarding, an interesting and important biological question. In addition to primary research articles in four formats, Cell features review and opinion articles on recent research advances and issues of interest to its broad readership in the Leading Edge section.