Volume 10 Issue 10, October 2003

Recent studies of a tRNA guanine transglycosylase—a modifying enzyme known in all kingdoms of life—show how an unexpected active site aspartate becomes covalently attached to the tRNA substrate during catalysis, and how subsequent base exchange occurs in a single active site.

Four recent studies demonstrate that closing of a cleft in the myosin head is required for actin binding and nucleotide release. This represents a major breakthrough in understanding actomyosin-based motility.

The Hindu goddess Maha Devi is represented as having the power both to make and to destroy. Reminiscent of such power, two recent studies highlight the roles that nucleases play in both making and destroying RNAs associated with the mysterious world of small RNAs.

What prevents the replisome complex from moving along the DNA or breaking down when the replication fork stalls or encounters a DNA lesion? A recent paper describes how checkpoint proteins, Mrc1 and Tof1 couple the replisome to DNA synthesis.