Chromatin marks and machines, the missing nucleosome is a theme: gene regulation up and downstream.

A remarkable insight to emerge from chromatin immunoprecipitation studies is that the steps leading to chromatin remodeling and preinitiation complex (PIC) assembly differ significantly, depending upon the gene and its biological context (Cosma, 2002). However, when multiple systems are compared, the differences illuminate checkpoints and generalities that provide insights into the most salient features of mechanism. This concept dominated presentations at the 2004 Chromatin and Transcription by RNA Polymerase II meeting held at the Lake Tahoe Granlibakken Conference Center.