Polybromo-1: the chromatin targeting subunit of the PBAF complex

摘要

The human Polybromo-1 protein (Pb1) was recently identified as a unique subunit of the PBAF (Polybromo, Brg1-Associated Factors) chromatin remodeling complex required for kinetochore localization during mitosis and the transcription of estrogen-responsive genes. Pb1 coordinates key features common to all remodeling complexes, including chromatin localization, recruitment of protein subunits and alteration of chromatin architecture. A comprehensive analysis of individual domains composing Pb1 is used to propose new information regarding the function of Pb1 in the PBAF chromatin remodeling complex. The newly identified regulatory role of this important protein is also examined to explain both native function and the emerging role of Pb1 as a tumor suppressor found to be mutated in breast cancer.