The major interest of our lab is in the area of functions, mechanisms of action, and regulations of histone deacetylases (HDACs). In addition to the work on HDACs in transcriptional co-repressor complexes, we discovered that HDACs regulate important biological processes beyond histone modification. For example, we found that SIRT1 deacetylates and regulates the function of the NBS1 protein, and the Class II deacetylase HDAC6 modifies cortactin and regulates cell movement. This work lays the foundation and places us in a unique position to further address many of the questions raised in this field. Ultimately, this work will provide not only tremendous insight into the novel functions and mechanisms of action of HDACs but also potential diagnostic and therapeutic approaches for the treatment of diseases.