My long-term career goals focus on developing novel therapeutic approaches for patients with hemoglobinopathies with my research and clinical experiences serving as the inspiration for this goal. This mentored career development award (CDA) will help me attain the laboratory and career development skills necessary to achieve research independence through the combination of rigorous laboratory work, didactic sessions, and through my outstanding mentor and advisory committee. I will conduct the proposed studies under the outstanding mentorship of Dr. Gerd Blobel, an international leader in epigenetic gene regulation in hematopoiesis. Additionally, my advisory committee of Drs. Mortimer Poncz, Stephen Liebhaber, and Stefano Rivella are all experts in their respective fields with experience in every facet of my research strategy and career development plan. The Children's Hospital of Philadelphia and the University of Pennsylvania provide an ideal setting for a young investigator to develop providing state-of-the art facilities, equipment, and cores along with internationally recognized faculty across all disciplines. My project will focus on broadening the applicability of forced chromatin looping, a technique developed in our laboratory whereby tethering the looping factor Ldb1 to a specified genomic location through the use of custom designed sequence specific binding protein allows for competition for enhancer bound Ldb1 and concomitant alteration in the higher-order chromatin structure (looping) resulting in remarkable transcriptiona activation of the target gene. We demonstrated in the -globin locus that we could override developmental repression of the fetal ?-globin gene resulting in therapeutically relevant levels o fetal hemoglobin. We hypothesize that is approach can be broadly applied to any locus containing an enhancer that binds Ldb1. In this proposal, we will investigate the ?-globin locus. Overcoming the developmentally repressed embryonic ?-globin gene can ameliorate the phenotype of ?-thalassemia and therefore I propose to (1) design ?-globin promoter sequence specific binding proteins to recruit Ldb1 to the ?-globin promoter that will effectively compete with Ldb1 bound to the ?-globin enhancer, HS40, enabling expression of this normally silent gene in adult erythroid cells, (2) to extensively dissect the mechanism of action to gain a deeper appreciation of the mechanism of forced chromatin looping, and (3) conduct proof-of-principle studies that forced chromatin looping in the ?-globin locus can ameliorate the phenotype of preclinical models of ?-thalassemia. Successful development of these laboratory strategies will establish forced chromatin looping as a new therapeutic approach for patients with ?-thalassemia and demonstrate that it has wide application to other enhancer driven loci. Through this CDA I will develop not only this project independent of Dr. Blobel's work, but will gain the skills necessary for its clinical advancement and establish myself as an independent investigator and leader in the field of hemoglobinopathy research.
Patients with severe forms of a specific type of disorder in their red blood cells, ?-thalassemia, have limited therapeutic options outside of bone marrow transplants and life-long blood transfusion, both of which are associated with significant side effects. Here, I am proposing to develop a novel treatment for this group of patients using a unique approach of manipulating the structure of DNA. Additionally, I hope to show that this approach has to potential to treat other types of diseases in a similar fashion.
