Identifying Novel Cardiomyopathy Genes Using Drosophila melanogaster

Abstract

Traditional Drosophila hearts screens have focused on early patterning and development, and adult heart phenotypes have only recently been pursued due to difficulty in accurately measuring cardiac function in adult Drosophila. For my dissertation I performed a screen in Drosophila using optical coherence tomography (OCT) to phenotype cardiac function in awake, adult Drosophila, in order to discover novel disease-causing and disease-modifying genes for heart failure. I initiated a screen of X chromosome deficiency stocks for mutants displaying abnormal cardiac function in the adult, and I identified two mutant strains from the X chromosome with the phenotype of dilated cardiomyopathy. These deficiencies of 125kb and 92kb each correspond to 10 and 16 deleted genes in each, respectively. Interestingly, the candidate genes did not include any sarcomeric proteins, nor any proteins previously implicated in heart function. Utilizing genetic tools including customized deletions, RNAi constructs, and transgenic rescues, I identified the causative gene in each deficiency. I show that cardiomyopathic genes can be identified in adult Drosophila using genetics and noninvasive phenotyping methodologies.