Research Title: Carnitine transporter in human disease

Carnitine is a natural nutrient essential for fatty acid oxidation and its deficiency results in hypoketotic hypoglycemia,
skeletal and heart myopathy, preventable by dietary carnitine. The Novel Organic Cation Transporter 2 (OCTN2) is a high-affinity carnitine transporter and is mutated in primary carnitine deficiency. The objective of this research is to define how mutations identified in patients with primary carnitine deficiency impair the function of this transporter.

To accomplish this objective, the student will identify mutations in new patients with this disorder and reproduce them in mammalian expression vectors using site-directed mutagenesis. The resulting vector is then transfected in Chinese Hamster Ovary Cells and analyzed for function using specialized transport techniques.

To define the function of specific domains of the OCTN2 (carnitine) transporter, we have already constructed recombinant transporters in which specific domains are substituted by similar ones obtained from a transporter (named OCTN1) which does not transport carnitine. The combined analysis of the transporter containing site-directed mutations and of these chimeric OCTN2/OCTN1 transporters should define the role of different domains of the carnitine transporter in mediating solute fluxes and define why certain mutations cause disease in humans.

The student will learn how to extract and work with DNA and RNA, to identify mutations in patients with genetic diseases, to work with recombinant plasmids, and to measure cell functions. The student will also learn the clinical presentation of patients with inherited disorders of fatty acid oxidation and to correlate it with the results obtained in the laboratory to establish genotype-phenotype correlation.

Does this research involve human subjects or animals? on

If yes, what is the protocol number? IRB # 9120

11/2004