Neurogenetics, Development and Evolution





  Alessandra d'Azzo, Ph.D.

ALESSANDRA D'AZZO, Ph.D.

Member
Genetics / Tumor Cell Biology
St. Jude Children's Research Hospital
Affiliated Professor
Department of Anatomy and Neurobiology
The University of Tennessee College of Medicine

Address

St. Jude Children's Research Hospital
Department of Genetics
Memphis, TN 38105

Education

Ph.D. Institution: University of Milano, Milan Italy; Erasmus University, Rotterdam, The Netherlands

Research Interests

The primary scope of this research program is to elucidate the fundamental role of the lysosomal system in normal cellular metabolism and in pathological conditions associated with lysosomal storage disorders (LSD).

Using a combination of molecular, genetic, and biochemical approaches, they have identified a multiprotein complex of three lysosomal hydrolases: protective protein/cathepsin A (PPCA), -galactosidase (-Gal), and neuraminidase (Neur). In the complex, PPCA (a serine carboxypeptidase) directly associates with the two glycosidases, a configuration needed for their intracellular routing, lysosomal activity, and stability. Three genetically distinct, human neurodegenerative LSD are caused by either single or combined deficiency of these enzymes: galactosialidosis, GM1-gangliosidosis, and sialidosis. To date, there is no effective therapy for these diseases. Using both in vitro systems and laboratory animals, they investigate the cell-specific expression and regulation of these enzymes, their intracellular trafficking, mode/site of association and activation, and their interaction with the substrates they cleave. They are also developing new therapeutic strategies in animal models for the future treatment of patients with these LSD. Greater knowledge of the function of these and other lysosomal proteins in the normal lysosome, as well as a better understanding of the structural and biochemical basis of the diseases, will aid in the design of new drugs and therapies.

The experimental approaches include: generation and characterization of knockout and transgenic mice; correction of affected mice by transplantation with transgenic over expressing or retrovirally transduced bone marrow; expression and regulation of normal and mutant enzymes in prokaryotic/eukaryotic cell systems; and crystal structure determination of over expressed proteins.

Links

St Jude Faculty - Alessandra d'Azzo

Recent Publications

  • Starcher B, d'Azzo A, Keller PW, Rao GK, Nadarajah D, Hinek A. Neuraminidase-1 is required for the normal assembly of elastic fibers. Am J Physiol Lung Cell Mol Physiol. 2008 Oct;295(4):L637-47. Epub 2008 Aug 8. PMID: 18689602
  • Yogalingam G, Bonten EJ, van de Vlekkert D, Hu H, Moshiach S, Connell SA, d'Azzo A. Neuraminidase 1 is a negative regulator of lysosomal exocytosis. Dev Cell. 2008 Jul;15(1):74-86. PMID: 18606142
  • Caciotti A, Donati MA, d'Azzo A, Salvioli R, Guerrini R, Zammarchi E, Morrone A. The potential action of galactose as a "chemical chaperone": Increase of beta galactosidase activity in fibroblasts from an adult GM1-gangliosidosis patient. Eur J Paediatr Neurol. 2008 Jun 19; [Epub ahead of print] PMID: 18571950
  • Elliot-Smith E, Speak AO, Lloyd-Evans E, Smith DA, van der Spoel AC, Jeyakumar M, Butters TD, Dwek RA, d'Azzo A, Platt FM. Beneficial effects of substrate reduction therapy in a mouse model of GM1 gangliosidosis. Mol Genet Metab. 2008 Jun;94(2):204-11. Epub 2008 Apr 1. PMID: 18387328
  • Hermo L, Korah N, Gregory M, Liu LY, Cyr DG, D'Azzo A, Smith CE. Structural alterations of epididymal epithelial cells in cathepsin A-deficient mice affect the blood-epididymal barrier and lead to altered sperm motility. J Androl. 2007 Sep-Oct;28(5):784-97. Epub 2007 May 23. PMID: 17522420
  • Denny CA, Alroy J, Pawlyk BS, Sandberg MA, d'Azzo A, Seyfried TN. Neurochemical, morphological, and neurophysiological abnormalities in retinas of Sandhoff and GM1 gangliosidosis mice. J Neurochem. 2007 Jun;101(5):1294-302. Epub 2007 Apr 17. PMID: 17442056
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