Cloning and characterization of canine prostate-specific membrane antigen
Article first published online: 28 JAN 2013
Copyright © 2013 Wiley Periodicals, Inc.
Volume 73, Issue 6, pages 642–650, May 2013
How to Cite
Schmidt, S., Fracasso, G., Colombatti, M. and Naim, H. Y. (2013), Cloning and characterization of canine prostate-specific membrane antigen. Prostate, 73: 642–650. doi: 10.1002/pros.22605
- Issue published online: 4 APR 2013
- Article first published online: 28 JAN 2013
- Manuscript Accepted: 24 SEP 2012
- Manuscript Received: 22 AUG 2012
- University of Verona
- Verona Nanomedicine Initiative
- Progetto Regione Veneto
- prostate cancer
Prostate-specific membrane antigen (PSMA) is a promising biomarker in the diagnosis of prostate cancer and a potential target for antibody-based therapeutic strategies. We isolated the canine PSMA cDNA and investigated the cellular and biochemical characteristics of the recombinant protein as a potential target for animal preclinical studies of antibody based-therapies.
Canine PSMA cDNA was isolated by PCR, cloned into expression vectors and transfected into COS-1 and MDCK cells. The biosynthesis and glycosylation of the recombinant protein were investigated in pulse-chase experiments, the cellular localization by confocal laser microscopy, the mode of association of PSMA with the membrane with solubilization in different detergents and its quaternary structure in sucrose-density gradients.
Canine PSMA shows 91% amino acid homology to human PSMA, whereby the major difference is a longer cytoplasmic tail of canine PSMA compared to its human counterpart. Canine PSMA is trafficked efficiently along the secretory pathway, undergoes homodimerization when it acquires complex glycosylated mature form. It associates with detergent-resistant membranes, which act as platforms along its intracellular trafficking. Confocal analysis revealed canine PSMA at the cell surface, Golgi, and the endoplasmic reticulum. A similar distribution is revealed for human PSMA, yet with reduced cell surface levels.
The cloning, expression, biosynthesis, processing and localization of canine PSMA in mammalian cells is described. We demonstrate that canine PSMA reveals similar characteristics to human PSMA rendering this protein useful as a translational model for investigations of prostate cancer as well as a suitable antigen for targeted therapy studies in dogs. Prostate 73: 642–650, 2013. © 2012 Wiley Periodicals, Inc.