B Cells, Chromatin, DNA Repair, Immune Deficiency, Immunology, Leukemia, Lymphoma, Molecular Biology, T Cells, V(D)J recombination
PhD, UMDNJ Robert Wood Johnson Medical School
Mechanism and Regulation of Immunoglobulin Genes Rearrangements
My laboratory studies the processes of V(D)J recombination and Non-Homologous End Joining (NHEJ). We investigate the factors that control the activity of the Recombination Activating Genes 1 and 2, as well as the protein-protein interactions and mechanisms that determine optimal enzymatic activity during the processing and repair phases of V(D)J recombination. The role of deregulated V(D)J recombination and NHEJ in the etiology of immunodeficiency and cancer are also a major focus of our lab. To address these questions we have used biochemical and molecular biology approaches.
Future directions include the development of in vitro and in vivo model systems to test the various hypotheses generated from our current work. We will continue investigating the mechanism and regulation of the various steps of V(D)J recombination and NHEJ. In addition, our recent findings suggest the participation of new proteins in V(D)J recombination. Their contribution to orchestrate efficient and regulated recombination as well as their potential role in immunodeficiency is under investigation.
Currently we are developing the following projects:
1. Mechanism and regulation of V(D)J repair
2. Biochemical and functional analysis of Artemis.
3. Regulation of V(D)J recombination by Rag2 C-terminus.
4. Mechanisms of V(D)J mediated immunodeficiency.
Vidyasagar Malashetty Ph.D., Post-doctoral Fellow
Shruti Malu Ph.D., Post-doctoral Fellow
Dailia Francis, MSTP student
Lacey Kressin, Master student
Mary Hanna MSc., Research Assistant
1. Couedel, C., Roman, C., Jones, A., Vezzoni, P., Villa, A., and Cortes, P. (2010). Analysis of mutations from SCID and Omenn syndrome patients reveal the central role of the Rag2 PHD domain in regulating V(D)J recombination. J. Clin. Invest. 120, 1337-1344.
2. Matangkasombut, P., Pichavant, M., Saez, D.E., Giliani, S., Mazzolari, E., Finocchi, A., Villa, A., Cortes, P., Umetsu, D.T., and Notarangelo, L. (2008). Lack of iNKT cells in patients with combined immune deficiency due to hypomorphic RAG mutations. Blood 111, 271-274.
3. West, K.L., Singha, N.C., De Ioannes, P., Lacomis, L., Erdjument-Bromage, H. Tempst, P., and Cortes, P. (2005). A direct interaction between RAG2 C-terminus and the core histones is required for VH to DJH recombination. Immunity. 23, 203-212.
4. Sawchuk, D. J., Mansilla-Soto, J., Alarcon, C., Singha, N. C., Langen, H., Bianchi, M.E., Lees-Miller, S. P., Nussenzweigh, M. C., and Cortes, P. (2004). Ku70/80 and DNA-PKcs modulate RAG-mediated cleavage. Implications for the enforcement of the 12/23 rule. JBC, 279, 29821-29831.
5. Mansilla-Soto, J., and Cortes, P. (2003). Commentary. VDJ Recombination: Artemis and Its In Vivo Role in Hairpin Opening. J. Exp. Med. 197, 543-547.
6. Villa, A., Sobacchi, C., Notarangelo, L. D., Bozzi, F., Abinum, M., Abrahamsen, T. G., Arkwright, PD., Baniyash, M., Brooks, EG, Conley, ME., Cortes, P., Duse, M., Fasth, A., Filipovich, AM, Infante, AJ., Jones, A., Mazzolari, E., Muller, SM., Pasic, S., Rechavi, G., Sacco, MG., Santagata, S., Schroeder, ML., Seger, R., Strina, D., Ugazio, A., Valiaho, J., Vihinen, M., Vogler, LB., Ochs, H., Vezzoni, P., Friedrich, W., Schwarz, K. (2001). V(D)J recombination defects in lymphocytes due to RAG mutations: severe immunodeficiency with a spectrum of clinical presentations. Blood 97, 81-88
7. Santagata, S., Villa, A., Sobacchi, C., Cortes, P., and Vezzoni, P. (2000). The genetic and biochemical basis of Omenn syndrome. Immunolol. Rev. 178, 64-74.
8. Santagata, S., Gomez, C. A., Sobacchi, C., Bozzi, F., Abinum, M., Pasic, S., Cortes, P., Vezzoni, P., and Villa, A. (2000). N-terminal RAG1 frameshift mutations in Omenn’s syndrome: internal methionine usage leads to partial V(D)J recombination activity and reveals a fundamental role in vivo for the N-terminal domains. Proc. Natl. Acad. Sci. USA 19, 14572-14577.
9. Gomez, C. A., Ptaszek, L. M., Villa, A., Bozzi, F., Sobacchi, C., Brooks, E. G., Notarangelo, L. D., Spanopoulou, E., Pan, Z-Q., Vezzoni, P., Cortes, P., and Santagata, S. (2000). Mutations in conserved regions of the predicted RAG2 kelch repeats blok initiation of V(D)J recombination and result in primary immunodeficiencies. Mol. Cell Biol. 15, 5653-5664.
10. Santagata, S., Besmer, E., Villa, A., Bozzi, F., Allingham, J., Sobacchi, C., Haniford, D., Vezzoni, P., Nussenzweig, M., Pan, Z-Q., and Cortes, P. (1999). The RAG1/RAG2 complex constitues a 3’ flap endonuclease: implications for junctional diversity in V(D)J and transpositional recombination. Molecular Cell 4, 935-947.
11. Besmer, E., Mansilla-Soto, J., Cassard, S., Sawchuk, D., Brown, g., Sadofsky, M., Lewis, S., Nussenzweig, M., and Cortes, P. (1998). Hairpin coding end opening is mediated by RAG1 and RAG2 proteins. Molecular Cell. 2, 817-828.
12. Weis-Garcia, F., Besmer, E., Yu, W., Sawchuk, D., Hu, Y., Nussenzweig, M., and Cortes, P. (1997). V(D)J recombination: in vitro coding joint formation. Mol. Cel. Biol. 17, 6379-6385.
13. Sawchuk, D., Weis-Garcia, F., Malik, S., Besmer, E., Bustin, M., Nussenzweig, M., and Cortes, P. (1997). V(D)J recombination: Modulation of RAG1 and RAG2 cleavage activity on 12/23 substrates by whole cell extract and DNA-binding proteins. J. Exp. Med. 185, 2025-2032.