Interferon-gamma (IFN-gamma) plays a pivotal role in promoting host defense to a variety of intracellular and extracellular microbial pathogens and neoplastic cells. For the past 12 years my laboratory has focused its efforts on elucidating IFNgamma's molecular mechanism of action and physiologic role in vivo. During the current funding period we cloned and characterized the ligand binding chain of the human and murine IFNgamma receptors (now termed the alpha chain), demonstrated the requirement for a second species matched polypeptide (now termed the beta chain), demonstrated the ligand dependent tyrosine phosphorylation of the IFNgamma receptor alpha chain and defined the mechanism by which IFNgamma receptor alpha chain tyrosine phosphorylation couples the receptor to its signal transduction system. On the basis of this work and work from other laboratories we have formulated a model of IFNgamma signal transduction that involves the following steps: (l) ligand induced assembly of an activated receptor complex (2) activation of receptor associated tyrosine kinases (3) phosphorylation of a specific tyrosine residues in the intracellular domain of the receptor a chain, (4) binding of a latent cytosolic/membrane associated transcription factor known as p9l to the phosphorylated receptor a chain, (5) phosphorylation/activation of p9l by the receptor associated active tyrosine kinases and (6) assembly of an activated p9l containing transcription factor complex that then translocates to the nucleus where it transcriptionally activates IFNgamma inducible genes. The focus of the research proposed in this renewal application is to critically test the model described above and to elucidate at the molecular level the interactions that occur between the IFNgamma receptor subunits and specific pathway components. To accomplish this long range goal we intend to pursue the following three specific aims. I. We will elucidate the structure and function of the human IFNgamma receptor beta chain. Here we will use mutagenesis approaches to identify the structure-function relationships that are operative within the intracellular domain of the IFNgamma receptor beta chain and explore how this region of the molecule participates in the signal transduction process. We will also assess the mechanism by which the beta chain is recruited into the signaling process by ligand. II. We will define in detail the interaction of p9l with the phosphorylated IFNgamma receptor a chain. We intend to finish the description of the interaction by exploring whether p9l can be coprecipitated with the IFNgamma receptor a chain, define whether the interaction of p9l with the phosphorylated receptor a chain occurs directly or requires an adapter protein, and study the structures on p9l (and/or the adapter protein) needed to mediate the interaction. III. We will define the molecular basis of the IFNgamma inducible tyrosine kinase activity. This study will establish the identity of the tyrosine kinase(s) that associate with the IFNgamma receptor alpha chain, define the basis of the specificity of the receptor-kinase associations, and elucidate the mechanism of kinase activation. These studies are certain to provide new insights that will further elucidate the molecular mechanisms underlying IFNgamma's important immunomodulatory and proinflammatory activities.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37CA043059-12
Application #
2608034
Study Section
Allergy and Immunology Study Section (ALY)
Program Officer
Mccarthy, Susan A
Project Start
1986-02-01
Project End
1999-11-30
Budget Start
1997-12-01
Budget End
1998-11-30
Support Year
12
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Washington University
Department
Pathology
Type
Schools of Medicine
DUNS #
062761671
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Chang, Chih-Hao; Qiu, Jing; O'Sullivan, David et al. (2015) Metabolic Competition in the Tumor Microenvironment Is a Driver of Cancer Progression. Cell 162:1229-41
Mittal, Deepak; Gubin, Matthew M; Schreiber, Robert D et al. (2014) New insights into cancer immunoediting and its three component phases--elimination, equilibrium and escape. Curr Opin Immunol 27:16-25
Gubin, Matthew M; Zhang, Xiuli; Schuster, Heiko et al. (2014) Checkpoint blockade cancer immunotherapy targets tumour-specific mutant antigens. Nature 515:577-81
Lee, Sang Hun; Carrero, Javier A; Uppaluri, Ravindra et al. (2013) Identifying the initiating events of anti-Listeria responses using mice with conditional loss of IFN-? receptor subunit 1 (IFNGR1). J Immunol 191:4223-34
Teijaro, John R; Ng, Cherie; Lee, Andrew M et al. (2013) Persistent LCMV infection is controlled by blockade of type I interferon signaling. Science 340:207-11
Kreisel, Daniel; Gelman, Andrew E; Higashikubo, Ryuji et al. (2012) Strain-specific variation in murine natural killer gene complex contributes to differences in immunosurveillance for urethane-induced lung cancer. Cancer Res 72:4311-7
O'Sullivan, Timothy; Saddawi-Konefka, Robert; Vermi, William et al. (2012) Cancer immunoediting by the innate immune system in the absence of adaptive immunity. J Exp Med 209:1869-82
O'Sullivan, Timothy; Dunn, Gavin P; Lacoursiere, Daphne Y et al. (2011) Cancer immunoediting of the NK group 2D ligand H60a. J Immunol 187:3538-45
Winkler, Ashley E; Brotman, Joshua J; Pittman, Meredith E et al. (2011) CXCR3 enhances a T-cell-dependent epidermal proliferative response and promotes skin tumorigenesis. Cancer Res 71:5707-16
Uppaluri, Ravindra; Sheehan, Kathleen C F; Wang, Liqing et al. (2008) Prolongation of cardiac and islet allograft survival by a blocking hamster anti-mouse CXCR3 monoclonal antibody. Transplantation 86:137-47

Showing the most recent 10 out of 60 publications