The innate immune system senses non-self nucleic acids via germ-line encoded pattern recognition receptors. RNA is sensed via Toll-like receptor (TLR)-3, -7 and -8 or by the cytoplasmic RNA helicases RIG-I and MDA-5. Little is known about sensors for cytoplasmic DNA, which when delivered to the cytoplasm trigger type I IFN gene transcription and caspase-1-mediated processing of IL-12. We have identified PISA (PYHIN protein stimulating ASC), one of four human PYHIN proteins as a receptor for cytosolic DNA. The HIN200 domain of PISA binds to DNA, while the PYD domain (but not that of PYHIN1-3) associates with the adapter molecule ASC to activate NF-:B and caspase-1. Knockdown of PISA downregulates caspase-1-mediated IL-12 responses, with concomitant increases in type I interferon production. Our hypothesis is that PISA serves to recognize microbial cytosolic DNA (such as bacterial or viral DNA) and that PISA induces pro-inflammatory responses towards cytoplasmic DNA via the assembly of an inflammasome that engages ASC and caspase-1. In this study, we propose to further characterize the role of PISA in the recognition of viral and bacterial cytosolic DNA. We will also generate a PISA knock-out mouse by gene-trap technology and/or targeted gene deletion and propose to analyze the in vivo relevance of PISA for microbial infections. Finally, we will assess the role of PISA for the modulation of interferon responses towards cytoplasmic DNA. Elucidation of the molecular mechanisms of cytosolic DNA recognition could lead to novel therapeutic targets for microbial infections and thereby enable novel strategies that could prevent inflammatory reactions to gene therapy approaches. Public Health Relevance: Pathogens are detected by receptors expressed in different areas of cells of the immune system. This grant is focused on understanding how a cytosolic protein, which we have identified called PISA (PYHIN protein stimulating ASC) senses pathogens by virtue of their DNA. Elucidation of molecular details of PISA activation could lead to novel strategies of pharmacological interference for diseases based on intracellular DNA recognition.

Public Health Relevance

Pathogens are detected by receptors expressed in different areas of cells of the immune system. This grant is focused on understanding how a cytosolic protein, which we have identified called PISA (PYHIN protein stimulating ASC) senses pathogens by virtue of their DNA. Elucidation of molecular details of PISA activation could lead to novel strategies of pharmacological interference for diseases based on intracellular DNA recognition.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI083713-05
Application #
8493774
Study Section
Immunity and Host Defense Study Section (IHD)
Program Officer
Palker, Thomas J
Project Start
2009-07-01
Project End
2014-06-30
Budget Start
2013-07-01
Budget End
2014-06-30
Support Year
5
Fiscal Year
2013
Total Cost
$378,883
Indirect Cost
$148,559
Name
University of Massachusetts Medical School Worcester
Department
Type
Organized Research Units
DUNS #
603847393
City
Worcester
State
MA
Country
United States
Zip Code
01655
Schattgen, Stefan A; Gao, Guangping; Kurt-Jones, Evelyn A et al. (2016) Cutting Edge: DNA in the Lung Microenvironment during Influenza Virus Infection Tempers Inflammation by Engaging the DNA Sensor AIM2. J Immunol 196:29-33
Baum, Rebecca; Sharma, Shruti; Organ, Jason M et al. (2016) STING regulates abnormal bone formation induced by deficiency of DNase II. Arthritis Rheumatol :
Pawaria, Sudesh; Sharma, Shruti; Baum, Rebecca et al. (2016) Taking the STING out of TLR-driven autoimmune diseases: good, bad, or indifferent? J Leukoc Biol :
Baum, Rebecca; Nündel, Kerstin; Pawaria, Sudesh et al. (2016) Synergy between Hematopoietic and Radioresistant Stromal Cells Is Required for Autoimmune Manifestations of DNase II-/-IFNaR-/- Mice. J Immunol 196:1348-54
Bronner, Denise N; Abuaita, Basel H; Chen, Xiaoyun et al. (2015) Endoplasmic Reticulum Stress Activates the Inflammasome via NLRP3- and Caspase-2-Driven Mitochondrial Damage. Immunity 43:451-62
Sun, Chenglong; Schattgen, Stefan A; Pisitkun, Prapaporn et al. (2015) Evasion of innate cytosolic DNA sensing by a gammaherpesvirus facilitates establishment of latent infection. J Immunol 194:1819-31
Broderick, Lori; De Nardo, Dominic; Franklin, Bernardo S et al. (2015) The inflammasomes and autoinflammatory syndromes. Annu Rev Pathol 10:395-424
Pawaria, Sudesh; Moody, Krishna L; Busto, Patricia et al. (2015) An unexpected role for RNA-sensing toll-like receptors in a murine model of DNA accrual. Clin Exp Rheumatol 33:S70-3
Vanaja, Sivapriya K; Rathinam, Vijay A K; Fitzgerald, Katherine A (2015) Mechanisms of inflammasome activation: recent advances and novel insights. Trends Cell Biol 25:308-15
Baum, Rebecca; Sharma, Shruti; Carpenter, Susan et al. (2015) Cutting edge: AIM2 and endosomal TLRs differentially regulate arthritis and autoantibody production in DNase II-deficient mice. J Immunol 194:873-7

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