FRET probes for analysis of serpin-mediated apoptosis in focal brain ischemia. In light of the profound significance of apoptosis research, it s essential to have probes which can discriminate between different apoptotic pathways. The serine protease- dependent pathway is one of the most recently identified apoptotic programs, which still lacks specific tools for its visualization in situ. Serpin 1B is a key member of this pathway and is an important effector of apoptotic death in neural tissue. In metabolic stress it transforms into an active endonuclease. This unique transition occurs in hypoxia and simultaneously exposes an active DNase site and a nuclear localization signal. The newly formed DNA degrading enzyme promptly moves into the nucleus causing cell death. In spite of the high importance of this non-caspase apoptosis mechanism, there are currently no methods to selectively label it in tissue sections and in live cell cultures. In this project we will develp such methods and will apply them to study serpin-mediated apoptosis in focal brain ischemia.
Specific aims : 1. To develop the new FRET-based approach for selective labeling of serpin-mediated apoptosis in tissue sections. The approach will simultaneously co-detect serpin 1B-derived endonuclease protein and characteristic DNA breaks which it produces. 2. To develop the new FRET-based approach for selective labeling of serpin-mediated apoptosis in live cell cultures. The FRET probes will become fluorescent only after they detect a specific marker of serpin-mediated pathway. 3. To apply the newly developed molecular tools to study focal cerebral ischemia. To evaluate the role of serpin-mediated apoptosis in focal brain ischemia in the rat model; to investigate its initiation mechanisms, dynamics, and patterns of distribution. The project will introduce enabling technologies for apoptosis research in general, and for studies in ischemia in particular. Their first systematic application to focal brain ischemia will provide information useful for the future clinical and research investigations of stroke, and for the development of effective therapeutic interventions.

Public Health Relevance

The proposed project will result in the development of a new technology for the needs of medical diagnostics and pathology. The technology will provide new enabling tools for molecular pathology and cell biology. It will allow precise evaluation of the effects of therapy in diseases such as stroke, as well as various cancers and Alzheimer's disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS082553-03
Application #
9037073
Study Section
Neural Oxidative Metabolism and Death Study Section (NOMD)
Program Officer
Bosetti, Francesca
Project Start
2014-04-01
Project End
2017-03-31
Budget Start
2016-04-01
Budget End
2017-03-31
Support Year
3
Fiscal Year
2016
Total Cost
Indirect Cost
Name
Baylor College of Medicine
Department
Neurosurgery
Type
Schools of Medicine
DUNS #
051113330
City
Houston
State
TX
Country
United States
Zip Code
77030
Minchew, Candace L; Didenko, Vladimir V (2017) Dual Detection of Nucleolytic and Proteolytic Markers of Lysosomal Cell Death: DNase II-Type Breaks and Cathepsin D. Methods Mol Biol 1554:229-236
Didenko, Vladimir V (2017) Express FRET Labeling and Analysis of Phagocytic Clearance. Methods Mol Biol 1644:3-11
Minchew, Candace L; Didenko, Vladimir V (2017) Quick Detection of DNase II-Type Breaks in Formalin-Fixed Tissue Sections. Methods Mol Biol 1644:113-119
Didenko, Vladimir V (2017) Zebra Tail Amplification: Accelerated Detection of Apoptotic Blunt-Ended DNA Breaks by In Situ Ligation. Methods Mol Biol 1644:167-177
Hauser, Paul; Wang, Sha; Didenko, Vladimir V (2017) Apoptotic Bodies: Selective Detection in Extracellular Vesicles. Methods Mol Biol 1554:193-200