Biochemistry, Biophysics, and Structural Biology Commons^™

A Novel Cardiac Function Of Sumo2/3 And Senp5 Dependent Pathway And Its Physiological Impact On Congestive Cardiomyopathy, Eun Young Kim

Dissertations & Theses (Open Access)

A Novel cardiac function of SUMO2/3 and SENP5 dependent pathway and its physiologic impact on congestive cardiomyopathy

Publication No.___________

Eun Young Kim, M.S.

Supervisory professor: Robert J. Schwartz, Ph.D.

SUMOylation regulates diverse cellular processes including transcription, cell cycle, protein stability, and apoptosis. Although SUMO1 has been extensively studied so far, relevance of SUMO2/3 is unclear, especially in heart. Here we show that failing heart induces SUMO2/3 conjugation. Increased SUMO2/3-dependent modification leads to congestive heart disease such as cardiac hypertrophy by promoting cardiac cell death. Calpain2 and Calpastatin as a novel SUMO2 targets have been known to be involved in mitochondrial-independent …

Interaction Between Brk And Her2 In Breast Cancer, Midan Ai

Dissertations & Theses (Open Access)

INTERACTION BETWEEN BRK AND HER2 IN BREAST CANCER

Midan Ai, Ph.D.

Supervisory Professor: Zhen Fan, M.D.

Breast tumor kinase (Brk) is a nonreceptor protein-tyrosine kinase that is highly expressed in approximately two thirds of breast cancers but is not detectable or is expressed at very low levels in normal mammary epithelium. Brk plays important roles in promoting proliferation, survival, invasion, and metastasis of breast cancer cells, but the mechanism(s) of which remain largely unknown. Recent studies showed that Brk is frequently co-overexpressed with human epidermal growth factor receptor-2 (HER2) and is physically associated with HER2 in breast cancer. The mechanism …

Substrate And Regulation Of Mitochondrial Μ-Calpain, Aashish Joshi

University of Kentucky Doctoral Dissertations

μ -Calpain is localized to the mitochondrial intermembrane space. Apoptosisinducing factor (AIF), which executes caspase-independent cell death, is also localized to the mitochondrial intermembrane space. Following processing at the N-terminus, AIF becomes truncated (tAIF) and is released from mitochondria. The protease responsible for AIF processing has not been established. The same submitochondrial localization of mitochondrial μ-calpain and AIF gives support to the hypothesis that mitochondrial μ-calpain may be responsible for processing AIF. Atractyloside-induced tAIF release in rat liver mitochondria was inhibited by cysteine protease inhibitor MDL28170, but not by calpain inhibitors PD150606 or calpastatin. Moreover, μ-calpain immunoreactivity was difficult to …

Engineering Calpastatin To Develop A Sensor To Detect Active Calpain, Lisa M. Vanhooser

Electronic Theses and Dissertations

Calpains, Ca²⁺-activated cysteine proteases are essential for early embryonic development and function in signal transduction, cell adhesion, and apoptosis. Calpains also contribute to cataractogenesis, myocardial infarctions, and neurodegenerative diseases such as Alzheimer's. The various methods currently available to demonstrate these roles do not directly identify spatial or temporal activation of calpain in cells. Therefore, a tool to detect active calpain in situ will be useful. Calpastatin is the ubiquitous, endogenous inhibitor that specifically binds the active conformation of the conventional calpains. Calpastatin consists of four homologous domains each containing three subdomains A, B, and C. The crystal structure …

Development Of An Enzyme-Linked Immunosorbent Assay (Elisa) For Quantification Of Skeletal Muscle Calpastatin, M. E. Doumit, Steven M. Lonergan, J. R. Arbona, J. Killefer, M. Koohmaraie

Steven M. Lonergan

An indirect antibody ELISA was developed for rapid and sensitive quantification of skeletal muscle calpastatin. Polyclonal antibodies were raised in rabbits against recombinant calpastatin, corresponding to domains 2, 3, and 4 of bovine skeletal muscle calpastatin. Western blot analysis revealed that these antibodies specifically recognize an immunoreactive calpastatin protein of approximately 130 kDa in prerigor skeletal muscle extracts. The intensity of the immunoreactive bands corresponds qualitatively with assayable calpastatin activity. For ELISA development, optimum dilutions of sample, primary anti-calpastatin antibody, and peroxidase-conjugated secondary antibody were determined by titration. A dilution optimum for coating of Immulonâ 4 (Dynatech) plates was observed …