Natasha Zachara, Ph.D.

Natasha Zachara, Ph.D.

Associate Professor

410-955-7049

Research in the Zachara Lab

The modification of nuclear, cytoplasmic, and mitochondrial proteins by O-linked beta-N-acetylglucosamine (O-GlcNAc) is an essential post-translational modification common in metazoans. O-GlcNAc is cycled on and off proteins in response to environmental and physiological stimuli impacting protein function, which, in turn, tunes pathways that include transcription, translation, proteostasis, signal transduction, and metabolism. In 2004 we demonstrated that O-GlcNAcylation of intracellular proteins was a novel regulator of cell survival and a modulator of the cellular stress response. In response to diverse forms of cellular stress, the O-GlcNAc modification is increased on myriad proteins. Elevation of O-GlcNAc levels prior to or after the induction of injury promotes cell survival in models of heat stress, hypoxia, oxidative stress, ischemia reperfusion injury, and trauma hemorrhage. Together, these data suggest that modification of proteins by O-GlcNAc in an integral component of the cellular stress response.

Our current work aims to define the mechanisms by which O-GlcNAc regulates cell survival in diverse models, understand how these mechanisms are dysregulated in disease, and to harness this information with the goal of improving patient outcomes. To identify key O-GlcNAcylated proteins that regulate cell survival decisions, we have used quantitative proteomics to define the O-GlcNAcome of cells subjected to heat or oxidative stress (Zachara et al., 2011; Lee et al., 2016). These and other studies showed that O-GlcNAc inhibits GSK3β leading to enhanced heat shock protein expression (Kazemi et al., 2010) and that O-GlcNAc regulates DNA damage response pathways (Zhong et al., 2015). In complimentary work, we are focused on understanding the mechanisms that regulate the enzymes and metabolites essential for O-GlcNAc-cycling (Narayanan et al., 2023). This work encompasses changes in physiology (sex), signaling (injury), and disease (mutation). To this end, we have characterized tools (Groves and Zachara, 2017, Narayanan, Zahra et al., 2023) and streamlined approaches that enable quantitative assessment of enzymatic activity and enzyme-protein interactors (Groves et al., 2017; Martinez et al., 2021).

Biography

Natasha Zachara Ph.D. (Citations: 6442; H-index: 37; i10-index: 54)

Dr. Natasha Zachara is an Associate Professor of Biological Chemistry and Oncology at the Johns Hopkins School of Medicine. Dr. Zachara received her undergraduate degree in biotechnology (with honors) from Macquarie University in Sydney, Australia. Her dissertation, completed at Macquarie University, focused on developing new technologies to map and quantify site-specific changes in protein glycosylation. She completed postdoctoral studies in glycobiology at the Johns Hopkins University School of Medicine. Dr. Zachara joined the Johns Hopkins faculty in 2007. Currently, she is the Director of the K12 training program “Immersive Training in the Glycosciences”, Chair of the “Glycan Advisory Committee”, a Director of the “Society for Glycobiology”, and an Associate Editor of the Biochemical Journal.

Current Zachara Lab Members

  • Fiddia Zahra, Graduate Student
  • Akanksha Aggarwal, Graduate Student
  • Megan Craven, Undergraduate Student
  • Sandra Fahmy, Undergraduate Student

Recent and Key Citations:

  • Narayanan B, Sinha P, Henry R, Reeves RA, Paolocci N, Kohr MJ, Zachara NE. Cardioprotective O-GlcNAc-Signaling is Elevated in Murine Female Hearts via Enhanced O-GlcNAc Transferase Activity. J Biol Chem. 2023 Nov 8:105447. PMID: 37949223.
  • Narayanan B, Zahra F, Reeves RA, Aggarwal A, O’Meally RN, Henry R, Craven M, Jacobson A, Cole RN, Kohr M, Umapathi P, Zachara NE. Differential Detection of O-GlcNAcylated proteins in the heart using antibodies. Anal Biochem. 2023 Jul 26:115262. doi: 10.1016/j.ab.2023.115262. Epub ahead of print. PMID: 37507081.
  • Martinez M, Renuse S, Kreimer S, O’Meally R, Natov P, Madugundu AK, Nirujogi RS, Tahir R, Cole R, Pandey A, Zachara NE. Quantitative Proteomics Reveals that the OGT Interactome Is Remodeled in Response to Oxidative Stress. Mol Cell Proteomics. 2021 Mar 12;20:100069. PMID: 33716169; PMCID: PMC8079276.
  • Mesubi OO, Rokita AG, Abrol N, Wu Y, Chen B, Wang Q, Granger JM, Tucker-Bartley A, Luczak ED, Murphy KR, Umapathi P, Banerjee PS, Boronina TN, Cole RN, Maier LS, Wehrens XH, Pomerantz JL, Song LS, Ahima RS, Hart GW, Zachara NE, Anderson ME. Oxidized CaMKII and O-GlcNAcylation cause increased atrial fibrillation in diabetic mice by distinct mechanisms. J Clin Invest. 2021 Jan 19;131(2):e95747. PMID: 33151911; PMCID: PMC7810480.
  • Umapathi P, Mesubi OO, Banerjee PS, Abrol N, Wang Q, Luczak ED, Wu Y, Granger JM, Wei AC, Reyes Gaido OE, Florea L, Talbot CC Jr, Hart GW, Zachara NE, Anderson ME. Excessive O-GlcNAcylation Causes Heart Failure and Sudden Death. Circulation. 2021 Apr 27;143(17):1687-1703. PMID: 33593071; PMCID: PMC8085112.
  • Groves JA, Maduka AO, O’Meally RN, Cole RN, Zachara NE. Fatty acid synthase inhibits the O-GlcNAcase during oxidative stress. J Biol Chem. 2017 Apr 21;292(16):6493-6511. PMID: 28232487; PMCID: PMC5399103.
  • Zhong J, Martinez M, Sengupta S, Lee A, Wu X, Chaerkady R, Chatterjee A, O’Meally RN, Cole RN, Pandey A, Zachara NE. Quantitative phosphoproteomics reveals crosstalk between phosphorylation and O-GlcNAc in the DNA damage response pathway. Proteomics. 2015 Jan;15(2-3):591-607. PMID: 25263469; PMCID: PMC4564869.
  • Lee A, Miller D, Henry R, Paruchuri VD, O’Meally RN, Boronina T, Cole RN, Zachara NE. Combined Antibody/Lectin Enrichment Identifies Extensive Changes in the O-GlcNAc Sub-proteome upon Oxidative Stress. J Proteome Res. 2016 Dec 2;15(12):4318-4336. PMID: 27669760.
  • Zachara NE, Molina H, Wong KY, Pandey A, Hart GW. The dynamic stress-induced “O-GlcNAc-ome” highlights functions for O-GlcNAc in regulating DNA damage/repair and other cellular pathways. Amino Acids. 2011 Mar;40(3):793-808. PMID: 20676906; PMCID: PMC3329784.
  • Kazemi Z, Chang H, Haserodt S, McKen C, Zachara NE. O-linked beta-N-acetylglucosamine (O-GlcNAc) regulates stress-induced heat shock protein expression in a GSK-3beta-dependent manner. J Biol Chem. 2010 Dec 10;285(50):39096-107. PMID: 20926391; PMCID: PMC2998145.
  • Zachara NE, O’Donnell N, Cheung WD, Mercer JJ, Marth JD, Hart GW. Dynamic O-GlcNAc modification of nucleocytoplasmic proteins in response to stress. A survival response of mammalian cells. J Biol Chem. 2004 Jul 16;279(29):30133-42. PMID: 15138254.

A complete list of publications: https://www.ncbi.nlm.nih.gov/myncbi/natasha.zachara.1/bibliography/public/.