The diversity of distinct covalent forms of proteins (the proteome) greatly exceeds the number of proteins predicted by DNA coding capacities owing to directed posttranslational modifications. Enzymes dedicated to such protein modifications include 500 human protein kinases, 150 protein phosphatases, and 500 proteases. The major types of protein covalent modifications, such as phosphorylation, acetylation, glycosylation, methylation, and ubiquitylation, can be classified according to the type of amino acid side chain modified, the category of the modifying enzyme, and the extent of reversibility. Chemical events such as protein splicing, green fluorescent protein maturation, and proteasome autoactivations also represent posttranslational modifications. An understanding of the scope and pattern of the many posttranslational modifications in eukaryotic cells provides insight into the function and dynamics of proteome compositions.

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pus oocytes contained 7-11 zinc ions per protein, 21 led to the proposal that each 30-amino acid sequence bound one zinc ion through the conserved cysteine and histidine residues. This hypothesis was supported by limited proteolysis studies that yielded fragments differing in length by about 3 kDa, 21 suggesting that these proposed metal-binding units form individually folded, structurally stable domains.The nature of the metal binding sites in TFIIIA was directly probed by X-ray absorption spectroscopic methods. EXAFS analysis of the TFIIIA-5S RNA complex isolated from immature Xenopus oocytes was consistent with the proposed coordination with two sulfur atoms at 2.30 Å and two nitrogen atoms at 2.00 Å. 23 These distances matched reasonably closely those observed for zinc model complexes prepared by Koch and co-workers. 24,25 Zinc Finger Domain Peptides with Naturally Occurring SequencesThe zinc finger hypothesis suggested a reductionist approach to the characterization of these domains. Derek Jantz was born in Littleton, Colorado, and graduated from the University of Colorado at Boulder (B.A. 1996). He received his Ph.D. from the Johns Hopkins University School of Medicine in 2003 under the direction of Jeremy Berg. His research concerned the DNA-binding characteristics of designed Cys 2 His 2 zinc finger proteins. He is presently working as a Postdoctoral Fellow with Homme Hellinga at Duke University Medical Center, focusing on computational protein design. He was selected as graduate student speaker at his graduation from Johns Hopkins, where he described graduate school as "the best period of indeterminate length of my life". Barbara T. Amann was born and raised in Swarthmore, Pennsylvania. She received her B.A. in chemistry from Mt. Holyoke College in 1983. She developed an interest in bioinorganic chemistry at the Pennsylvania State University, where she received her Ph.D. working with Bill Horrocks on lanthanide substitution of the calcium-binding protein calmodulin. In 1988, she joined Jeremy Berg's laboratory as a Postdoctoral Fellow in the Chemistry Department of Johns Hopkins University. She moved with the Berg laboratory to the Department of Biophysics and Biophysical Chemistry at Johns Hopkins School of Medicine and became a Research Associate. In this position, she has studied a range of zinc-binding domains, primarily by NMR, and has run the NMR facility of the department. She has enjoyed teaching other researchers NMR methods and assisting them with their projects. She loves spending time with her husband, two children, dog, and snake. Gregory J. Gatto, Jr., was raised in East Brunswick, New Jersey. He received his A.B. in chemistry in 1994 from Princeton University, where he worked in the laboratory of Martin F. Semmelhack. In the spring of 2003, he received his M.D. and Ph.D. degrees from Johns Hopkins University School of Medicine. There, he worked in the laboratory of Jeremy Berg on the structural biology of designed zinc finger proteins and the molecular details of peroxisomal targeting sig...

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A growing body of evidence suggests that the alpha7 neuronal nicotinic receptor (NNR) subtype is an important target for the development of novel therapies to treat schizophrenia, offering the possibility to address not only the positive but also the cognitive and negative symptoms associated with the disease. In order to probe the relationship of alpha7 function to relevant behavioral correlates we employed TC-5619, a novel selective agonist for the alpha7 NNR subtype. TC-5619 binds with very high affinity to the alpha7 subtype and is a potent full agonist. TC-5619 has little or no activity at other nicotinic receptors, including the α4β2, ganglionic (α3β4) and muscle subtypes. The transgenic th(tk−)/th(tk−) mouse model that reflects many of the developmental, anatomical, and multi-transmitter biochemical aspects of schizophrenia was used to assess the antipsychotic effects of TC-5619. In these mice TC-5619 acted both alone and synergistically with the antipsychotic clozapine to correct impaired pre-pulse inhibition (PPI) and social behavior which model positive and negative symptoms, respectively. Antipsychotic and cognitive effects of TC-5619 were also assessed in rats. Similar to the results in the transgenic mice, TC-5619 significantly reversed apomorphine-induced PPI deficits. In a novel object recognition paradigm in rats TC-5619 demonstrated long-lasting enhancement of memory over a wide dose range. These results suggest that alpha7-selective agonists such as TC-5619, either alone or in combination with antipsychotics, could offer a new approach to treating the constellation of symptoms associated with schizophrenia, including cognitive dysfunction.

Percutaneous coronary intervention is first-line therapy for acute coronary syndromes (ACS) but can promote cardiomyocyte death and cardiac dysfunction via reperfusion injury, a phenomenon driven in large part by oxidative stress. Therapies to limit this progression have proven elusive, with no major classes of new agents since the development of anti-platelets/anti-thrombotics. We report that cardiac troponin I–interacting kinase (TNNI3K), a cardiomyocyte-specific kinase, promotes ischemia/reperfusion injury, oxidative stress, and myocyte death. TNNI3K-mediated injury occurs through increased mitochondrial superoxide production and impaired mitochondrial function and is largely dependent on p38 mitogen-activated protein kinase (MAPK) activation. We developed a series of small-molecule TNNI3K inhibitors that reduce mitochondrial-derived superoxide generation, p38 activation, and infarct size when delivered at reperfusion to mimic clinical intervention. TNNI3K inhibition also preserves cardiac function and limits chronic adverse remodeling. Our findings demonstrate that TNNI3K modulates reperfusion injury in the ischemic heart and is a tractable therapeutic target for ACS. Pharmacologic TNNI3K inhibition would be cardiac-selective, preventing potential adverse effects of systemic kinase inhibition.