Prostate-specific membrane antigen (PSMA) is a well-characterized tumor marker associated with prostate cancer and neovasculature of most solid tumors. PSMA-specific ligands are thus being developed to deliver imaging or therapeutic agents to cancer cells. Here, we report on a crystal structure of human PSMA in complex with A9g, a 43-bp PSMA-specific RNA aptamer, that was determined to the 2.2 Å resolution limit. The analysis of the PSMA/aptamer interface allows for identification of key interactions critical for nanomolar binding affinity and high selectivity of A9g for human PSMA. Combined with in silico modeling, site-directed mutagenesis, inhibition experiments and cell-based assays, the structure also provides an insight into structural changes of the aptamer and PSMA upon complex formation, mechanistic explanation for inhibition of the PSMA enzymatic activity by A9g as well as its ligand-selective competition with small molecules targeting the internal pocket of the enzyme. Additionally, comparison with published protein-RNA aptamer structures pointed toward more general features governing protein-aptamer interactions. Finally, our findings can be exploited for the structure-assisted design of future A9g-based derivatives with improved binding and stability characteristics.

• MeSH
• antigeny povrchové chemie   MeSH
• aptamery nukleotidové chemie   MeSH
• buňky PC-3 MeSH
• glutamátkarboxypeptidasa II chemie   MeSH
• HEK293 buňky MeSH
• interakční proteinové domény a motivy MeSH
• lidé MeSH
• ligandy MeSH
• molekulární struktura MeSH
• nádorové biomarkery chemie   MeSH
• nádory prostaty metabolismus   MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

BACKGROUND: The Angiotensin-I converting enzyme (ACE) is one of the most important components of the renin-angiotensin-aldosterone system controlling blood pressure and renal functions. Inhibitors of ACE are first line therapeutics used in the treatment of hypertension and related cardiovascular diseases. Somatic ACE consists of two homologous catalytic domains, the C- and N-domains. Recent findings have shown that although both domains are highly homologous in structure, they may have different physiological functions. The C-domain is primarily involved in the control of blood pressure, in contrast to the N-domain that is engaged in the regulation of hematopoietic stem cell proliferation. The currently available ACE inhibitors have some adverse effects that can be attributed to the non-selective inhibition of both domains. In addition, specific Ndomain inhibitors have emerged as potential antifibrotic drugs. Therefore, ACE is still an important drug target for the development of novel domain-selective drugs not only for the cardiovascular system but also for other systems. OBJECTIVE: Detailed structural information about interactions in the protein-ligand complex is crucial for rational drug design. This review highlights the structural information available from crystallographic data which is essential for the development of domain selective inhibitors of ACE. METHODS: Over eighty crystal complexes of ACE are placed into the Protein Database. An overview of X-ray ACE complexes with various inhibitors in C- and N-domains and an analysis of their binding mode have given mechanistic explanation of the structural determinants of selective ligand binding. In addition, ACE domain selective inhibitors with dual modes of action in complexes with ACE are also discussed. CONCLUSION: Selectivity of ACE inhibitors for the N- and C-domain is controlled by subtle differences in the amino-acids forming the active site. Reported studies of crystal complexes of inhibitors in the C- and N-domains revealed that most selective inhibitors interact with non-conserved amino-acids between domains and have distinct interactions with the residues in the S2 and S2' subsites of the ACE catalytic site. Moreover, unusual binding of the second molecule of inhibitors in the binding cavity opens new possibilities of exploiting more distant regions of the catalytic center in structure-based design of novel drugs.

• MeSH
• angiotensin konvertující enzym chemie   metabolismus   MeSH
• inhibitory ACE chemie   metabolismus   MeSH
• katalytická doména MeSH
• krystalografie rentgenová MeSH
• lidé MeSH
• proteinové domény MeSH
• racionální návrh léčiv MeSH
• substrátová specifita MeSH
• vazba proteinů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

PURPOSE OF REVIEW: This review will discuss aspects of cytokine networks in neuroinflammatory diseases and attempt to provide some explanation for our failures and successes in translating preclinical data to benefit patients with multiple sclerosis (MS). We will discuss innate cytokines such as tumor necrosis factor alpha and interferon (IFN) beta and will then go on to cover recent findings on the role of interleukin-23 and the so-called T(H)17 cells and how they are implicated in the pathogenesis of neuroinflammation. RECENT FINDINGS: Even though IFN-beta has been used for the treatment of MS for many years, it is only recently that the mechanistic underpinnings of the IFN-beta-mediated immune modulation was discovered in preclinical models. The timeline is at odds with the idea that preclinical data should shape the design of therapeutic strategies in the clinic. Conversely, the discovery of the so-called T(H)17 cells and their association with neuroinflammation has broken the dogma that IFN-gamma-producing T(H)1 cells have the exclusive capacity to invade and destroy the central nervous system tissue. So why then did a clinical trial targeting the T(H)17-promoting cytokine interleukin-23 fail? SUMMARY: Preclinical studies using the animal models for MS have yielded promising results, but unfortunately the translation into the clinic is often disappointing. The reason for this may be the complex nature of the pathogenesis of autoimmune neuroinflammation, but more often an oversimplified interpretation of preclinical observations appears to hinder our progress.

• MeSH
• biomedicínský výzkum metody   trendy   MeSH
• cytokiny genetika   metabolismus   MeSH
• demyelinizační autoimunitní nemoci CNS imunologie   patofyziologie   patologie   MeSH
• financování organizované MeSH
• imunologické faktory farmakologie   terapeutické užití   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• preklinické hodnocení léčiv metody   trendy   MeSH
• roztroušená skleróza imunologie   patofyziologie   patologie   MeSH
• T-lymfocyty pomocné-indukující imunologie   účinky léků   MeSH
• zánět imunologie   patofyziologie   patologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• přehledy MeSH

• MeSH
• chorobopisy - počítačové systémy MeSH
• management znalostí MeSH
• metody pro podporu rozhodování MeSH
• počítačové zpracování obrazu MeSH
• počítačové zpracování signálu MeSH
• řízení zdravotnictví MeSH
• studium lékařství MeSH
• zdravotnické informační systémy MeSH
• Publikační typ
• sborníky MeSH

• Konspekt
• Lékařské vědy. Lékařství
• NLK Obory
• lékařská informatika
• NLK Publikační typ
• ročenky