This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Normal human cells have a limited capacity to proliferate, a process termed replicative aging. Increasing evidence has implicated telomeres, the structures that cap the ends of the chromosomes, as the molecular clock that counts the number of times the cell has divided. The mechanism of lagging-strand DNA synthesis prevents DNA polymerase from replicating the DNA all the way to the 5''''end of a linear chromosome, leaving a 3''''overhang and causing the chromosomes to shorten every time a cell divides. Human telomeres are composed of many kilobases of the repetitive sequence TTAGGG that, together with telomere-binding proteins, prevent the cell from recognizing the end of the chromosome as a DNA break needing repair. Cellular senescence may occur when some of the telomeres have shortened sufficiently to induce a DNA damage signal. Cancer cells escape the proliferative limits of replicative aging by up-regulating the expression of telomerase, an enzyme capable of adding telomere repeats to the ends of the chreomsomes and maintaining their length. Using methods for identifying the presence of modified nucleotides in subtelomeric DNA, for purifying telomeres (based on the presence of the 3''''G-rich overhang) that yields a greater than 1000-fold enrichment in a single step, for determining the size of the overhangs, and for measuring telomere sizes in interphase nuclei. Chromatographic separation for the telomeric nucleobases has been developed. It is a HILIC based separation appropriate for these very hydrophilic compounds and it also affords high mass spectrometric sensitivity. The method has been adapted to be used on nano-LC columns and nano electro spray ionization to increase the sensitivity

National Institute of Health (NIH)
National Center for Research Resources (NCRR)
Biotechnology Resource Grants (P41)
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Special Emphasis Panel (ZRG1-BCMB-K (40))
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Washington University
Internal Medicine/Medicine
Schools of Medicine
Saint Louis
United States
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Hölttä, Mikko; Dean, Robert A; Siemers, Eric et al. (2016) A single dose of the γ-secretase inhibitor semagacestat alters the cerebrospinal fluid peptidome in humans. Alzheimers Res Ther 8:11
Mertins, Philipp; Mani, D R; Ruggles, Kelly V et al. (2016) Proteogenomics connects somatic mutations to signalling in breast cancer. Nature 534:55-62
Karner, Courtney M; Esen, Emel; Chen, Jiakun et al. (2016) Wnt Protein Signaling Reduces Nuclear Acetyl-CoA Levels to Suppress Gene Expression during Osteoblast Differentiation. J Biol Chem 291:13028-39
Murata, Takahiro; Dietrich, Hans H; Horiuchi, Tetsuyoshi et al. (2016) Mechanisms of magnesium-induced vasodilation in cerebral penetrating arterioles. Neurosci Res 107:57-62
Sterl, Karin; Wang, Songyan; Oestricker, Lauren et al. (2016) Metabolic responses to xenin-25 are altered in humans with Roux-en-Y gastric bypass surgery. Peptides 82:76-84
Lucey, Brendan P; Mawuenyega, Kwasi G; Patterson, Bruce W et al. (2016) Associations Between β-Amyloid Kinetics and the β-Amyloid Diurnal Pattern in the Central Nervous System. JAMA Neurol :
Wang, Xiaojing; Wu, Yunkou; Soesbe, Todd C et al. (2015) A pH-Responsive MRI Agent that Can Be Activated Beyond the Tissue Magnetization Transfer Window. Angew Chem Int Ed Engl 54:8662-4
Kovacs, Erika; Das, Rahul; Wang, Qi et al. (2015) Analysis of the Role of the C-Terminal Tail in the Regulation of the Epidermal Growth Factor Receptor. Mol Cell Biol 35:3083-102
Frank, Pinar; Siebenhofer, Bernhard; Hanzer, Theresa et al. (2015) Proteo-lipobeads for the oriented encapsulation of membrane proteins. Soft Matter 11:2906-8
Thimgan, Matthew S; Seugnet, Laurent; Turk, John et al. (2015) Identification of genes associated with resilience/vulnerability to sleep deprivation and starvation in Drosophila. Sleep 38:801-14

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