Numerous pediatric neurogenetic diseases may be optimally treated by in utero gene therapy (IUGT); but advancing such treatments requires animal models that recapitulate developmental physiology relevant to humans. One disease that could benefit from IUGT is the autosomal recessive motor neuron disease spinal muscular atrophy (SMA). Current SMA gene-targeting therapeutics are more efficacious when delivered shortly after birth, however postnatal treatment is rarely curative in severely affected patients.
View Article and Find Full Text PDFBackground: Carbohydrate restriction shows promise for diabetes, but concerns regarding high saturated fat content of low-carbohydrate diets limit widespread adoption.
Objectives: This preplanned ancillary study aimed to determine how diets varying widely in carbohydrate and saturated fat affect cardiovascular disease (CVD) risk factors during weight-loss maintenance.
Methods: After 10-14% weight loss on a run-in diet, 164 participants (70% female; BMI = 32.
Heat shock protein beta-1 (HSPB1), is a ubiquitously expressed, multifunctional protein chaperone. Mutations in HSPB1 result in the development of a late-onset, distal hereditary motor neuropathy type II (dHMN) and axonal Charcot-Marie Tooth disease with sensory involvement (CMT2F). The functional consequences of HSPB1 mutations associated with hereditary neuropathy are unknown.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
July 2016
A single bout of exhaustive exercise signals expression of vascular endothelial growth factor (VEGF) in the exercising muscle. Previous studies have reported that mice with life-long deletion of skeletal myofiber VEGF have fewer capillaries and a severe reduction in endurance exercise. However, in adult mice, VEGF gene deletion conditionally targeted to skeletal myofibers limits exercise capacity without evidence of capillary regression.
View Article and Find Full Text PDFBackground: Hif1p is an H3/H4-specific histone chaperone that associates with the nuclear form of the Hat1p/Hat2p complex (NuB4 complex) in the yeast Saccharomyces cerevisiae. While not capable of depositing histones onto DNA on its own, Hif1p can act in conjunction with a yeast cytosolic extract to assemble nucleosomes onto a relaxed circular plasmid.
Results: To identify the factor(s) that function with Hif1p to carry out chromatin assembly, multiple steps of column chromatography were carried out to fractionate the yeast cytosolic extract.
Tumors with defective mismatch repair acquire large numbers of strand slippage mutations including frameshifts in coding sequence repeats. We identified a mutational hotspot, p.T204fs, in the insulator-binding protein (CTCF) in MSI-positive endometrial cancers.
View Article and Find Full Text PDFThe protein deacetylase, sirtuin 1 (SIRT1), is a proposed master regulator of exercise-induced mitochondrial biogenesis in skeletal muscle, primarily via its ability to deacetylate and activate peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). To investigate regulation of mitochondrial biogenesis by SIRT1 in vivo, we generated mice lacking SIRT1 deacetylase activity in skeletal muscle (mKO). We hypothesized that deacetylation of PGC-1α and mitochondrial biogenesis in sedentary mice and after endurance exercise would be impaired in mKO mice.
View Article and Find Full Text PDFThe in vitro evaluation of histones and their PTMs has drawn substantial interest in the development of epigenetic therapies. The differential expression of histone isoforms may serve as a potential marker in the classification of diseases affected by chromatin abnormalities. In this study, protein profiling by LC and MS was used to explore differences in histone composition in primary chronic lymphocytic leukemia (CLL) cells.
View Article and Find Full Text PDFLong-term exposure of humans and many mammals to hypoxia leads to the activation of several cellular mechanisms within skeletal muscles that compensate for a limited availability of cellular oxygen. One of these cellular mechanisms is to increase the expression of a subset of hypoxia-inducible genes, including the expression of vascular endothelial growth factor (VEGF). The VEGF promoter contains a hypoxic response element (HRE) that can bind the transcription factor, hypoxia-inducible factor-1alpha; (HIF-1alpha), and initiate transcriptional activation of the VEGF gene.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
August 2008
The purpose of the present study was 1) to develop a stable model for measuring contraction-induced elevations in mRNA in single skeletal muscle fibers and 2) to utilize this model to investigate the response of heat shock protein 72 (HSP72) mRNA following an acute bout of fatiguing contractions. Living, intact skeletal muscle fibers were microdissected from lumbrical muscle of Xenopus laevis and either electrically stimulated for 15 min of tetanic contractions (EX; n=26) or not stimulated to contract (REST; n=14). The relative mean developed tension of EX fibers decreased to 29+/-7% of initial peak tension at the stimulation end point.
View Article and Find Full Text PDFMethods for accurately quantitating changes in histone post-translational modifications are necessary for developing an understanding of how their dynamic nature influences nuclear events involving access to genomic DNA. This article describes methods for the use of in vivo stable isotope label incorporation for quantitating the levels of modification at specific residues in histone proteins. These methods are applicable to a wide variety of model systems and examples of their use in both mammalian cells and Saccharomyces cerevisiae are presented.
View Article and Find Full Text PDFThis paper describes an integrated approach that couples stable isotope labeling with amino acids in cell culture to acetic acid-urea polyacrylamide gel electrophoresis (AU-PAGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the quantitation and dynamics of histone H4 acetylation. The 697 acute lymphoblastic cell lines were grown in regular medium and in medium in which lysine was substituted with deuterium-labeled lysine. Histone deacetylase (HDAC) activity was inhibited by addition of the HDAC inhibitor depsipeptide to the culture medium for different exposure times.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
May 2007
Here we describe the use of reverse-phase liquid chromatography mass spectrometry (RPLC-MS) to simultaneously characterize variants and post-translationally modified isoforms for each histone. The analysis of intact proteins significantly reduces the time of sample preparation and simplifies data interpretation. LC-MS analysis and peptide mass mapping have previously been applied to identify histone proteins and to characterize their post-translational modifications.
View Article and Find Full Text PDFDisrupted patterns of acetylation and deacetylation of core histones play an important role in silencing transcription of hematopoietic important genes in acute myeloid leukemia (AML). A thorough investigation of these mechanisms and the response to pharmacologic modifiers will provide a better understanding of the role of histone acetylation in leukemogenesis. We describe here an analytical approach that combines acid urea polyacrylamide gel electrophoresis (AU-PAGE), amino acid coded mass tagging (AACM), and mass spectrometry (MS) for the investigation of histone acetylation patterns.
View Article and Find Full Text PDFWomen may experience greater pulmonary gas exchange impairment during exercise than men. To test this we used the multiple inert gas elimination technique to study eight women and seven men matched for age, height and (O(2) max) ( approximately 48 ml x kg(-1) min(-1)) during normoxic and hypoxic (inspired P(O(2))= 95 Torr) cycle exercise. Resting lung function was similar between the sexes, except for a lower carbon monoxide diffusing capacity (DL(CO)) in women (P < 0.
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