Functional Significance Of Cells Research Articles

Uncoupling histone modification crosstalk by engineering lysine demethylase LSD1.

Biochemical crosstalk between two or more histone modifications is often observed in epigenetic enzyme regulation, but its functional significance in cells has been difficult to discern. Previous enzymatic studies revealed that Lys14 acetylation of histone H3 can inhibit Lys4 demethylation by lysine-specific demethylase 1 (LSD1). In the present study, we engineered a mutant form of LSD1, Y391K, which renders the nucleosome demethylase activity of LSD1 insensitive to Lys14 acetylation. K562 cells with the Y391K LSD1 CRISPR knockin show decreased expression of a set of genes associated with cellular adhesion and myeloid leukocyte activation. Chromatin profiling revealed that the cis-regulatory regions of these silenced genes display a higher level of H3 Lys14 acetylation, and edited K562 cells show diminished H3 mono-methyl Lys4 near these silenced genes, consistent with a role for enhanced LSD1 demethylase activity. These findings illuminate the functional consequences of disconnecting histone modification crosstalk for a key epigenetic enzyme.

Proton Pumping and Non-Pumping Terminal Respiratory Oxidases: Active Sites Intermediates of These Molecular Machines and Their Derivatives.

Terminal respiratory oxidases are highly efficient molecular machines. These most important bioenergetic membrane enzymes transform the energy of chemical bonds released during the transfer of electrons along the respiratory chains of eukaryotes and prokaryotes from cytochromes or quinols to molecular oxygen into a transmembrane proton gradient. They participate in regulatory cascades and physiological anti-stress reactions in multicellular organisms. They also allow microorganisms to adapt to low-oxygen conditions, survive in chemically aggressive environments and acquire antibiotic resistance. To date, three-dimensional structures with atomic resolution of members of all major groups of terminal respiratory oxidases, heme-copper oxidases, and bd-type cytochromes, have been obtained. These groups of enzymes have different origins and a wide range of functional significance in cells. At the same time, all of them are united by a catalytic reaction of four-electron reduction in oxygen into water which proceeds without the formation and release of potentially dangerous ROS from active sites. The review analyzes recent structural and functional studies of oxygen reduction intermediates in the active sites of terminal respiratory oxidases, the features of catalytic cycles, and the properties of the active sites of these enzymes.

Eukaryotic RNA 5'-End NAD+ Capping and DeNADding.

A hallmark of eukaryotic mRNAs has long been the 5'-end m7G cap. This paradigm was recently amended by recent reports that Saccharomyces cerevisiae and mammalian cells also contain mRNAs carrying a novel nicotinamide adenine dinucleotide (NAD+) cap at their 5'-end. The presence of an NAD+ cap on mRNA uncovers a previously unknown mechanism for controlling gene expression through nucleotide metabolite-directed mRNA turnover. In contrast to the m7G cap that stabilizes mRNA, the NAD+ cap targets RNA for rapid decay in mammalian cells through the DXO non-canonical decapping enzyme which removes intact NAD+ from RNA in a process termed 'deNADding'. This review highlights the identification of NAD+ caps, their mode of addition, and their functional significance in cells.

Metaphase chromosome anomaly: association with drug resistance and cell-specific products.

Large, homogeneously staining chromosome regions which lack the longitudinal differentiation ordinarily revealed by cytogenetic "banding" methods have been found in antifolate-resistant Chinese hamster cells and also in human neuroblastoma cells established in vitro. The drug-resistant cells are characterized by excessive production of the target enzyme, dihydrofolate reducatase, while the human neuroblastoma cells have phenotypes of normal neuronal cells. The homogeneously staining region appears to represent a novel metaphase chromosome anaomaly which may have functional significance in cells with specialized properties.

A Textbook of Histology: Functional Significance of Cells and Intercellular Substances

Medical Journal of AustraliaVolume 1, Issue 6 p. 213-214 Review A Textbook of Histology: Functional Significance of Cells and Intercellular Substances First published: 01 February 1961 https://doi.org/10.5694/j.1326-5377.1961.tb82400.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume1, Issue6February 1961Pages 213-214 RelatedInformation

A Textbook of Histology. Functional Significance of Cells and Intercellular Substances. E. V. Cowdry

Previous articleNext article No AccessNew Biological BooksA Textbook of Histology. Functional Significance of Cells and Intercellular Substances. E. V. Cowdry Mary E. RawlesMary E. Rawles Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 27, Number 2Jun., 1952 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/398939 PDF download Crossref reports no articles citing this article.

A Textbook of Histology. Functional Significance of Cells and Intercellular Substances. E. V. Cowdry

<i>A Textbook of Histology. Functional Significance of Cells and Intercellular Substances</i>. E. V. Cowdry

A Textbook of Histology: The Functional Significance of Cells and Intercellular Substances

Journal Article A Textbook of Histology: The Functional Significance of Cells and Intercellular Substances Get access A Textbook of Histology: The Functional Significance of Cells and Intercellular Substances. By E. V. Cowdry, Professor of Anatomy, The School of Medicine, Washington University, and Director of Research, The Barnard Free Skin and Cancer Hospital, St. Louis, Mo. Third Edition. Cloth. Price, $7. Pp. 427, with 317 illustrations. Philadelphia: Lea & Febiger, 1944. Physical Therapy, Volume 25, Issue 2, March 1945, Page 103, https://doi.org/10.1093/ptj/25.2.103a Published: 01 March 1945

A Textbook of Histology: Functional Significance of Cells and Intercellular Substances

Journal Article A Textbook of Histology: Functional Significance of Cells and Intercellular Substances Get access A Textbook of Histology: Functional Significance of Cells and Intercellular Substances. By E. V. Cowdry, Professor of Cytology in the School of Medicine, Washington University, St. Louis, Missouri. Second Edition. Cloth. Price, $7.00. Pp. 600, with 323 illustrations. Philadelphia: Lea & Febiger, 1938. Physical Therapy, Volume 19, Issue 2, March 1939, Page 109, https://doi.org/10.1093/ptj/19.2.109b Published: 01 March 1939

A textbook of histoilogy. Functional significance of cells and intercellular substances. E. V. Cowdry. 503 pp. Lea and Febiger, Philadelphia, Pa.

A textbook of histoilogy. Functional significance of cells and intercellular substances. E. V. Cowdry. 503 pp. Lea and Febiger, Philadelphia, Pa.

A Textbook of Histology: Functional Significance of Cells and Intercellular Substances

A Textbook of Histology: Functional Significance of Cells and Intercellular Substances

A Textbook of Histology: Functional Significance of Cells and Intercellular Substances.

A Textbook of Histology: Functional Significance of Cells and Intercellular Substances.

A Textbook of Histology: The Functional Significance of Cells and Intercellular Substances

A Textbook of Histology: The Functional Significance of Cells and Intercellular Substances