Characterization of recombinant human nicotinamide mononucleotide adenylyl transferase (NMNAT), a nuclear enzyme essential for NAD synthesis
| Autor: | Christoph Weise, Monica Hirsch-Kauffmann, Felicitas Lerner, Mathias Ziegler, Thomas Specht, Shiao Li Oei, Klaus Hennig, Manfred Schweiger, Marc Niere |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
DNA
Complementary Molecular Sequence Data Biophysics Poly(ADP-ribose) Polymerase Inhibitors Transfection Biochemistry law.invention Sequence Analysis Protein Structural Biology law NMNAT1 Nicotinamide mononucleotide adenylyl transferase Tumor Cells Cultured Genetics Humans Amino Acid Sequence Nicotinamide-Nucleotide Adenylyltransferase Phosphorylation NAD synthesis Molecular Biology Polymerase Nicotinamide mononucleotide Cell Nucleus chemistry.chemical_classification Base Sequence biology Nicotinamide-nucleotide adenylyltransferase NMNAT Protein primary structure Cell Biology NAD Recombinant Proteins Enzyme chemistry biology.protein Recombinant DNA Nuclear localization sequence |
| Zdroj: | FEBS Letters. 492:95-100 |
| ISSN: | 0014-5793 |
| DOI: | 10.1016/s0014-5793(01)02180-9 |
| Popis: | Nicotinamide mononucleotide adenylyl transferase (NMNAT) is an essential enzyme in all organisms, because it catalyzes a key step of NAD synthesis. However, little is known about the structure and regulation of this enzyme. In this study we established the primary structure of human NMNAT. The human sequence represents the first report of the primary structure of this enzyme for an organism higher than yeast. The enzyme was purified from human placenta and internal peptide sequences determined. Analysis of human DNA sequence data then permitted the cloning of a cDNA encoding this enzyme. Recombinant NMNAT exhibited catalytic properties similar to the originally purified enzyme. Human NMNAT (molecular weight 31 932) consists of 279 amino acids and exhibits substantial structural differences to the enzymes from lower organisms. A putative nuclear localization signal was confirmed by immunofluorescence studies. NMNAT strongly inhibited recombinant human poly(ADP-ribose) polymerase 1, however, NMNAT was not modified by poly(ADP-ribose). NMNAT appears to be a substrate of nuclear kinases and contains at least three potential phosphorylation sites. Endogenous and recombinant NMNAT were phosphorylated in nuclear extracts in the presence of [γ- 32 P]ATP. We propose that NMNAT’s activity or interaction with nuclear proteins are likely to be modulated by phosphorylation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text