ABSTRACT
Two mammalian monoamine oxidases (MAO), MAO-A and MAO-B, are similar in primary structures but have unique substrate/inhibitor selectivities. Carp (Cyprinus carpio) contains a MAO enzyme (C-MAO) with properties different from MAO-A and MAO-B. To determine the molecular characteristics of C-MAO and its phylogenetic relationship with other fish and mammalian MAOs, the primary structure of C-MAO was estimated. The putative C-MAO cDNA encodes 526 amino acids with 59.001 Da, and the deduced amino acid sequence showed as much as 68.9% homology with some mammalian MAO-A proteins, 69.8% homology with some mammalian MAO-B proteins, and as much as 92.4% homology with some fish MAOs. Comparison of two regions in the polypeptide sequence of C-MAO determining possible substrate/inhibitor preferences of MAO-A and MAO-B showed both 79.5% homologies.
Subject(s)
Carps , Monoamine Oxidase/genetics , Monoamine Oxidase/metabolism , Amino Acid Sequence , Animals , Base Sequence , Binding Sites , Carps/genetics , Cell Membrane/metabolism , Cloning, Molecular , Conserved Sequence , DNA, Complementary/genetics , Evolution, Molecular , Flavin-Adenine Dinucleotide/metabolism , Humans , Molecular Sequence Data , Monoamine Oxidase/chemistry , Monoamine Oxidase Inhibitors/pharmacology , Structure-Activity Relationship , Substrate SpecificityABSTRACT
A system has been developed to improve the efficiency of maintenance work while decreasing the radiation exposure of maintenance personnel in nuclear power plants. The input data for dose rate calculation are automatically generated by using computer-aided design data. Changes for the input data corresponding to the progress of maintenance work, such as installation of a radiation shield and removal of a component, are easily input interactively on a graphical user interface (GUI). A new method was proposed which searches the sets of source and detector points between which gamma-ray attenuation is changed by the component movement. The calculation is performed only for the changed sets, so that the change of the three-dimensional dose rate distribution is calculated rapidly according to the work progress. The dose rate distribution and the radiation exposure of maintenance personnel are displayed three-dimensionally in colour with plant components and pipes on the GUI.
Subject(s)
Maintenance/methods , Occupational Exposure/analysis , Power Plants , Radiation Monitoring/methods , Radiation Protection/methods , Software , User-Computer Interface , Body Burden , Computer Graphics , Radiation Dosage , Relative Biological EffectivenessABSTRACT
To study the molecular structure of guinea pig monoamine oxidase (MAO) and its phylogenetic relationship with other mammalian MAOs, we determined nucleotide sequences of putative MAO cDNAs isolated from guinea pig tissues. Both the 5'- and 3'-ends of the cDNAs were amplified using the RACE (rapid amplification of cDNA ends) method. The sequence (1924 bp) of a putative guinea-pig MAO-B cDNA covers a complete coding region that corresponds to 521 amino acids. We also analyzed a partial sequence of a putative guinea-pig MAO-A cDNA, which corresponds to 506 amino acids, but have left the region of 66 bp at the 3'-end undetermined. The nucleotide and deduced amino-acid sequences of the putative guinea-pig MAO cDNAs showed the highest homology with that of human MAO cDNAs among the known mammalian MAO sequences. These results suggest that guinea-pig MAOs are structurally similar to human MAOs. Our molecular phylogenetic data support the idea that guinea pigs and rodents diverged before the separation between rodents and other lineage leading to Primates and Artiodactyla.
