Molecular cloning and transcript mapping of the dihydroorotate dehydrogenase dhod locus of Drosophila melanogaster

Abstract

The dhod locus encodes dihydroorotate dehydrogenase, the fourth enzymatic step of de novo pyrimidine biosynthesis. This locus was cloned previously by a chromosome walk in cytogenetic region 85A. The location of dhod within 85A DNA has been determined by mapping two rearrangement mutations to a small DNA region. A nearly full-length cDNA clone of the dhod transcript was isolated and partially sequenced, to confirm its identity. The cDNA clone was also used to map the transcribed DNA. A 1.5 kb dhod RNA is described which is most abundant in embryos and displays minor length heterogeneity in pupae and adults. The developmental expression of this transcript is discussed relative to the expression of dihydroorotate dehydrogenase activity and other genes of the pyrimidine biosynthetic pathway.

Practical Three-Component Regioselective Synthesis of Drug-Like 3-Aryl(or heteroaryl)-5,6-dihydrobenzo[h]cinnolines as Potential Non-Covalent Multi-Targeting Inhibitors To Combat Neurodegenerative Diseases

“…This enzyme catalyzes the oxidation of dihydroorotate (DHO) to orotate (ORO) by engaging the flavin mononucleotide (FMN) cofactor and has profound effects on oxidative phosphorylation (OXPHOS), the tricarboxylic acid (TCA) cycle, and the generation of adenosine triphosphate (ATP) and reactive oxygen species (ROS) . It is worth mentioning that the h DHODH structure consists of a C-terminal domain and an N-terminal helical domain in which C-terminal domain is constructed by approximately 90% of residues and forms the active site, , while the N-terminal domain contains two α-helices (αA and αB) and forms a tunnel for binding the cofactor coenzyme Q (CoQ), which has been identified as the binding site of classical h DHODH inhibitors . The CoQ-binding site shows a distinctly amphiphilic feature. , Likewise, an intensively hydrophilic region is formed by polar residues Arg136, Gln47, Tyr356, Thr360, and His56, which are located at the inner of the CoQ-binding site, while the other regions of the CoQ-binding site are covered by a series of hydrophobic residues. , In recent years, it has been determined that the h DHODH enzyme is a significant drug target in various diseases such as cancer, especially acute myeloid leukemia (AML), viral diseases, neurodegenerative diseases (NDs), and autoimmunity …”

“…126 This enzyme catalyzes the oxidation of dihydroorotate (DHO) to orotate (ORO) by engaging the flavin mononucleotide (FMN) cofactor and has profound effects on oxidative phosphorylation (OXPHOS), the tricarboxylic acid (TCA) cycle, and the generation of adenosine triphosphate (ATP) and reactive oxygen species (ROS). 127 It is worth mentioning that the hDHODH structure consists of a C-terminal domain and an N-terminal helical domain in which C-terminal domain is constructed by approximately 90% of residues and forms the active site, 128,129 while the N-terminal domain contains two αhelices (αA and αB) and forms a tunnel for binding the cofactor coenzyme Q (CoQ), which has been identified as the binding site of classical hDHODH inhibitors. 129 The CoQbinding site shows a distinctly amphiphilic feature.…”