Cloning and developmental expression of zebrafish GTP cyclohydrolase I

Cloning and developmental expression of zebrafish GTP cyclohydrolase I

GTP cyclohydrolase I (GCH) catalyses the conversion of GTP to dihydroneopterin triphosphate, initiating the pteridine pathway. The final product tetrahydrobiopterin (H4biopterin) is the cofactor for neurotransmitter synthesis and for tyrosine supply during melanogenesis. Sepiapterin accumulates as a pigment. We cloned the zebrafish gch cDNA, which encodes a protein highly homologous to other ve...

GTP cyclohydrolase I feedback regulatory protein is a pentamer of identical subunits. Purification, cDNA cloning, and bacterial expression.

GTP cyclohydrolase I feedback regulatory protein (GFRP) mediates feedback inhibition of GTP cyclohydrolase I activity by tetrahydrobiopterin and also mediates the stimulatory effect of phenylalanine on the enzyme activity. To characterize the molecular structure of GFRP, we have purified it from rat liver using an efficient step of affinity chromatography and isolated cDNA clones, based on part...

Structure and mechanism of GTP cyclohydrolase I of Escherichia coli.

GTP cyclohydrolases I and I1 catalyze the first committed steps in the pathways of pteridine and flavin biosynthesis [ I ] . A reaction pathway for GTP cyclohydrolase I involving the release of C8 of GTP as formate, followed by Amadori rearrangement and ring closure (see Fig. I), has been proposed earlier [2]. The enzyme was first purified and characterised by Yim and Brown [3] Recombinant GTP ...

Cloning and developmental expression of a zebrafish meis2 homeobox gene

We show here that a zebrafish meis2 gene homolog has a dynamic expression pattern in the developing mesoderm and central nervous system. Meis family homeodomain proteins are known to act as cofactors with other homeodomain proteins. We find expression of meis2.1 in the developing zebrafish hindbrain and somites, correlating with reported sites of zebrafish hox gene expression, as well as in pre...

Defect in GTP-cyclohydrolase