Abstract
We have isolated a 3.9-kbp-long cDNA and approximately 93 kbp long genomic DNA encoding a membrane guanylyl cyclase (designated OlGC 1) from the medaka fish Oryzias latipes, and determined their nucleotide sequences. The open reading frame for the OlGC 1 cDNA predicts a protein of 1, 055 amino acids. Phylogenetic analysis indicates OlGC 1 to be a medaka fish homolog of mammalian guanylyl cyclase B (GC-B), a member of the natriuretic peptide receptor family. Northern blot analysis demonstrated 3.9 kb OlGC 1 transcripts in the eye and brain, while reverse transcription-polymerase chain reaction (RT-PCR) analysis showed OlGC 1 transcripts in a number of adult peripheral organs as well as embryos during early stages of development. The OlGC 1 gene consists of 22 exons with an exon/intron organization similar to that of the human and rat GC-A genes, except that OlGC 1 has several very large introns. The OlGC 1 gene has no apparent TATA box or CAAT box in the region 1.2 kbp upstream of the putative transcription initiation point, but several consensus sequences for cis-regulatory elements, including an NF-IL 6-binding element, a shear stress responsive element, and multiple GM-CSF-binding elements, are present in that region.
