The gene encoding the bovine guanylate cyclase isoform E (GC-E) was is
olated as a single 18 kb genomic clone and shown to have 20 exons and
19 introns. Comparison of the structure of the GC-E gene with structur
es of other membrane guanylate cyclase genes indicates that the GC-E i
s most closely related to the subfamily of sensory guanylate cyclases.
Comparison of the GC-E structure with that of the more distantly rela
ted guanylate cyclase isoform A (GCA) gene shows the most divergence i
n the extracellular and C-terminal regions, but general conservation o
f introns and exons in the intracellular kinase-like and catalytic dom
ains. RT-PCR from several bovine tissues shows that GC-E is expressed
only in the retina. Consistent with this pattern of expression, elemen
ts for the retinal-specific transcription factors RET-1, RET-2 and T a
lpha-1 are located in the 5' flanking promoter region. (C) 1997 Elsevi
er Science B.V.