J. Martinezgonzalez et Fg. Hegardt, CYTOCHROME-C-OXIDASE SUBUNIT-I FROM THE COCKROACH BLATTELLA-GERMANICA- CLONING, DEVELOPMENTAL PATTERN AND TISSUE EXPRESSION, Insect biochemistry and molecular biology, 24(6), 1994, pp. 619-626
The nucleotide sequence of a cDNA corresponding to the transcription p
roduct of the mitochondrial structural gene cytochrome c oxidase subun
it I was determined. A polypeptide of 508 residues was deduced from th
e reading frame established by the nucleotide sequence. TGA codes tryp
tophan, as in most other mitochondrial systems. From the comparison of
the amino acid sequence of the putative Blattella germanica cytochrom
e c oxidase with those of Drosophila, we conclude that ATA and AGA cod
ons specify methionine and serine respectively, instead of isoleucine
and arginine. The sequence proposed for cytochrome c oxidase subunit I
of B. germanica is largely homologous to that of other species. From
the alignment of cytochrome c oxidase subunit I protein sequences we h
ave found that 125 residues (positional identity of 22.3%) have remain
ed invariant in this enzyme for more than one billion years of diverge
nce. There is a developmental pattern of gene expression affecting the
embryo stages. Northern blot analysis of RNA samples from different a
dult female tissues shows high cytochrome c oxidase subunit I mRNA lev
els in gut and fat body, and lower levels in ovary and colleterial gla
nds.