Nucleotide sequence ofAspergillus nidulansmitochondrial genes coding for ATPase subunit 6, cytochrome oxidase subunit 3, seven unidentified proteins, four tRNAs and L-rRNA

Abstract

The complete nucleotide sequence of a 14 kb segment of A. nidulans mtDNA reveals a rather compact organization of genes transcribed from the same strand and coding for two functionally known proteins, seven unidentified polypeptides (URFs), 24 tRNAs and two rRNAs. One of the URFs is located in the intron of the L-rRNA gene and codes for a basic protein of 410 residues. The other URFs are in spacer regions and code for hydrophobic proteins. URFa is homologous to human URF4, and URFb produces a polypeptide of 48 residues resembling the human URF6L product (hydrophobic N-terminus, basic C-terminus). The ATPase subunit 6 genes from mitochondria and E. coli appear to share a common ancestor. The codon frequencies of identified genes and URFs are similar, and codons ending with G or C are rarely used. The structures of tRNAs specific for arginine, asparagine, tyrosine and histidine are deduced from gene sequences.

A cluster of six tRNA genes inDrosophilamitochondrial DNA that includes a gene for an unusual tRNAserAGY

“…yakuba, other insect, and mammalian mt-tRNAs (2,5,(11)(12)(13)(14), but is quite small compared to the variable loops of some fungal mt-tRNAs (15,16), prokaryotic and non-organelle eukaryotic tRNAs (12,13). Eleven nucleotides occur between the last nucleotide of the amino-acyl stem (nucleotide 7, numbering system shown in Fig.…”

Characterization and Comparison of Mitochondrial DNAs and rRNAs from Penicillium Urticae and P. Chrysogenum

“…The minimal distance between the two mt rRNA genes was 1.36kb for P. urticae and 1-25 kb for P . chrysogenum, whereas the distance was 3.1 kb for A. nidulans (Netzker et al, 1982).…”

Complete Sequence of the Mitochondrial DNA of the Red Alga Porphyra purpurea: Cyanobacterial Introns and Shared Ancestry of Red and Green Algae

“…Table 2 also lists the codon distribution in P. purpurea protein-coding genes, which, as in most mtDNAs, is biased toward codons ending in an A or T. No significant difference in codon usage was observed in identified protein-coding genes, conserved ORFs, unique ORFs, and intronic ORFs. Moreover, there is a GTG codon in the P. purpurea cox1 gene at exactly the same position as an ATG initiator codon in the corresponding Chondrus crispus gene, strongly suggesting that GTG serves as a start codon in mitochondrial translation in P. purpurea; use of GTG initiation codons has been inferred previously in several plant and protist mitochondrial as well as bacterial systems (e.g., Netzker et al, 1982; Kozak, 1983;Lang et al, 1997). Finally, TGA is translated in P. purpurea mitochondria as tryptophan (inferred from the presence of a tRNA with anticodon UCA and multiple protein sequence alignments).…”

“…Species (with GenBank accession numbers in parentheses) are as follows : Homo, H. sapiens (J01415;Anderson et al, 1981);Mus, M. musculus (J01420;Bibb et al, 1981); Xenopus, X. laevis (M10217; Roe et al, 1985);Strongylocentrotus, S. purpuratus (X12631;Jacobs et al, 1988);Drosophila, D. yakuba (fruitfly;X03240;Clary and Wolstenholme, 1985);Metridium, M. senile (AF000023;Beagley et al, 1998); Rhizopus, R. stolonifer (chytridiomycete fungus; Laforest et al, 1997;Saccharomyces, S. cerevisiae (ascomycete fungus;X84842, V00694, V00695, J01478;de Zamaroczy and Bernardi, 1986); Pichia, P. canadensis (Hansenula wingei) (ascomycete fungus; D31785; Sekito et al, 1995); Aspergillus, A. (Emericella) nidulans (ascomycete fungus; J01387, X15441, X06960; Netzker et al, 1982;Brown, 1993); Neurospora, N. crassa (ascomycete fungus; K01181, A28755 [protein], X01850, K00825, V00668;Collins, 1993);Podospora, P. anserina (ascomycete fungus;X55026;Cummings et al, 1990); Allomyces, A. macrogynus (chytridiomycete fungus; U41288; Paquin and Lang, 1996;Paquin et al, 1997);Acanthamoeba, A. castellanii (rhizopod;U12386;Burger et al, 1995);Malawimonas, M. jakobiformis (jakobids;G. Burger, B.F. Lang, C. O'Kelly, and M.W.…”