title: Characterization of the nuclear gene encoding mitochondrial aconitase in the marine red alga Gracilaria verrucosa.
abstract: We have cloned a nuclear gene from the marine red alga Gracilaria verrucosa that encodes the complete 779 amino-acid mitochondrial aconitase (m-ACN), the first characterized from a photosynthetic organism. The N-terminal 28 deduced amino acids are predicted to constitute the mitochondrial transit peptide, the first described from a red alga. Putative transcriptional cis-acting elements were identified in the upstream untranslated region. The G. verrucosa m-ACN gene (m-ACN) is present in a single copy and is located ca. 1.5 kb upstream from the single-copy polyubiquitin gene. The single spliceosomal intron is located near the 5' end of the region encoding the mature m-ACN in precisely the same location and phase as intron 2 in Caenorhabditis elegans m-ACN; sequences at its 3' and 5' splice junctions and at the predicted lariat branch point conform well to the eukaryote consensus sequences. Multiple protein-sequence alignment of m-ACN, bacterial aconitase (b-ACN) and iron-responsive element-binding protein (IRE-BP), and phylogenetic analyses, revealed that m-ACN does not share a recent common ancestry with either b-ACN or IRE-BP.
authors.affiliation: Institute for Marine Biosciences, National Research Council of Canada, Halifax, Nova Scotia.
authors.forename: Y H
authors.initials: YH
authors.lastname: Zhou
authors.forename: M A
authors.initials: MA
authors.lastname: Ragan
mesh_terms: D000154:Aconitate Hydratase / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D002451:Cell Compartmentation / Q000235:genetics*; D002467:Cell Nucleus / Q000235:genetics*; D018628:Gene Dosage; D015698:Genomic Library; D007438:Introns / Q000235:genetics; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D021382:Protein Sorting Signals / Q000235:genetics; D017433:Protein Structure, Secondary; D012326:RNA Splicing; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics; D015183:Restriction Mapping; D000461:Rhodophyta / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D014158:Transcription, Genetic
chemical_list: D021382:Protein Sorting Signals; D000154:Aconitate Hydratase