Genomic cloning and characterization of mitochondrial elongation factor Tu (EF-Tu) gene ( tufM) from maize ( Zea mays L.)

• Published in: Gene Vol. 257; no. 2; pp. 233 - 242
• Main Authors: Choi, Kyu Ri, Roh, Kwang-Soo, Kim, Jeong-Kook, Sim, Woong-Soep
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 31.10.2000
• Subjects: Amino Acid Sequence; Arabidopsis thaliana; Base Sequence; Blotting, Southern; Cloning, Molecular; DNA, Plant - chemistry; DNA, Plant - genetics; DNA, Plant - isolation & purification; elongation factor EF-Tu; Genes, Plant - genetics; Genomic cloning; Intron; Mitochondria - chemistry; Molecular Sequence Data; Peptide Elongation Factor Tu - genetics; Phylogeny; Primer extension; Promoter; Promoter Regions, Genetic; Sequence Alignment; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Transcription, Genetic; TufA gene; TufM gene; Zea mays; Zea mays - genetics; Promoter; EF-1α, elongation factor 1α; Intron; EF-Tu, elongation factor Tu; Primer extension; tufA, chloroplast elongation factor TuA gene; Genomic cloning; UTR, untranslated region; HMG, high mobility group; tufB, chloroplast elongation factor TuB gene; tufM, mitochondrial elongation factor Tu gene
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/S0378-1119(00)00404-2

We have cloned and characterized a mitochondrial elongation factor Tu (EF-Tu) gene ( tufM) in maize ( Zea mays L.). This maize tufM gene encoded a polypeptide of 452 amino acid residues, consisting of a putative transit peptide of 55 residues and a mature EF-Tu of 397 residues. The coding region was composed of 12 exons and 11 introns that ranged from 76 to 1673 bp in length. The deduced amino acid sequence showed 85.9% and 61.2% identity with Arabidopsis mitochondrial EF-Tu and Arabidopsis chloroplast EF-Tu sequence respectively. The transcription initiation site was determined to be 165 bp upstream of the AUG initiation codon by primer extension analysis. Southern blot analysis revealed that the cloned EF-Tu gene was encoded by the members of small gene family in maize. Although this gene does not resemble the Arabidopsis nuclear tufA gene, which encodes the plastid EF-Tu, and does not contain sequence elements found in all cyanobacterial and plastid tufA genes, the predicted amino acid sequence includes an N-terminal extension that resembles a mitochondrial targeting sequence, and shares three unique sequence elements with mitochondrial EF-Tu's from Arabidopsis thaliana, Saccharomyces cerevisiae, and Homo sapiens. Therefore, we concluded that this gene encodes the maize mitochondrial EF-Tu.