Nucleotide sequence of cDNA clones encoding the beta subunit of mitochondrial ATP synthase from the green alga Chlamydomonas reinhardtii: the precursor protein encoded by the cDNA contains both an N-terminal presequence and a C-terminal extension

• Published in: Plant molecular biology Vol. 19; no. 5; pp. 771 - 780
• Main Authors: Franzen, L.G, Falk, G
• Format: Journal Article
• Language: English
• Published: Netherlands 01.08.1992
• Subjects: adenosinetriphosphatase; Amino Acid Sequence; amino acid sequences; Animals; atpb gene; Base Sequence; Blotting, Southern; Chlamydomonas reinhardtii; Chlamydomonas reinhardtii - enzymology; Chlamydomonas reinhardtii - genetics; Cloning, Molecular; complementary DNA; ddbj/x61624; DNA; embl/x61624; genbank/xb1624; mitochondria; Mitochondria - enzymology; Mitochondria - metabolism; Molecular Sequence Data; nucleotide sequences; Protein Conformation; Protein Precursors - chemistry; Protein Precursors - genetics; Proton-Translocating ATPases - chemistry; Proton-Translocating ATPases - genetics; structural genes; zymogens
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/BF00027073

cDNA and genomic clones encoding the beta subunit of mitochondrial ATP synthase from Chlamydomonas reinhardtii have been isolated using heterologous DNA probes from the photosynthetic bacterium Rhodospirillum rubrum. The protein encoded by the cDNA is 79-83% identical to corresponding proteins from higher-plant and mammalian mitochondria, and 75% identical to the R. rubrum protein. It contains both an N-terminal presequence and a unique C-terminal extension. The presequence, which is the first mitochondrial presequence determined in C. reinhardtii, is similar in structure to mitochondrial presequences from other organisms. As chloroplast from C. reinhardtii also share features with mitochondrial presequences from other organisms (L.-G. Franzen et al., FEBS Lett 260 (1990) 165-168), this raises interesting questions about protein targeting to chloroplasts and mitochondria in C. reinhardtii. The possibility that the C-terminal extension is involved in targeting the protein to the mitochondrion is discussed. Southern blot analysis indicates that the protein is encoded by a single-copy gene.