A gene cluster in the spinach and pea chloroplast genomes encoding one CF 1 and three CF 0 subunits of the H +-ATP synthase complex and the ribosomal protein S2

Abstract

The regions of the spinach and pea chloroplast genomes containing the ATP synthase genes atpA, atpF and atpH have been sequenced. The encoded proteins, CF 1α, CF 0I and CF 0III, are well conserved between spinach and pea, and analogous to the α, b and c subunits of the Escherichia coli ATP synthase complex. The atpF gene is split by a single intron, and the exon/intron boundaries have been defined by isolating and sequencing a partial cDNA clone. Two other genes, designated atpI and rps2, located upstream from atpH, have also been sequenced. They encode a 27,000 M r hydrophobic protein analogous to the F 0a subunit of E. coli ATP synthase and a basic protein analogous to the S2 protein of the E. coli 30 S ribosomal subunit. Transcriptional analysis by electron microscopy of RNA-DNA hybrids, Northern blotting and primer extension experiments shows that these genes are transcribed and processed into a complex set of transcripts, with 5′ ends mapping upstream from the rps2, atpI and atpH genes.