Structures of the genes for the beta and epsilon subunits of spinach chloroplast ATPase indicate a dicistronic mRNA and an overlapping translation stop/start signal.
A 2,4-kilobase-pair region of spinach chloroplast DNA adjacent to the gene for the large subunit of ribulosebisphosphate carboxylase has been analyzed by RNA hybridization, in vitro transcription/translation, and DNA sequence determination. The analysis indicates that this region carries the genes for the beta and epsilon subunits of chloroplast ATPase and that the two genes are cotranscribed into a dicistronic mRNA with 4-base-pair overlap between the stop codon of the beta-subunit gene and the start codon of the epsilon-subunit gene. The ATPase and carboxylase genes are transcribed divergently with respect to each other. The deduced amino acid sequences of the beta and epsilon subunits from spinach show 67% and 26% homology, respectively, with the published sequences of the beta and epsilon subunits of Escherichia coli ATPase.
Division of Plant Industry, Commonwealth Scientific and Industrial Research Organisation, Post Office Box 1600, Canberra City, A.C.T. 2601, Australia.
G
G
Zurawski
W
W
Bottomley
P R
PR
Whitfeld