The structure and light-dependent transient expression of a nuclear-encoded chloroplast protein gene from pea (Pisum sativum L.)

Abstract

A nuclear gene encoding a light-induced transiently expressed protein that is localized in the chloroplast has been isolated from an EMBL3 library of pea DNA. The gene is a member of a multigene family. The sequence of the gene contains the complete reading frame of previously characterized cDNA clones and two introns in the 5′ region of the protein coding sequence. Primer extension and S1 nuclease studies have defined the cap site. Two TATA boxes are found 5′ to the initiating methionine codon. Only a limited homology is found between the presequence of this gene and transit sequences of other previously sequenced precursors. Isolated nuclei of pea have been labelled and the in vitro synthesized transcripts analysed. The results show that the light-dependent expression of the gene family is regulated at the level of transcription.