Open AccessManipulating Chloroplast Gene Expression: A Genetic and Mechanistic Analysis of Processes that Control RNA Stability
Author(s) -
David L. Stern,
Gadi Schuster
Publication year - 2004
Language(s) - English
Resource type - Reports
DOI - 10.32747/2004.7586541.bard
Subject(s) - exoribonuclease , polynucleotide phosphorylase , biology , nuclease , gene , rna , gene expression , chloroplast , degradosome , polyadenylation , genetics , microbiology and biotechnology , biochemistry , purine nucleoside phosphorylase , non coding rna , rnase p , enzyme , purine
New potential for engineering chloroplasts to express novel traits has stimulated research into relevant techniques and genetic processes, including plastid transformation and gene regulation. This BARD-funded research dealt with the mechanisms that influence chloroplast RNA accumulation, and thus gene expression. Previous work on cpRNA catabolism has elucidated a pathway initiated by endonucleolytic cleavage, followed by polyadenylation and exonucleolytic degradation. A major player in this process is the nucleus-encoded exoribo-nuclease/polymerase polynucleotide phosphorylase (PNPase). Biochemical characterization of PNPase has revealed a modular structure that controls its RNA synthesis and degradation activities, which in turn are responsive to the phosphate (P) concentration. During the funding period, new insights emerged into the molecular mechanism of RNA metabolism in the chloroplast and cyanobacteria, suggesting strategies for improving agriculturally-important plants or plants with novel introduced traits.