Functional analysis of light-dependent regulation of chloroplast gene expression by ribonucleoproteins CP31A and CP29A

Chloroplast gene expression is characterized by extensive and complex post-transcriptional RNA processing. Although a multitude of factors has been isolated that participates in this complexity, we know next to nothing about their regulatory impact on chloroplast gene expression and thus, photosynthesis. This proposal suggests investigating selected members of a family of chloroplast RNA binding proteins called cpRNPs, because they are prime candidates for mediating light-dependent regulation of post-transcriptional gene expression. We and others have shown that cpRNPs are light-regulated proteins that bind RNAs in a light-dependent fashion. Own prior work demonstrated that the cpRNP CP31A from Arabidopsis is associated in vivo with a multitude of RNAs and is responsible for stabilizing and editing selected mRNAs. Next, we wish to concentrate our efforts on understanding how and where exactly CP31A and the related CP29A are bound on chloroplast mRNAs using a combination of ribonomics and classical in vitro techniques. In parallel, we will explore the expected redundancy of cpRNPs by generating n-tuple mutants of phylogentically and functionally related cpRNPs. Lastly, we will monitor RNA binding of CP31A and CP29A on a transcriptome-wide level in response to shifts in light-irradiation and explore how phosphorylation of these proteins impacts this light-dependent RNA association. Together, we expect that this work will expand our understanding of this exceptional family of chloroplast RNA binding proteins both on a mechanistic and regulatory level.

Principal Investigators
Schmitz-Linneweber, Christian Prof. Dr. (Details) (Genetics)

Financer
DFG: Sachbeihilfe

Duration of Project
Start date: 04/2011
End date: 03/2013

Last updated on 2020-01-06 at 17:45