Analysis of pentatricopeptide repeat proteins in vivo: target RNAs and functions III

We want to define targets and functions of selected PPR proteins. The focus is on a subset of PPRs, for which null-alleles in Arabidopsis have been shown to lead to an embryo-defective phenotype. These PPRs are likely to have a very basic function for chloroplast- and thus plant-development, at least in Arabidopsis. The work rests on two general approaches:

1. Definition of PPR RNA Targets
Only for very few RNA binding proteins have target RNAs been determined directly and if so, evidence was based on in vitro studies. We are using a novel approach that couples classical immunoprecipitation techniques with microarray analysis (RIP-Chip).

2. Functional Analysis via Reverse Genetics
It is a well-established fact that chloroplast development in grass species like maize is NOT essential for plant development, quite in contrast to dicot species like Arabidopsis. Therefore, PPR mutants for genes that are essential for embryo development in Arabidopsis will be sought in a maize mutant bank made available by Alice Barkan ( Recovered mutants will be analyzed for defects in plastid RNA metabolism, guided by RIP-Chip results.

Principal Investigators
Schmitz-Linneweber, Christian Prof. Dr. (Details) (Junior Research Groups (Biology))

DFG: Nachwuchsgruppe

Duration of Project
Start date: 11/2009
End date: 09/2011

1. Tillich M, Le Sy V, Schulerowitz K, von Haeseler A, Maier U, and Schmitz-Linneweber C. Frequent Losses and a Rare Gain of Chloroplast RNA Editing Sites in Seed Plants. eingereicht; im Anhang
2. Tillich M, Hardel S, Kupsch C, Armbruster U, Delannoy E, Gualberto J, Lehwark P, Leister D, Small I, and Schmitz-Linneweber C. (2009) Chloroplast ribonucleoprotein CP31A is required for editing and stability of specific chloroplast mRNAs. Proc. Natl. Acad. Sci. USA; im Druck; im Anhang.
3. Schmitz-Linneweber C and Small I. (2008) Pentatricopeptide repeat proteins a socket set for organelle gene expression. Trends Plant Sci. invited review; 13:663-670
4. Maier U-G, Bozarth A, Funk HT, Zauner S, Rensing SA, Schmitz-Linneweber C, Börner T, and Tillich M. (2008) Complex Chloroplast RNA Metabolism: Just Debugging the Genetic Programme? BMC Biol. 6:36-40.
5. Beick S*, Schmitz-Linneweber C*, Williams-Carrier R, Jensen B, and Barkan A. (2008). The pentatricopeptide repeat protein PPR5 stabilizes a specific tRNA precursor in maize chloroplasts. *equally contributed. Mol Cell Biol; 28:5337-5347.
6. O Toole N, Hattori M, Andres C, Iida K, Lurin C, Schmitz-Linneweber C, Sugita M, and Small I. (2008). On the expansion of the pentatricopeptide repeat gene family in plants: Mol Biol Evol. 25:1120-1128.
7. Legen, J, Wanner, G, Herrmann, RG, Small, I, and Schmitz-Linneweber, C. (2007). Plastid tRNA Genes trnC-GCA and trnN-GUU are essential for plant cell development. Plant J. 51:751-762.

Last updated on 2020-13-03 at 23:06