Chloroplast gene expression

Group leader : Kamel HAMMANI

Research area

The chloroplast has a pivotal role in the regulation of plant cell homeostasis as it senses light via its photosynthetic apparatus and produces many metabolites that are essential for the cell. Chloroplast biogenesis and function rely on the coordinated expression of both, the chloroplast genome with endosymbiotic origin and the nuclear genome. The regulation of the expression of the chloroplast genome is particularly important for the plant acclimation to environmental and developmental changes. In chloroplasts, gene expression at the posttranscriptional level is particularly complex and requires the participation of many nuclear-encoded RNA binding proteins that virtually control any RNA-related step in chloroplast gene expression. However, only a small fraction of these RNA binding proteins have been identified and functionally characterized.

Our research team combines reverse genetics in Arabidopsis and maize with the biochemistry of RNA/protein complexes to identify these proteins and elucidate their molecular function. In addition, we aim at understanding how these nuclear-encoded RNA binding proteins contribute to the chloroplast genetic acclimation to their environment by identifying signal transducing pathways that regulate their intrinsic activity, in vivo.

Members

Selected publications

  • MATHIEU S., FOURNEL M. and HAMMANI K.

    The N- and C-terminal Domains of Artificial Pentatricopeptide Repeat Proteins are dispensable for the in vivo Stabilization of Chloroplast RNAs

    Plant and Cell Physiology, pcag010, 2026. | DOI : https://doi-org.insb.bib.cnrs.fr/10.1093/pcp/pcag010DOI logo

  • MATHIEU S., LESCH E., GARCIA S., GRAINDORGE S., SCHALLENBERG-RUDINGER M. and HAMMANI K.

    De novo RNA base editing in plant organelles with engineered synthetic P-type PPR editing factors

    Nucleic Acids Research, 53:10297-10312, 2025. | DOI : 10.1093/nar/gkaf279DOI logo

  • MÉTEIGNIER L.V., GHANDOUR R., ZIMMERMANN A., KUHN L., MEURER J., ZOSCHKE R. and HAMMANI K.

    Arabidopsis mTERF9 protein promotes chloroplast ribosomal assembly and translation by establishing ribonucleoprotein interactions in vivo

    Nucleic Acids Research, 49:1114–1132, 2021. | DOI : 10.1093/nar/gkaa1244DOI logo

  • MANAVSKI N., MATHIEU S., ROJAS M., MÉTEIGNIER L.V., BRACHMANN A., BARKAN A. and HAMMANI K.

    In vivo stabilization of endogenous chloroplast RNAs by customized artificial pentatricopeptide repeat proteins

    Nucleic Acid Research, 49:5985–5997, 2021. | DOI : 10.1093/nar/gkab390DOI logo

  • MÉTEIGNIER L.V., GHANDOUR R., MEIERHOFF K., ZIMMERMANN A., CHICHER J., BAUMBERGER N., ALIOUA A., MEURER J., ZOSCHKE R. and HAMMANI K.

    The Arabidopsis mTERF-repeat MDA1 protein plays a dual function in transcription and stabilization of specific chloroplast transcripts within the psbE and ndhH operons

    New Phytologist, 227(5):1376–1391, 2020. | DOI : 10.1111/nph.16625DOI logo