%0 Journal Article %1 vos_hemin_2010 %A Voß, Bjoern %A Meinecke, Linda %A Kurz, Thorsten %A Al-Babili, Salim %A Beck, Christoph F. %A Hess, Wolfgang R. %D 2010 %J Plant Physiol. %K imported myown %P pp.110.158683 %R 10.1104/pp.110.158683 %T Hemin and Mg-Protoporphyrin IX Induce Global Changes in Gene Expression in Chlamydomonas reinhardtii %U http://www.plantphysiol.org/cgi/content/abstract/pp.110.158683v1 %X Retrograde signaling is a pathway of communication from mitochondria and plastids to the nucleus in the context of cell differentiation, development and stress response. In Chlamydomonas reinhardtii, the tetrapyrroles Mg-protoporphyrin IX (MgProto) and heme are only synthesized within the chloroplast, and they have been implicated in the retrograde control of nuclear gene expression in this unicellular green alga. Feeding the two tetrapyrroles to Chlamydomonas cultures was previously shown to transiently induce five nuclear genes, three of which encode the heat shock proteins HSP70A, B, and E. In contrast, controversial results exist on the possible role of MgProto in the repression of genes for light harvesting proteins in higher plants, raising the question of how important this mode of regulation is. Here we used genome-wide transcriptional profiling to measure the global impact of these tetrapyrroles on gene regulation and the scope of the response. We identified almost 1000 genes whose expression level changed transiently but significantly. Among them were only a few genes for photosynthetic proteins but several encoding enzymes of the TCA cycle, heme-binding proteins, stress-response proteins, as well as proteins involved in protein folding and degradation. More than \textgreater50\% of the latter class of genes were also regulated by heat shock. The observed drastic fold changes at RNA level did not correlate with similar changes of protein concentrations under the tested experimental conditions. Phylogenetic profiling revealed that genes of putative endosymbiontic origin are not overrepresented among the responding genes. This and the transient nature of changes in gene expression suggest a signaling role of both tetrapyrroles as secondary messengers for adaptive responses affecting the entire cell and not only organellar proteins.

@article{vos_hemin_2010, abstract = {Retrograde signaling is a pathway of communication from mitochondria and plastids to the nucleus in the context of cell differentiation, development and stress response. In Chlamydomonas reinhardtii, the tetrapyrroles Mg-protoporphyrin IX (MgProto) and heme are only synthesized within the chloroplast, and they have been implicated in the retrograde control of nuclear gene expression in this unicellular green alga. Feeding the two tetrapyrroles to Chlamydomonas cultures was previously shown to transiently induce five nuclear genes, three of which encode the heat shock proteins HSP70A, B, and E. In contrast, controversial results exist on the possible role of MgProto in the repression of genes for light harvesting proteins in higher plants, raising the question of how important this mode of regulation is. Here we used genome-wide transcriptional profiling to measure the global impact of these tetrapyrroles on gene regulation and the scope of the response. We identified almost 1000 genes whose expression level changed transiently but significantly. Among them were only a few genes for photosynthetic proteins but several encoding enzymes of the TCA cycle, heme-binding proteins, stress-response proteins, as well as proteins involved in protein folding and degradation. More than {\textgreater}50\% of the latter class of genes were also regulated by heat shock. The observed drastic fold changes at RNA level did not correlate with similar changes of protein concentrations under the tested experimental conditions. Phylogenetic profiling revealed that genes of putative endosymbiontic origin are not overrepresented among the responding genes. This and the transient nature of changes in gene expression suggest a signaling role of both tetrapyrroles as secondary messengers for adaptive responses affecting the entire cell and not only organellar proteins.}, added-at = {2016-08-23T12:53:21.000+0200}, author = {Voß, Bjoern and Meinecke, Linda and Kurz, Thorsten and Al-Babili, Salim and Beck, Christoph F. and Hess, Wolfgang R.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/220c05eae301c20f16f86d587c6010d6a/bvoss}, doi = {10.1104/pp.110.158683}, file = {HighWire Full Text PDF:/Users/bvoss/Library/Application Support/Firefox/Profiles/a6kceokb.default/zotero/storage/SJFFH63G/Voss et al. - 2010 - Hemin and Mg-Protoporphyrin IX Induce Global Chang.pdf:application/pdf;HighWire Snapshot:/Users/bvoss/Library/Application Support/Firefox/Profiles/a6kceokb.default/zotero/storage/FIVH9TET/pp.110.html:text/html}, interhash = {a32a9958a4744120a64c29647a3aca44}, intrahash = {20c05eae301c20f16f86d587c6010d6a}, journal = {Plant Physiol.}, keywords = {imported myown}, note = 00025, pages = {pp.110.158683}, timestamp = {2022-06-03T11:32:01.000+0200}, title = {Hemin and {Mg}-{Protoporphyrin} {IX} {Induce} {Global} {Changes} in {Gene} {Expression} in {Chlamydomonas} reinhardtii}, url = {http://www.plantphysiol.org/cgi/content/abstract/pp.110.158683v1}, urldate = {2010-12-09}, year = 2010 }