The plastid hexokinase pHXK: a node of convergence for sugar and plastid signals in Arabidopsis.
The inhibitors to plastid gene expression (PGE) were effective in preventing nuclear photosynthetic gene expression only if applied within the first 2-3 days of Arabidopsis seedling development. However, the signal transduction processes are still unknown. In this investigation, we found 3% glucose with 1mM chloramphenicol co-treatment repressed LHCB transcript significantly in mature Arabidopsis seedlings, while effective solo glucose treatment needed a concentration of 7%. The repressive effects of glucose and chloramphenicol on LHCB expression were inhibited in phxk (plastid hexokinase) mutant. pHXK enzyme activities, location, function in signal transduction, and cross talk to plastid GUN1 protein (a key signaling factor) were also investigated. The data suggest that pHXK may be a node of convergence for sugar-mediated and PGE-derived signals in Arabidopsis.
Zhang
Zhong-Wei
ZW
Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, Sichuan University, Chengdu 610064, China.
Yuan
Shu
S
Xu
Fei
F
Yang
Hui
H
Zhang
Nian-Hui
NH
Cheng
Jian
J
Lin
Hong-Hui
HH
D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D050260:Carbohydrate Metabolism; D002701:Chloramphenicol / Q000494:pharmacology; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D017343:Genes, Plant; D005937:Glucaric Acid / Q000494:pharmacology; D006593:Hexokinase / Q000235:genetics / Q000378:metabolism*; D045342:Light-Harvesting Protein Complexes / Q000235:genetics; D008954:Models, Biological; D009154:Mutation; D010641:Phenotype; D030821:Plants, Genetically Modified; D018087:Plastids / Q000201:enzymology* / Q000235:genetics; D015398:Signal Transduction
D029681:Arabidopsis Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; C519677:GUN1 protein, Arabidopsis; D045342:Light-Harvesting Protein Complexes; D002701:Chloramphenicol; D006593:Hexokinase; D005937:Glucaric Acid