cis-Regulatory elements for mesophyll-specific gene expression in the C4 plant Flaveria trinervia, the promoter of the C4 phosphoenolpyruvate carboxylase gene.
C(4) photosynthesis depends on the strict compartmentalization of CO(2) assimilatory enzymes. cis-regulatory mechanisms are described that ensure mesophyll-specific expression of the gene encoding the C(4) isoform of phosphoenolpyruvate carboxylase (ppcA1) of the C(4) dicot Flaveria trinervia. To elucidate and understand the anatomy of the C(4) ppcA1 promoter, detailed promoter/reporter gene studies were performed in the closely related C(4) species F. bidentis, revealing that the C(4) promoter contains two regions, a proximal segment up to -570 and a distal part from -1566 to -2141, which are necessary but also sufficient for high mesophyll-specific expression of the beta-glucuronidase reporter gene. The distal region behaves as an enhancer-like expression module that can direct mesophyll-specific expression when inserted into the ppcA1 promoter of the C(3) plant F. pringlei. Mesophyll expression determinants were restricted to a 41-bp segment, referred to as mesophyll expression module 1 (Mem1). Evolutionary and functional studies identified the tetranucleotide sequence CACT as a key component of Mem1.
Gowik
Udo
U
Heinrich-Heine-Universität, Institut für Entwicklungs und Molekularbiologie der Pflanzen, 40225 Düsseldorf, Germany.
Burscheidt
Janet
J
Akyildiz
Meryem
M
Schlue
Ute
U
Koczor
Maria
M
Streubel
Monika
M
Westhoff
Peter
P
D037142:Flaveria / Q000201:enzymology / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D010730:Phosphoenolpyruvate Carboxylase / Q000235:genetics*; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D017384:Sequence Deletion
D010730:Phosphoenolpyruvate Carboxylase