Sugar acts as a regulatory signal on the wound-inducible expression of SbHRGP3::GUS in transgenic plants.
SbHRGP3 encodes an HRGP whose expression is correlated with the cessation of root elongation in soybean. The wound-inducible expression of SbHRGP3 interestingly requires sucrose although wounding alone induces the expression of many HRGP genes. To examine whether sugar serves as a specific signal on the wound-inducible expression or whether sugar is required to provide ATP, we examined SbHRGP3:: GUS expression in transgenic tobacco plants. Various oligosaccharides including non-metabolizable sugar induced SbHRGP3:: GUS expression in transgenic plants. The inhibitors of photosynthesis and of cellular respiration did not affect the wound-inducible expression of SbHRGP3:: GUS. However, the induction was significantly affected by PCMBS, an inhibitor of active apoplastic phloem loading of sucrose, suggesting that SbHRGP3:: GUS expression in phloem tissues requires translocated sucrose. We therefore propose that sugar acts as a specific regulatory signal on the wound-inducible expression of SbHRGP3, rather than acting as a simple provider of ATP.
Ahn
J H
JH
School of Life Sciences and Biotechnology, Korea University, 136-701 Seoul, Korea. jahn@korea.ac.kr
Lee
J S
JS
D002241:Carbohydrates / Q000494:pharmacology*; D005966:Glucuronidase / Q000235:genetics; D010788:Photosynthesis; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000382:microbiology / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics; D013025:Glycine max / Q000235:genetics* / Q000382:microbiology / Q000502:physiology; D013050:Spectrometry, Fluorescence
D002241:Carbohydrates; D010940:Plant Proteins; D012333:RNA, Messenger; D005966:Glucuronidase