dc.contributor.author | Müller, Renate | |
dc.contributor.author | Nilsson, Lena | |
dc.contributor.author | Nielsen, Linda Kærgaard | |
dc.contributor.author | Nielsen, Tom Hamborg | |
dc.date.accessioned | 2013-06-17T13:36:12Z | |
dc.date.available | 2013-06-17T13:36:12Z | |
dc.date.issued | 2005 | |
dc.identifier.citation | Müller, R., Nilsson, L., Nielsen, L. K. and Hamborg Nielsen, T. (2005), Interaction between phosphate starvation signalling and hexokinase-independent sugar sensing in Arabidopsis leaves. Physiologia Plantarum, 124: 81–90 | en |
dc.identifier.uri | http://onlinelibrary.wiley.com/doi/10.1111/j.1399-3054.2005.00496.x/abstract?deniedAccessCustomisedMessage=&userIsAuthenticated=false | |
dc.identifier.uri | http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/35027 | |
dc.description.abstract | Expression of selected genes in relation to phosphate (Pi) starvation and sugar sensing was studied in leaves of Arabidopsis. Excised leaf segments with different P status were supplied with combinations of Pi and sugars. Sugar-inducible genes, encoding β-amylase (β-AMY) and chalcone synthase (CHS), were also induced by P deficiency, and were more strongly regulated by sugars when leaf segments originated from P-starved plants. Furthermore, transcript levels of the P-starvation-inducible genes ACP5 (encoding an acid phosphatase), RNS1 (encoding a ribonuclease), and IPS1 (unknown function) increased in response to exogenously applied sugars. Supply of Pi to the leaf segments reversed both P-starvation-induced and sugar-induced gene expression. These interactions reveal a close relationship between P and sugar sensing. To differentiate between hexokinase-dependent and hexokinase-independent sugar sensing the effect of the glucose analogue 2-deoxyglucose and gene expression in the hexokinase-1 deficient mutant, gin2-1, were studied. Both β-AMY and CHS were induced by supplying sucrose to excised leaves but not by 2-deoxyglucose, confirming that these genes are regulated by hexokinase-independent sugar sensing. In the gin2-1 mutant both β-AMY and CHS responded clearly to P starvation excluding that hexokinase-1 mediates the response to P. Similarly, the P-responding genes, IPS1 and RNS1 were repressed by addition of Pi also in the gin2-1 mutant. In conclusion, several phosphate starvation-induced genes are also sugar-induced and hexokinase-independent sugar sensing in Arabidopsis is strongly intensified by phosphate starvation. | en |
dc.language.iso | en | en |
dc.title | Interaction between phosphate starvation signalling and hexokinase‐independent sugar sensing in Arabidopsis leaves | en |
dc.type | Article | en |