Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Overexpression of the UGT73C6 alters brassinosteroid glucoside formation in Arabidopsis thaliana | Husar et al. BMC Plant Biology 2011 11 51 http 1471-2229 11 51 BMC Plant Biology RESEARCH ARTICLE Open Access Overexpression of the UGT73C6 alters brassinosteroid glucoside formation in Arabidopsis thaliana Sigrid Husar 1 Franz Berthiller2 Shozo Fujioka3 Wilfried Rozhon1 Mamoona Khan1 Florian Kalaivanan1 Luisa Elias4 KC I I I í- c I_I I z z I r 4 Vì I 14 D I V c r I I r z-xr2 D I I I Z S. I í IXr r Iz 2 I_I I I r I I c z k f z 3 c I c x I I I4 I D z t A 1 - r 4 Gillian S Higgins Yi Li Rainer SChUhmacher Rudolf Krska Hideharu Seto Fabian E Vaistij Dianna Bowles and Brigitte Poppenberger1 4 Abstract Background Brassinosteroids BRs are signaling molecules that play essential roles in the spatial regulation of plant growth and development. In contrast to other plant hormones BRs act locally close to the sites of their synthesis and thus homeostatic mechanisms must operate at the cellular level to equilibrate BR concentrations. Whilst it is recognized that levels of bioactive BRs are likely adjusted by controlling the relative rates of biosynthesis and by catabolism few factors which participate in these regulatory events have as yet been identified. Previously we have shown that the UDP-glycosyltransferase UGT73C5 of Arabidopsis thaliana catalyzes 23-O-glucosylation of BRs and that glucosylation renders BRs inactive. This study identifies the closest homologue of UGT73C5 UGT73C6 as an enzyme that is also able to glucosylate BRs in planta. Results In a candidate gene approach in which homologues of UGT73C5 were screened for their potential to induce BR deficiency when over-expressed in plants UGT73C6 was identified as an enzyme that can glucosylate the BRs CS and BL at their 23-O-positions in planta. GUS reporter analysis indicates that UGT73C6 shows over-lapping but also distinct expression patterns with UGT73C5 and YFP reporter data suggests that at the cellular level both UGTs localize to the cytoplasm and to the nucleus. A liquid chromatography
