Functional characterization of the Ginkgo biloba chalcone synthase gene promoter in transgenic tobacco
Functional characterization of the Ginkgo biloba chalcone synthase gene promoter in transgenic tobacco
复制标题
转基因烟草中银杏查尔酮合酶基因启动子的功能表征
DOI：
10.4238/2014.april.30.6
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发表时间：
2014-01-01
影响因子：
0.4
通讯作者：
Cao, F. L.
中科院分区：
文献类型：
--
作者：
Li, L. L.;Cheng, H.;Cao, F. L.
采用基因组步移法克隆了银杏查尔酮合成酶基因启动子调控序列（2273 bp）。克隆了GbCHS启动子5'上游翻译起始位点，命名为GbCHSP。构建了pBI 121 +CHSP：GUS和pBI 121 - 35 S：GUS两个质粒，并通过LBA 4404转化烟草。我们发现GbCHSP可以驱动GUS基因在烟草中瞬时表达，并在烟草根、茎、叶组织中差异表达。由CHSP启动子调控的GUS活性定位于根和茎生长点的组织（顶端分生组织）中。pBI 121 +CHSP：GUS基因可通过伤害、铜离子、UV-B、脱落酸和乙烯利等处理诱导表达。这种活性受到赤霉素的微弱抑制。对CHSP启动子的缺失分析表明，CHSP 1完整启动子能使GUS基因在转基因烟草中表达，并具有与35 S（CaMV）相似的活性。当存在CHSP 4、CHSP 5构建体时，GUS活性急剧下降，并且当存在CHSP 6构建体时，GUS活性几乎完全不存在。我们认为GbCHSP上游序列-1548 ~-306是CHS基因转录调控的主要区域，在G. biloba.这些结果将有助于我们了解GbCHS在G. biloba.
The regulative sequence (2273 bp) of the chalcone synthase gene promoter of biloba was cloned by genomic walking. A 2273-bp promoter 5' upstream translation start site of GbCHS was cloned and designated as GbCHSP. pBI121+CHSP: GUS and pBI121-35S:GUS were constructed and transformed into tobacco by LBA4404. We found that GbCHSP could drive transient expression of GUS in tobacco and differentially expressed in root, stem and leaf tissues of this plant. GUS activity regulated by the CHSP promoter were located in tissues (apical meristems) at the growing points of roots and stems. pBI121+CHSP: GUS could be induced by wounding, copper, UV-B, abscisic acid, and ethephon treatments of transgenic seedlings. This activity was weakly inhibited by gibberellin. Deletion analysis of the CHSP promoter in transgenic tobacco showed that CHSP1 complete promoter conferred a GUS expression and activity similar to that of 35 S(CaMV). GUS activity dropped dramatically when there were CHSP4, CHSP5 constructs and was almost totally absent when the CHSP6 construct was present. We conclude that the upstream sequence -1548 to -306 of GbCHSP is the main region for transcriptional regulation of the CHS gene and that it is activated by hormone and stress factors in G. biloba. These results will help us to understand the transcriptional regulatory mechanisms involved in GbCHS expression and flavonoid accumulation in G. biloba.