Fig. 2
Analysis of CgbHLH001 promoter activity by 5’-deletions. A Histochemical staining of Arabidopsis seedlings overexpressing PbHLH::GUS FL (full length of the CgbHLH001 promoter). (1) seedling; (2) stem; (3) flowers and early siliques; (4) mature silique, red rectangle on the silique is corresponding to the enlarged inset of seed (right) or pseudoseptum and pericarp (left). Scale bar = 0.5 cm. B Transcriptional expression of GUS gene in different tissues of Arabidopsis overexpressing PbHLH::GUS FL. C Schematic diagram of 5’-deletions of the promoter and constructs. Different truncated fragments of the promoter were constructed into plant expression vector pCAMBIA1300. (1) pCAMBIA1300: no promoter driving GUS gene; (2) PbHLH::GUS 1148, (3) PbHLH::GUS 364, (4) PbHLH::GUS 521, (5) PbHLH::GUS 960: different truncated fragments of CgbHLH001 promoter driving GUS gene; (6) PbHLH::GUS FL: full length of the CgbHLH001 promoter driving GUS gene; (7) pCAMBIA1304: CaMV35S promoter driving GUS gene. HygR: hygromycin resistant gene; E9-ter: terminator signal of the pea rbcS-E9 gene. D GUS histochemical staining in C. glaucum seedlings transiently transformed with different truncations of the CgbHLH001 promoter. E Transcriptional expression of GUS gene in accordance with treatment in D. Different lowercase letters indicate significant differences (P < 0.05) existing among different promoter truncations. In D, E, the number order is corresponding to the constructs in C