Cloning and functional characterization of epidermis-specific promoter MtML1 from Medicago truncatula

Publication date: Available online 11 May 2019Source: Journal of BiotechnologyAuthor(s): Li Gao, Tian Ye, Meng-Ci Chen, Wei Li, Tian-Ge Gao, Hong-Ju Yin, Jin-Lin Zhang, Tanweer Kumar, Lin-Bo Liu, Suo-Min WangAbstractEpidermis-specific promoters are necessary for ectopic expression of specific functional genes such as the cuticle-related genes. Previous studies indicated that both ECERIFERUM 6 (AtCER6) and ARABIDOPSIS THALIANA MERISTEM L1 LAYER (ATML1) promoters from Arabidopsis thaliana can drive gene expression specifically in the epidermis of shoot apical meristems (SAMs) and leaves. However, the epidermis-specific promoters from legume plants have not been reported. Here, we cloned a 5′ flanking sequence from the upstream -2150 bp to the translational start ATG codon of MtML1 gene of legume model plant Medicago truncatula. PlantCARE analysis indicated that this sequence matches the characteristics of a promoter, having TATA box and CAAT box, as well as contains some conserved elements of epidermis-specific promoters like AtCER6 and ATML1 promoters. The β-glucuronidase (GUS) histochemical analysis showed that MtML1 promoter can drive GUS gene expression in transiently transformed Nicotiana tabacum leaves under non-inducing condition. Furthermore, it can also control GUS expression in leaves and siliques rather than roots of the stably transformed Arabidopsis. More importantly, the leaf cross-section observations indicated that MtML1 exclusively expressed in the epiderm...
Source: Journal of Biotechnology - Category: Biotechnology Source Type: research