Study of pectin methylesterase PtoPME34-1 regulating drought resistance in Populus tomentosa

Abstract:

To explore the function of pectin methylesterase (PME) in forest plants, in this study, we cloned the Arabidopsis thaliana PME34 homologous gene PtoPME34-1 from Populus tomentosa, and elucidated the biological function of this gene in Populus tomentosa. Bioinformatics analysis shows that the similarity between the PtoPME34-1 gene of Populus tomentosa and the PtrPME34-1 of Populus tomentosa is 100%, and the similarity of the sequence with AtPME34 of Arabidopsis thaliana was 93%. Tissue specific expression analysis shows that PtoPME34-1 gene is expressed in all tissues, with higher expression levels in the basal stems and xylem, and the lowest expression level in the old leaves. The results of subcellular localization show that GFP- labeled PtoPME34-1-GFP fusion protein is localized in the cell wall of tobacco leaves. The overexpression of PtoPME34-1 gene significantly improved drought resistance of Populus tomentosa. The double mutants of Populus tomentosa PtoPME34-1 and PtoPME34-2 increased the degree of pectin methylesterification level and drought resistance. These results confirm that PtoPME34-1 plays an important role in regulating plant development and drought stress resistance.