Identification and expression profiling of heteroglycan glucosidase 1 enzyme of Cenchrus americanus

Maltose metabolism is a critical process during plant growth, which provides energy during development and reproduction. To investigate maltose metabolism in C4 plants, we identified and analyzed the expression of the heteroglycan glucosidase 1 (HGL1) enzyme from Cenchrus americanus (L.) Morrone. The sequenced cDNA of CaHGL1 (3469 bp) encoded for a deduced protein of 1047 aa. Transmembrane topology revealed that CaHGL1 is a membrane-bound protein that comprises a signal peptide and a transmembrane helix. The promoter of CaHGL1 contains cis-elements related to the responses to light, abiotic stress and phytohormones. Real-time PCR revealed high expression in inflorescence and roots during the vegetative stage. Moreover, phytohormone treatments caused an activation of CaHGL1 expression in the seedling root and shoot by ABA, cytokinin, and BL, and an inhibition by JA in the seedling root and shoot. However, treatment with GA and IAA caused an activation in the CaHGL1 expression only in the shoot. Stress treatment induced the expression of CaHGL1 under drought, cold, and salt stress. The results of the current study give insight into the activity of the HGL1 enzyme in maltose metabolism under abiotic stress, which can aid in understanding the different metabolic pathways in Cenchrus americanus under stress.