CaM enhances chilling tolerance of peach fruit by regulating energy and GABA metabolism
Bing Xie, Chen Ling, Shunqing Hu, Yuanyuan Hou, Yonghua Zheng and Peng Jin
Postharvest Biology and Technology, Volume 181, November 2021, 111691
2021
บทคัดย่อ
The effects of calcium chloride (CaCl2), calmodulin antagonist trifluoperazine (TFP) and different storage temperatures on chilling injury (CI) of peach fruit during postharvest storage were studied. The results showed that 0 °C storage and CaCl2 treatment reduced the CI index, reduced the ion leakage and maintained the integrity of cell membrane. Storage at 0 °C and CaCl2 treatment increased calmodulin (CaM) expression and protein content, energy charge (EC), adenosine triphosphate (ATP) content and adenosine diphosphate (ADP) content. At the same time, it also promoted the expression and activity of Ca2+-ATPase and other enzymes related to energy metabolism. In addition, storage at 0 °C and CaCl2 treatment promoted the expression and activity of glutamic acid decarboxylase (GAD), and increased the content of γ-aminobutyric acid (GABA) and the expression of GABA transaminase (GABA-T). On the contrary, TFP treatment significantly increased CI index and ion leakage, significantly inhibited PpCaM expression and protein content, and decreased EC and GABA content. Moreover, the molecular properties of PpCaM were studied. The results showed that PpCaM was a highly conserved hydrophilic protein, located on the nucleus and plasma membrane. PpCaM could induce the expression of PpCa2+-ATPase, increase the activity of Ca2+-ATPase, and participate in the regulation of energy metabolism. In addition, PpCaM could activate the activity of PpGAD, promote the synthesis of GABA, and participate in the regulation of GABA metabolism. These results suggested that 0 °C storage and CaCl2 treatment promoted the expression of PpCaM and increased the protein content of PpCaM, suggesting PpCaM enhanced the cold resistance and reduced the occurrence of CI by participating in the regulation of energy metabolism and GABA metabolism.