Food Chemistry: X (Jun 2019)

Ca2+ involved in GABA signal transduction for phenolics accumulation in germinated hulless barley under NaCl stress

  • Yan Ma,
  • Pei Wang,
  • Zhenxin Gu,
  • Yang Tao,
  • Chang Shen,
  • Yulin Zhou,
  • Yongbin Han,
  • Runqiang Yang

Journal volume & issue
Vol. 2

Abstract

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In this study, in order to investigate the role of Ca2+ in GABA signal transduction involved in phenolics accumulation in barley seedlings under NaCl stress, the seedlings were treated with exogenous GABA and its synthesis inhibitor, 3-mercaplopropionic acid (3-MP), as well as Ca2+ channel blockers La3+, Ca2+ chelator EGTA, and Ca2+ release channel inhibitor 2-aminoethoxydiphenyl borate (2-APB). The results showed that GABA significantly enhanced phenolics, calcium and calmodulin content. It also induced Ca2+ influx in barley root tips cells, and altered the distribution of Ca2+, making calcium precipitates more uniform and intensive. While, 3-MP treatment led to opposite changes, which suggested that GABA was essential for calcium content increase. In addition, accumulation of phenolics was inhibited by LaCl3, EGTA and 2-APB treatments, and this inhibition could be alleviated partly by exogenous GABA. Taken together, Ca2+ was involved in GABA signal transduction for phenolics accumulation in barley seedlings under NaCl stress. Keywords: GABA, Ca2+, Phenolics, NaCl stress, Germinated hulless barley