Protein Expression Changes in Anther Callus of Ginseng during Low‐Temperature Acclimation

ABSTRACT Low‐temperature acclimation is one of the main methods of improving the cryopreservation of anther callus of ginseng ( Panax ginseng C. A. Mey.), particularly the callus survival rate. To investigate the molecular adaptation mechanisms of callus to low temperature, calli were induced from anthers and cultured at optimal temperature (25°C) for 15 d. Half of the calli were transferred to conditioned petri dishes stored at 4°C for different days. The optimal treatment time at 4°C was estimated based on the triphenyltetrazolium chloride value and survival rate of callus. Proteomic analysis showed that the abundance of 43 protein spots significantly changed ( p < 0.5) under 4°C acclimation, and they were identified using mass spectrometry. The proteins were found to be involved in stress response and defense, carbohydrate metabolism, amino acid and protein biogenesis and degradation, molecular chaperone, electron transport coupled with adenosine triphosphate (ATP) synthesis, and cellular processes as well as nucleotide metabolism. The results suggested that the enhancement of stress response, organic metabolism, ATP synthesis, and molecular chaperoning played important roles in the adaptation of ginseng anther callus to low temperature.