biologia plantarum

Biologia plantarum 66:83-95, 2022 | DOI: 10.32615/bp.2021.063

PgLEA, a gene for late embryogenesis abundant proteinfrom Panax ginseng, enhances drought and salt tolerancein transgenic Arabidopsis thaliana

W.H. LIAN¹, R. SUN¹, L.X. ZHANG², T.X. SUN¹, F. HUI¹, L. FENG¹, Y. ZHAO^{1, *}

¹ Jilin Ginseng Academy, Changchun University of Chinese Medicine, Changchun 130117, P.R. China

² Guoxin Ze Ding International Medical Technology Co. Ltd, Beijing 100041, P.R. China

Late embryogenesis abundant (LEA) proteins are important for promoting the growth and stress tolerance of plants. They are widely involved in plant growth regulation and responses to hormones and environmental factors. However, knowledge of the functions of the LEA gene in ginseng species remains limited. In this study, a Panax ginseng LEA gene (PgLEA) expression vector was constructed, and stable transgenic Arabidopsis lines were established. The PgLEA protein was classified in the LEA-2 subgroup. Reverse-transcription quantitative PCR analysis showed that the expression of PgLEA increased under 300 mM NaCl or 10 % (m/v) polyethylene glycol treatments. Under salt and osmotic stresses, overexpression of PgLEA in transgenic Arabidopsis plants improved germination rate, root length, and survival rate compared to wild-type plants. In response to drought or salt stress, transgenic plants increased proline accumulation, decreased malonaldehyde content and ion leakage. Furthermore, the transgenic plants exhibited significantly increased activity of superoxide dismutase, peroxidase, and catalase, and reduced accumulation of hydrogen peroxide and superoxide. Moreover, overexpression of PgLEA affected the expression of genes related to salt/drought stress. Taken together, PgLEA is a positive regulator of drought and salinity stress, and positively functioned in pleiotropic effects through regulating osmotic balance, reactive oxygen species scavenging and inducing transcription of stress-related genes. PgLEA may enable ginseng plants to adapt to adverse environments. The data presented herein imply that PgLEA may be useful for breeding new stress-tolerant ginseng cultivars.

Keywords: CAT, drought stress, malondialdehyde, Panax ginseng, PgLEA, POD, proline, salt stress, SOD, transgenic Arabidopsis thaliana.

Received: June 17, 2021; Revised: October 18, 2021; Accepted: October 22, 2021; Published online: April 1, 2022  Show citation