Expression characteristics and functional analysis of the LcCBF6 gene from Leymus chinensis

doi:10.11686/cyxb2020375

Abstract

Abstract:

Chinese wild rye（Leymus chinensis） is an important forage grass in China， and is also ecologically important because it has high tolerance to saline-alkali soil， drought， and low temperature stresses. Chinese wild rye can therefore be an excellent gene pool for molecular breeding to enhance stress tolerance. CBF/DREBs belong to the AP2 transcription factor family and play an important role in plant stress resistance. In this study， the LcCBF6（L. chinensis C-repeat binding factor 6） gene was cloned. It encoded 245 amino acids and contained the AP2 domain. Amino acid sequence alignment showed that the LcCBF6 gene had high sequence conformity to its homologous proteins from Agropyron mongolicum （92%） and Secale cereale （91%）. Expression analysis confirmed that LcCBF6 gene was expressed in roots， leaves and seeds， and was significantly induced by salt stress. Overexpression of LcCBF6 significantly enhanced the salt resistance of transgenic Arabidopsis thaliana. Under the salt stress， the number of green cotyledons， the root length， plant biomass and survival rate of transgenic lines were all significantly higher than in the wild type. The results suggest that the LcCBF6 gene might play an important positive role in salt stress tolerance， and be an excellent gene to utilize for enhancing stress tolerance in forages and other important crops.

Key words: Leymus chinensis, CBF gene family, LcCBF6, transgene, salt tolerance

Qian LI, Xiao-xia LI, Li-qin CHENG, Shuang-yan CHEN, Dong-mei QI, Wei-guang YANG, Li-jun GAO, Ba-yin XIN, Gong-she LIU. Expression characteristics and functional analysis of the LcCBF6 gene from Leymus chinensis[J]. Acta Prataculturae Sinica, 2021, 30(10): 105-115.

Figures/Tables 7

Fig.1 Sequence alignment analysis of LcCBF6 gene coding protein

Fig.2 LcCBF6 phylogenetic tree

Fig.3 Expression patterns of LcCBF6 gene

Fig.4 Identification of plant expression vector pCAMBIA3301-LcCBF6 by enzyme digestion and PCR identification of transgenic line

Fig. 5 Effects of LcCBF6-over-expressing Arabidopsis seed germination under NaCl stress （mean±SD， n=3）

Fig.6 Salt-resistant phenotype of LcCBF6-over-expressing Arabidopsis in seedlings stage （mean±SD， n=3）

Fig.7 Effects of NaCl stress on root length of LcCBF6-over-expressing Arabidopsis plants （mean±SD， n=3）

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