Soybean is an important crop for food, oil and feed worldwide. However, production of soybean is very limited in China. To increase the soybean yield, it is urgent to create soybean varieties, which can grow and adapt to the huge areas of salt, alkaline and arid lands.
Recently, a team led by Prof ZHANG Jinsong, from State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology (IGDB), Chinese Academy of Sciences (CAS), reported roles and mechanisms of a transcriptional regulator GmZF351 in salt and drought stress tolerance in stable transgenic soybean plants. This work entitled “Zinc-finger protein GmZF351 improves both salt and drought stress tolerance in soybean” was published online (
https://doi.org/10.1111/jipb.13474) in
Journal of Integrative Plant Biology.
ZHANG’s group previously discovered that the gene is highly expressed in soybean seeds and promotes oil accumulation in developing seeds. This gene shows barely no expression or very low expression at seedling and/vegetative stage. However, under salt and other stresses, the gene is activated for stress tolerance in soybean. The authors found that histone demethylation may be involved such a transition. Under normal condition, the histones are highly methylated at the promoter region of the GmZF351 gene. Up salt treatment, the two histone demethylase genes JMJ30-1 and JMJ30-2 are activated, leading to removal of the histone H3K27me3 at GmZF351 promoter and hence activation of the gene.
The study further dissected the cis-elements bound by the zinc finger protein GmZF351. The element contains two of the motif CT(G/C)(T/A)AA for recognition. All the downstream genes involved in oil biosynthesis and stress tolerance have such features in their promoter regions. However, the GmZF351 activated different sets of genes for lipid accumulation in soybean seeds and in response to salt and drought stresses.
For plants, it is expensive and costs much energy to resist stress and survive for future generation. Therefore, stress tolerance and yield/storage accumulation must be fully considered during plant growth and development to complete the life cycle. The presently identified gene GmZF351 may promote both oil accumulation in seeds and stress tolerance in seedlings, balancing the two important biological processes in different organs and at different developmental stages.
Understanding of the GmZF351 dual functions may shed light on the balancing mechanism of a crop for seed yield/storage and survival during crop domestication, and provide inspiring basis and insights for creating new soybean varieties suitable for unfavorable salt lands and environments.
Dr WEI Wei from IGDB, Dr LU Long from Fujian Agriculture and Forestry University and graduated student Dr BIAN Xiaohua contributed equally to the paper. Professors ZHANG Jinsong Zhang, CHEN Shouyi and ZHANG Wanke are corresponding authors. Professors LAI Yongcai and MAN Weiqun from Heilongjiang Academy of Agricultural Sciences also participated in the work. This study is supported by National Natural Science Foundation of China and the Key Project from CAS.
Figure, Performance of the GmZF351 transgenic soybean plants and its working model in stress tolerance. (Image by IGDB)
A, Performance of the GmZF351 transgenic plants under salt stress. Jack is the original control cultivar. Null is segregated from heterozygous transgenic plants and without transgene insertion. OE-34/40/73 indicate independent homozygous transgenic lines. B, Performance of the transgenic plants under drought stress. C, Comparison of water loss in detached leaves at different times. D, A working model of GmZF351 in stress response. Under normal well-watered condition, the histones H3K27 is highly methylated at the promoter region of GmZF351, blocking gene expression. Under stress, the histone demethylase JMJ30 is induced and the methylation of H3K27 is reduced, allowing activation of GmZF351 and subsequent downstream gene expression for stomata closure and stress tolerance.
Contact:
Dr. ZHANG Jinsong
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences
CAS
中文
Figure, Performance of the GmZF351 transgenic soybean plants and its working model in stress tolerance. (Image by IGDB)A, Performance of the GmZF351 transgenic plants under salt stress. Jack is the original control cultivar. Null is segregated from heterozygous transgenic plants and without transgene insertion. OE-34/40/73 indicate independent homozygous transgenic lines. B, Performance of the transgenic plants under drought stress. C, Comparison of water loss in detached leaves at different times. D, A working model of GmZF351 in stress response. Under normal well-watered condition, the histones H3K27 is highly methylated at the promoter region of GmZF351, blocking gene expression. Under stress, the histone demethylase JMJ30 is induced and the methylation of H3K27 is reduced, allowing activation of GmZF351 and subsequent downstream gene expression for stomata closure and stress tolerance.Contact:Dr. ZHANG JinsongInstitute of Genetics and Developmental Biology, Chinese Academy of SciencesEmail: jszhang@genetics.ac.cn