Improvement of Soybean Agrobacterium-Mediated Transformation Efficiency by Adding Glutamine and Asparagine into the Culture Media.

Weiwei Yao,Tianfu Han,Shi Sun,Wensheng Hou,Yupeng Cai,Cunxiang Wu,Li Chen,Xiujie Liu,Chen Guo,Bingjun Jiang

doi:10.3390/ijms19103039

Abstract

As a genetically modified crop, transgenic soybean occupies the largest global scale with its food, nutritional, industrial, and pharmaceutical uses.Efficient transformation is a key factor for the improvement of genetically modified soybean. At present, the Agrobacterium-mediated method is primarily used for soybean transformation, but the efficiency of this method is still relatively low (below 5%) compared with rice (above 90%). In this study, we examined the influence of l-glutamine and/or l-asparagine on Agrobacterium-mediated transformation in soybean and explored the probable role in the process of Agrobacterium-mediated transformation. The results showed that when the amino acids l-glutamine and l-asparagine were added separately or together to the culture medium, the shoot induction frequency, elongation rate, and transformation frequency were improved. The combined effects of l-glutamine and l-asparagine were better than those of l-glutamine and l-asparagine alone. The 50 mg/L l-glutamine and 50 mg/L l-asparagine together can enhance the transformation frequency of soybean by attenuating the expression level of GmPRs (GmPR1, GmPR4, GmPR5, and GmPR10) and suppression of the plant defense response. The transgene was successfully transmitted to the T1 generation. This study will be useful in genetic engineering of soybean.

Highlights

Soybean (Glycine max (L.) Merrill) is one of the world’s most important oil and protein crops, serving as a food source for humans and for animal forage, and it has industrial uses [1]
The shoot induction frequency was approximately 68.9% when no L-asparagine or L-glutamine was added to the media, and the shoot induction frequencies were approximately 77.9% and 84.3% in media supplemented with L-asparagine or L-glutamine, respectively
The results demonstrated that the improved conditions can be applied to more soybean cultivars

Summary

Introduction

Soybean (Glycine max (L.) Merrill) is one of the world’s most important oil and protein crops, serving as a food source for humans and for animal forage, and it has industrial uses [1]. Transgenic soybean is a genetically modified (GM) crop that occupies the largest global scale with its food, nutritional, industrial, and pharmaceutical uses. From 1996 to 2015, approximately 1030 million hectares of GM soybean were planted and more than 50 billion US dollars were generated as income to farmers. Valuable genes and efficient transformation are the key factors for the improvement of GM soybean. As rice varieties are becoming more popular model plants, research on soybeantransgenic lines and the improvement of soybean agronomic characteristics has fallen behind, and that may be possibly due to genome complexity and the lower transformation efficiency [3]

Methods

Results

Discussion

Conclusion