Transient expression of a green fluorescent protein in tobacco and maize chloroplast

Maize is considered to be one of the staple crops across the world. However, the limited production and unforeseen weather conditions often limit its availability. This is the major reason that scientists across the globe are working towards finding ways to improve the stability of the maize crop in harsh environmental conditions and its overall production rate. The improved quality of maize will not only help meet the demand of the ever-growing global population but will also overcome the shortage due to unanticipated environmental conditions. To achieve this, researchers tried for maize plastid transformation, which is not achieved effectively yet due to the recalcitrant conditions of the crop.

In the present study, researchers constructed two vectors containing homologous recombination sequences from maize and grass. These vectors are designed to later integrate into the chloroplast genome from an inverted repeat region. The vectors consist of two crucial genes mgfp5 and hph gene (as selection marker). The former gene is driven by Prrn, a leader sequence of the atpB gene and a terminator sequence from the rbcL gene. Whereas the later is driven by Prrn, a leader sequence from rbcL gene and a terminator sequence from the rbcL gene. The vectors were then used to transform the explants of maize, tobacco, and E.coli to assess the transitory expression. The expression levels were evident from the green and red fluorescent light when observed under the epiflourescence microscope.

The results of the study show the successful expression of both vectors, along with the presence of a reporter gene in all three organisms. This highlights the capability of vectors to express genes in the cell compartments. The results in the paper are the first report of transient expression of GFP in maize embryos, offering the opportunity to improve the recalcitrant crops genetically using biotechnological interventions. 

CRISPR/Cas9-mediated gene editing for the development of herbicide-resistant plants.

Application of CRISPR/Cas9-mediated gene editing for the development of herbicide-resistant plants.

Authors: Yun-Jeong Han, Jeong-Il Kim

The development of herbicide-resistant plants is the need of time to help the agriculture economy move ahead. Lack of this trait in plants can impact their growth during herbicide applications leading to loss of crops. Imparting herbicide-resistant traits using genetic engineering will not only help plants/ crops survive better but also control the unwanted weeds. For these reasons, researchers are developing new methods and technologies to pass on herbicide resistance traits in plants. The CRISPR/Cas9 based gene-editing technology is considered to be highly precise and effective to carry out modification at genetic levels offering great efficiency in enhancing the crops. In the present study, the researchers used CRISPR based gene-editing technology to confer herbicide-resistant traits in plants by targeting genes such as 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), acetolactate synthase (ALS), splicing factor 3B subunit 1 (SF3B1), and cellulose synthase A catalytic subunit 3 (CESA3). Besides this, researchers also added additional candidate genes to enhance the herbicide resistance properties of plants through inducing mutations using the CRISPR Cas9 gene-editing tool.

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