Next Article in Journal
Fluorescence In Situ Hybridization (FISH) Analysis of the Locations of the Oligonucleotides 5S rDNA, (AGGGTTT)3, and (TTG)6 in Three Genera of Oleaceae and Their Phylogenetic Framework
Previous Article in Journal
Microbial Genes for a Circular and Sustainable Bio-PET Economy
Open AccessArticle

Construction of Marker-Free Genetically Modified Maize Using a Heat-Inducible Auto-Excision Vector

National Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
*
Author to whom correspondence should be addressed.
Genes 2019, 10(5), 374; https://doi.org/10.3390/genes10050374
Received: 22 February 2019 / Revised: 10 May 2019 / Accepted: 13 May 2019 / Published: 17 May 2019
(This article belongs to the Section Technologies and Resources for Genetics)
Gene modification is a promising tool for plant breeding, and gradual application from the laboratory to the field. Selectable marker genes (SMG) are required in the transformation process to simplify the identification of transgenic plants; however, it is more desirable to obtain transgenic plants without selection markers. Transgene integration mediated by site-specific recombination (SSR) systems into the dedicated genomic sites has been demonstrated in a few different plant species. Here, we present an auto-elimination vector system that uses a heat-inducible Cre to eliminate the selectable marker from transgenic maize, without the need for repeated transformation or sexual crossing. The vector combines an inducible site-specific recombinase (hsp70::Cre) that allows for the precise elimination of the selectable marker gene egfp upon heating. This marker gene is used for the initial positive selection of transgenic tissue. The egfp also functions as a visual marker to demonstrate the effectiveness of the heat-inducible Cre. A second marker gene for anthocyanin pigmentation (Rsc) is located outside of the region eliminated by Cre and is used for the identification of transgenic offspring in future generations. Using the heat-inducible auto-excision vector, marker-free transgenic maize plants were obtained in a precisely controlled genetic modification process. Genetic and molecular analyses indicated that the inducible auto-excision system was tightly controlled, with highly efficient DNA excision, and provided a highly reliable method to generate marker-free transgenic maize. View Full-Text
Keywords: marker-free; transgenic maize; egfp; heat-shock; recombination; cre/lox marker-free; transgenic maize; egfp; heat-shock; recombination; cre/lox
Show Figures

Figure 1

MDPI and ACS Style

Du, D.; Jin, R.; Guo, J.; Zhang, F. Construction of Marker-Free Genetically Modified Maize Using a Heat-Inducible Auto-Excision Vector. Genes 2019, 10, 374.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop