MutChromSeq: A New Technique for Fast Isolation of Genes

           With the ever-growing human population, it is important to produce enough food to meet the demand. The main source of food production is crops; therefore, it is vital that plants have high yields. Wheat and barley are two major crops found worldwide because they can survive in various environments, result in high yields, and contain many nutrients. If these traits could be controlled, then the yields would increase and there would be food security on a global scale. To control these traits, we must know the genes responsible for them. All we need to do is locate these genes in wheat and barley. This is easier said than done. Wheat and barley have large genomes and large regions of suppressed recombination. This makes it very time-consuming and expensive to use traditional map-based gene isolation. Additionally, obtaining sequences of whole genomes from several mutants is not feasible because comparing large datasets is challenging and costly. There are multiple techniques that can be used to make the sequences of the wheat and barley genomes less complex. However, these methods often result in some sequences being overlooked. Wulff et. al developed a new technique to reduce the complexity of the wheat and barley genomes that does not overlook certain sequences.

Their technique, MutChromSeq, involves flow sorting and comparing the sequences of various mutant chromosomes. This method identifies the mutation and eliminates the need for fine mapping and recombination. MutChromSeq was used to reclone the barley Eceriferum-q gene and clone de novo the wheat Pm2 gene. Even though a false positive was included in the Eceriferum-q example, the correct gene was still identified. The chromosomes were isolated using fluorescent markers. The sequences of the six mutant chromosomes were compared to the wild-type chromosomes.

This approach includes mutagenesis, the reduction of genome complexity, and high-throughput screening. Therefore, the plant species must be able to undergo mutagenesis. Also, the phenotype of the target gene and the chromosome the gene is on must be known. MutChromSeq can be used on genes that meet these requirements, and the method is quick and inexpensive. This method makes it possible to isolate and clone genes that were very difficult to manage in the past.

The researchers introduce a very powerful technique for gene isolation. For genes that could not be easily cloned before, there is now a fast and inexpensive technique that can be used. This is especially impactful for the production of crops. With this new approach, the genes that produce beneficial traits in crops can be targeted. Thus, crops can be improved to better withstand pests and changes in weather. This is very encouraging for the future of food production.

Reference:

Javier Sánchez-Martín, Burkhard Steuernagel, Sreya Ghosh, Gerhard Herren, Severine Hurni, Nikolai Adamski, Jan Vrána, Marie Kubaláková, Simon G. Krattinger, Thomas Wicker, Jaroslav Doležel, Beat Keller, Brande B. H. Wulff. “Rapid gene isolation in barley and wheat by mutant chromosome sequencing.” Genome Biology, 2016.

http://genomebiology.biomedcentral.com/articles/10.1186/s13059-016-1082-1