First transcription atlas of all wheat genes expands prospects for research and cultivation
Today the complete wheat genome (Triticum aestivum) has been published in “Science”. This sequence is the “anchor genome” for capturing the complete genetic diversity of wheat, which is a global food crop. A second publication in the same magazine describes the first opportunities this will create for scientists and practitioners.
Knowledge of the function of the genes, if possible all genes, in an organism is crucial. The expression of genes at various points in time, in various organs and under different environmental influences is a starting point for acquiring this knowledge. The transcription atlas now published for the wheat genome shows the direction in which research is developing.
Under the leadership of the John Innes Centre in Norwich (England), scientists from seven countries and 17 research institutes took part in the study. The German researchers were from the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) in Gatersleben and the Helmholtz Centre in Munich. For their study, the scientists analysed over 800 hundred expression data sets from 28 studies. They combined these with the fully annotated genome sequence to create a transcription atlas. The challenge here was not only the size but also the particular structure of the wheat genome. The wheat genome is polyploid, and is composed of three individual genomes with different antecedents.
In their study, the scientists give a very comprehensive insight into the spatiotemporal transcription landscape of polyploid wheat. “For the first time we are in a position to assign the proportions in the expression of characteristics to individual sub-genomes and to analyse the gene expression with the help of regulatory networks,” says Prof. Dr. Andrea Bräutigam (University of Bielefeld since October 2017), who participated in the project at the Leibniz Institute for Plant Genetics and Crop Plant Research. “Striking is, that major differences in gene expression exist particularly at the ends of the chromosomes, coding for agronomically important traits.”, continues Bräutigam. The pre-condition for the study was the exact annotation of sequences. This took place at the Helmholtz Centre in Munich. “Annotation of the genes, and the creation of family trees is the basis for clarifying structure and function. We were able to identify the gene loci precisely with specially developed algorithms,” according to Dr. Daniel Lang of the Helmholtz Centre in Munich.
Prof. Dr. Cristobal Uauy, Principal Investigator of the study at the John Innes Centre, says: “Our understanding of genomes has led to a dramatic progress in breeding and cultivation practices for other crops such as maize or rice. With the complete wheat genome available now, and follow-up work, it will be possible to identify genes in wheat more precisely and faster. This knowledge will help researchers and growers to use the allelic variations of polyploid wheat to improve targeted characteristics.”
Prof. Dr. Andrea Bräutigam Phone: (+49) (0)521 106 8753
Dr. Manuel Spannagl, Helmholtz Zentrum München - German Research Center for Environmental Health, Research Unit Plant Genome and Systems Biology, Ingolstädter Landstraße 1, 85764 Neuherberg, Tel. +49 89 3187 3584, +49 89 3187 3948,
Dr. Daniel Lang, Tel. +49 89 3187 3583
Prof. Dr. Cristobal Uauy
R. H. Ramírez-González et al. (2018): The transcriptional landscape of polyploid wheat (http://science.sciencemag.org/cgi/doi/10.1126/science.aar6089). Science, DOI: 10.1126/science.aar6089