2024-02-10 09:45:32
K-State Researchers Reduce Gluten Content in Bread Wheat While Preserving Dough Quality
Pat Melgares, service de presse de K-State Research and Extension*
K-State researchers used the gene-editing technique known as CRISPR-Cas9 to reduce the presence of two types of gluten-encoding genes in the wheat genome.
This advancement could make wheat-based foods safer for people sensitive to gluten.
December 11, 2023
MANHATTAN, Kan. – Kansas State University researchers have made a breakthrough in developing wheat-based foods with less gluten, a discovery that could lessen the harmful effects for people with celiac disease or other autoimmune diseases.
Scientists from the K-State Wheat Genetic Resources Center and the USDA Agricultural Research Service, in partnership with Kansas Wheat, have successfully used a gene-editing technique known as CRISPR-Cas9 to reduce the presence of two types of genes encoding gluten, called gliadins, known to be rich in immunoreactive peptides, the amino acids that form proteins.
Gluten is a protein often found in wheat, barley and rye. When people with celiac disease eat gluten, their bodies trigger an immune response that attacks the small intestine and the small finger-like projections called villi that help the body absorb nutrients properly.
According to the Celiac Disease Foundation, celiac disease affects 1 in 100 people worldwide, but only 30% of them are correctly diagnosed.
“We were very surprised to find that once these genes were edited, we reduced the immunotoxicity caused by gliadin genes in wheat by 47-fold,” said Dr. Eduard Akhunov, Distinguished Professor of the Department of Plant Pathology. from K-State and director of the Wheat Genetics Resource Center.
Mr. Akhunov leads a group of scientists who apply advanced genomics, genetics and genome editing methods to improve wheat. In this project, gluten gene editing was carried out by postdoctoral researcher Zitong Yu.
Gluten will probably never be completely eliminated from wheat, Akhunov said, because it is important for bread making. Gluten gives texture, flavor and moisture to products such as bread, bagels, pastries, noodles, etc.
“In our edited lines, we also found that despite a reduction in toxicity (reduction due to lower levels of toxic gluten molecules), we did not see a reduction in dough quality , which is important for bread making,” Mr. Akhunov said. “This is extremely important. We achieved these two seemingly contradictory goals: reducing toxicity while maintaining the ability to produce quality pulp. »
Mr. Akhunov added that although the reduced levels of gluten obtained in this study will not make wheat immediately safe for people with severe celiac disease, “it is important to move forward ‘Before “.
“Wheat varieties with reduced toxicity levels will help expand wheat product options for people with minor gluten-related issues,” he said. “The knowledge gained from this research could eventually pave the way for the development of new varieties that are safer for people with celiac disease. »
The very nature of scientific studies and wheat breeding means that gluten-reduced varieties may not be available to consumers for many years. Mr. Aaron Harries, vice president of research and operations for Kansas Wheat, said this trait would not be included in all new varieties and “would most likely be grown under contract with food manufacturers.”
“Wheat research is focused on developing new varieties that meet consumer demands, both domestically and internationally,” Mr Harries said. “Developing safer wheat for people with celiac disease reduces the number of consumers forced to consider alternatives to wheat. »
He adds: “In Kansas, many wheat farmers and their family members have celiac disease. It is ironic and unfortunate that they earn their living by growing wheat, but cannot consume wheat-based foods. Most consumers would prefer not to give up wheat-based foods in their diet. The development of wheat varieties that can be consumed by people with celiac disease would make their lives much easier. »
CRISPR-Cas9 is a genome editing tool that is faster, cheaper and more precise than previously used genome engineering methods. Akhunov says his research team worked with a common wheat cultivar called Fielder, which is suitable for genome editing.
K-State’s research, which was funded by Kansas Wheat, the USDA National Institute of Food and Agriculture and the Bill and Melinda Gates Foundation, is published in the Nov. 17 issue of Plant Biotechnology Journal.
_____________
* Source : K-State researchers lower gluten content, maintain dough quality in bread wheat
My note: Here is the summary (trimmed, and subject to the well-known adage of translators) of “CRISPR-based editing of the ω- and γ-gliadin gene clusters reduces wheat immunoreactivity without affecting grain protein quality” (the edition based on CRISPR of ω and γ-gliadin gene clusters reduces wheat immunoreactivity without affecting grain protein quality) by Zitong Yu, Ural Yunusbaev, Allan Fritz, Michael Tilley, Alina Akhunova, Harold Trick, Eduard Akhunov:
“Wheat immunotoxicity is associated with an abnormal response to gluten-derived peptides. Attempts to reduce immunotoxicity through breeding and biotechnology often affect pulp quality.
Here, CRISPR-Cas9 multiplexed editing of the Fielder cultivar was used to modify gluten-encoding genes, focusing specifically on copies of the ω and γ-gliadin genes, which were identified as being abundant in peptides immunoreagents based on the analysis of wheat genomes assembled using long-read sequencing technologies.
Whole genome sequencing of an edited line showed mutation or deletion of almost all copies of the ω-gliadin gene and half of the copies of the γ-gliadin gene and confirmed the absence of editing in the genes α/β-gliadin.
The estimated 75% and 64% reduction in ω- and γ-gliadin content, respectively, did not have a negative impact on the quality characteristics of grain and dough proteins from the perspective of l end use.
A 47-fold reduction in immunoreactivity compared to an unedited line was demonstrated using antibodies against immunotoxic peptides.
Our results indicate that targeted CRISPR editing of ω- and γ-gliadin gene copies, determined to be abundant in immunoreactive peptides by analysis of high-quality genome assemblies, is an effective way to reduce the immunotoxicity of wheat cultivars while minimizing the impact of editing on protein quality.
We can also (re)read “CRISPR can bring science closer to the consumer” and “Three widespread myths about wheat and the role of gluten”.
1707710930
#KState #Researchers #Reduce #Gluten #Content #Bread #Wheat #Preserving #Dough #Quality