Unlocking genetic diversity: A-to-K base editing achieves new milestones
en-GBde-DEes-ESfr-FR

Unlocking genetic diversity: A-to-K base editing achieves new milestones

11/11/2024 TranSpread

Single nucleotide polymorphisms (SNPs) are critical for generating genetic diversity in plants, influencing essential traits like disease resistance and yield. Traditional base-editing tools—adenine base editors (ABEs) and cytosine base editors (CBEs)—mainly enable A-to-G and C-to-T conversions, limiting the range of genetic modifications possible. This narrow scope restricts researchers’ ability to generate diverse SNPs, thus constraining the potential for comprehensive crop improvement. To address this, researchers have sought more versatile systems capable of broader base substitutions, which could boost genetic variation and accelerate advances in plant breeding.

Researchers from the Chinese Academy of Agricultural Sciences, alongside partners, recently published findings (DOI: 10.1093/hr/uhad250) in Horticulture Research on December 2, 2023,on their new adenine-to-tyrosine (A-to-K) base editor (AKBE) system for plants. This innovative tool enables efficient A-to-T and A-to-C base substitutions, which were successfully tested on multiple loci in rice and tomato. By integrating a protospacer adjacent motif (PAM)-less Cas9 variant, AKBE broadens its target range and achieves heritable, precise edits. Providing a powerful resource for enhancing genetic diversity, this tool marks a substantial advance in plant biotechnology. The study, published in January 2024, represents a critical breakthrough for crop breeding.

In developing the AKBE system, the researchers engineered a mechanism that combines adenosine deaminase with a modified DNA glycosylase (MPG), enabling both A-to-G and A-to-T/C base substitutions with significant efficiency. The use of a PAM-less Cas9 variant further expanded target accessibility, allowing edits in previously challenging genomic regions. Testing on 228 T0 rice plants and 121 T0 tomato plants, AKBE achieved conversion rates averaging 41% for A-to-G and up to 25.9% and 10.5% for A-to-T in rice and tomato, respectively. Additionally, a rice-optimized AKBE enabled A-to-C edits with 1.8% efficiency, further diversifying mutation types. These edits were confirmed to be heritable across generations. Notably, AKBE’s A-to-T editing can create early stop codons, effectively disrupting gene function—an invaluable capability for gene knockout research. For example, edits in the beta-carotene biosynthesis gene (β-OsLCY) in rice led to observable albino phenotypes, affirming successful gene disruption.

Dr. Yifu Tian, a lead researcher from the Chinese Academy of Agricultural Sciences, highlighted the significance of AKBE’s capabilities: “The AKBE system significantly expands the scope of single-base editing in plants, allowing us to explore gene functions with precision and efficiency. By enabling heritable A-to-T and A-to-C conversions, this tool enhances our ability to create genetically diverse crops and opens new possibilities for agricultural biotechnology.”

The AKBE system has substantial potential in advancing crop breeding by enabling precise genetic modifications that could improve resistance to environmental stressors, diseases, and pests in staple crops. This innovation is particularly relevant for developing crop varieties suited to changing climates and addressing global food security challenges. By facilitating controlled gene disruptions, AKBE provides breeders with a precise tool to refine traits like yield, nutritional content, and adaptability. Additionally, as a resource for functional genomics, AKBE allows researchers to explore gene functions in detail, supporting the development of sustainable and resilient agricultural practices.

###

References

DOI

10.1093/hr/uhad250

Original Source URL

https://doi.org/10.1093/hr/uhad250

Funding information

This study was supported by the China Postdoctoral Science Foundation (No. BX20220098 and No. 2022M720973) and the Hainan Yazhou Bay Seed Laboratory (B22C1000P) to Y.T., Nanfan special project, CAAS (No. ZDXM2314) to M.W., and the National Natural Science Foundation of China (No. 32188102) to J.-K.Z.

About Horticulture Research

Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2022. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.

Attached files
  • Heritable and efficient A-to-K editing induced by AKBEs in rice.
11/11/2024 TranSpread
Regions: North America, United States, Asia, China
Keywords: Science, Agriculture & fishing, Life Sciences

Disclaimer: AlphaGalileo is not responsible for the accuracy of news releases posted to AlphaGalileo by contributing institutions or for the use of any information through the AlphaGalileo system.

Testimonials

For well over a decade, in my capacity as a researcher, broadcaster, and producer, I have relied heavily on Alphagalileo.
All of my work trips have been planned around stories that I've found on this site.
The under embargo section allows us to plan ahead and the news releases enable us to find key experts.
Going through the tailored daily updates is the best way to start the day. It's such a critical service for me and many of my colleagues.
Koula Bouloukos, Senior manager, Editorial & Production Underknown
We have used AlphaGalileo since its foundation but frankly we need it more than ever now to ensure our research news is heard across Europe, Asia and North America. As one of the UK’s leading research universities we want to continue to work with other outstanding researchers in Europe. AlphaGalileo helps us to continue to bring our research story to them and the rest of the world.
Peter Dunn, Director of Press and Media Relations at the University of Warwick
AlphaGalileo has helped us more than double our reach at SciDev.Net. The service has enabled our journalists around the world to reach the mainstream media with articles about the impact of science on people in low- and middle-income countries, leading to big increases in the number of SciDev.Net articles that have been republished.
Ben Deighton, SciDevNet

We Work Closely With...


  • BBC
  • The Times
  • National Geographic
  • The University of Edinburgh
  • University of Cambridge
  • iesResearch
Copyright 2024 by AlphaGalileo Terms Of Use Privacy Statement