At a glance: AS109 gives transient expression in diverse crops, supports four assays in faba bean and lets us test NLR recognition across plant families.

AS109: transient gene expression across diverse crops

King, Lopez-Agudelo et al. PLOS Biology 24(10): e3004010, 15 October 2026. Methods and Resources article.

Read the paper · PDF · PubMed · Data on Zenodo · Peer review history · bioRxiv preprint

By the numbers

  • 30 angiosperm species screened

  • 6 agrobacterial strains compared side by side in every leaf

  • 7 plant families where AS109 delivered the reporter

  • 23 apoplastic elicitors screened in faba bean

In plain language

Gene delivery into leaves is routine in a few model plants and often difficult in crops. AS109 is a disarmed derivative of Rhizobium rhizogenes A4 that does it quickly, and in side-by-side leaf tests it usually outperformed the standard Agrobacterium strains used in labs.

We screened 30 species and found that AS109 delivered a reporter in seven plant families. We then used it to set up assays in faba bean, a legume crop, where it supports protein localisation, gene silencing and cell-death assays. Lettuce is a second example. That means immune receptors and infection biology can be tested directly in crops, not only in model plants.

What we found

  • AS109 works across many dicot families and usually beats standard lab strains.

  • Faba bean supports protein localisation, RNAi silencing and cell-death assays, and lettuce works as a second case.

  • A singleton NLR (Rpi-vnt1) and a sensor-helper pair (Rx with NRC4) keep their recognition specificity in faba bean.

  • The potato protein StREM1.3 marks the membrane around Phytophthora palmivora haustoria in faba bean, which gives a view of the infection interface.

Figures

Figure 1. Rhizobium rhizogenes AS109 enables transient gene expression across diverse dicot species. From King, Lopez-Agudelo et al., PLOS Biology 2026 (CC BY 4.0). Click to enlarge.

Figure 2. AS109 facilitates functional assays in the non-model species faba bean. From King, Lopez-Agudelo et al., PLOS Biology 2026 (CC BY 4.0). Click to enlarge.

Figure 3. Autoactive helper NLRs cause cell death and form puncta at the plasma membrane in faba bean. From King, Lopez-Agudelo et al., PLOS Biology 2026 (CC BY 4.0). Click to enlarge.

Figure 4. A singleton NLR and a sensor-helper NLR pair from Solanaceae perform their cell death functions in faba bean. From King, Lopez-Agudelo et al., PLOS Biology 2026 (CC BY 4.0). Click to enlarge.

Figure 5. AS109-mediated expression reveals a novel host-pathogen interface in faba bean. From King, Lopez-Agudelo et al., PLOS Biology 2026 (CC BY 4.0). Click to enlarge.

Data, citation and credit

Source data are on Zenodo (10.5281/zenodo.20056567). Cite as: King F, Lopez-Agudelo JC, Stephens C, et al. A broad-host-range Rhizobium rhizogenes strain enables transient expression across diverse crop species. PLOS Biology 24(10): e3004010 (2026). The article is CC BY 4.0. Funding and competing interests are declared in the paper.

Corresponding authors: Lida Derevnina, Chih-Hang Wu and Tolga Bozkurt.

Constructs and strains from the paper are available on request, subject to a Material Transfer Agreement (MTA). Requests go to the Imperial College Research Office Contracts Team or to the Academia Sinica Department of Intellectual Property and Technology Transfer, through its online portal. Dr Chih-Hang Wu at Academia Sinica handles requests for the AS109 strain.