A new use of Agrobacterium plant growth regulator genes for plant bioengineering
Year: 2026
Type: article
Abstract: Delivery of biomolecules into plant vascular tissues remains a barrier to managing diseases caused by insect vector-borne pathogens and to modifying phenotypes of established perennial crops. Inspired by the vascularized growth of crown galls induced by Agrobacterium tumefaciens , we repurposed the bacterium’s plant growth regulator (PGR) genes to engineer autonomously dividing, transgene-expressing plant cell structures termed symbionts. A plant transformation vector (pSYM) incorporating the IaaM, IaaH, Ipt and gene5 cassette from A. tumefaciens strain C58 together with a gene of interest on the same transfer DNA was delivered to stems of herbaceous and woody dicots using disarmed A. tumefaciens strain EHA105. Symbiont morphology, vascular differentiation, transgene expression, molecular mobility and protein secretion were evaluated using microscopy, fluorescent reporters, dye tracing, RNA silencing assays and mass spectrometry-based proteomics. pSym inoculation reproducibly generated symbionts across diverse host plant species that were vascularly integrated into their host plants and transgene expression ranging from heterogeneous niches to more uniform patterns. Small molecules moved between symbionts and host vascular tissues, whereas larger proteins exhibited more restricted mobility. Post-transcriptional gene silencing signals moved freely throughout the symbiont and slightly into adjacent stem tissue. Under tested field and greenhouse conditions in potato and tomato, respectively, gall or symbiont formation had no negative impacts on plant growth or tuber and fruit yield. In vitro , symbiont cultures abundantly secreted recombinant protein into surrounding media. Together, these results establish symbionts as a modular, plant bioengineering platform capable of producing and potentially delivering biomolecules without modifying the host plant genome, providing a foundation for vascular-targeted therapeutics and phenotype modulation in crops.
Source: Frontiers in Plant Science
Authors: Michelle Heck, Marco Pitino, Samuel Coradetti, Stacy L. DeBlasio, W. Rodney Cooper, Lauren Shrum, Douglas Harper, Martin Stallone, Aspen Scott, Rachel Cook, Brian Rhodes, Samantha Sullivan, Elijah Schechter, Ellen Cochrane, Nicholas Larson, Guilherme Locatelli, Joanne Hodge, Magali Ferrari Grando, Li Wang, Meneka Ariyarante, Redeat Tibebu, Richard Stange, Kevin J. Howe, Ariana Makar, Douglas Stuehler, Luke Thompson, Ketan Shende, Matthew Hentz, Nichole Gaza, Chase Weeks-Purdy, Brian Chang, Ali Nikoomanzar, Lucy Bennett, Nursena Demirden, Wayne Hunter, James Thomson, Mark A. Ritenour, Lorenzo Rossi, Liliana M. Cano, Robert C. Adair, Eddie Stover, Cindy L. McKenzie, Randall Niedz, Robert G. Shatters
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $3,801
Award: G2241959441
OpenAlex ID: W7136343474