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Summary Integration ofAgrobacterium tumefacienstransferred DNA (T‐DNA) into the plant genome is the last step required for stable plant genetic transformation. The mechanism of T‐DNA integration remains controversial, although scientists have proposed the participation of various nonhomologous end‐joining (NHEJ) pathways. Recent evidence suggests that inArabidopsis, DNA polymerase θ (PolQ) may be a crucial enzyme involved in T‐DNA integration.We conducted quantitative transformation assays of wild‐type andpolQmutantArabidopsisand rice, analyzed T‐DNA/plant DNA junction sequences, and (forArabidopsis) measured the amount of integrated T‐DNA in mutant and wild‐type tissue.Unexpectedly, we were able to generate stable transformants of all tested lines, although the transformation frequency ofpolQmutants was c.20% that of wild‐type plants. T‐DNA/plant DNA junctions from these transformed rice andArabidopsis polQmutants closely resembled those from wild‐type plants, indicating that loss of PolQ activity does not alter the characteristics of T‐DNA integration events.polQmutant plants show growth and developmental defects, perhaps explaining previous unsuccessful attempts at their stable transformation.We suggest that either multiple redundant pathways function in T‐DNA integration, and/or that integration requires some yet unknown pathway.
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This content will become publicly available on June 3, 2026
Generation of topologically defined linear and cyclic DNA bottle brush polymers via a graft-to approach
Plasmid-derived DNA bottlebrush polymers with linear and circular topologies are synthesizedviaaqueous grafting of PEG. These constructs exhibit tunable mechanics, enhanced nuclease resistance, and preserve DNA structure and circularity.
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- Award ID(s):
- 2340569
- PAR ID:
- 10651571
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 16
- Issue:
- 22
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 2646 to 2658
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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