Functional roles of the miR1512 family in regulating soybean resistance to Heterodera glycines.

BACKGROUND: Soybean [Glycine max (L.) Merr.] is major economic crop, yet its yields are persistently eroded by soybean cyst nematode (SCN). Although several legume-specific miRNAs are known to orchestrate the soybean-SCN dialogue, the mechanisms by which they confer SCN tolerance remain largely uncharted. RESULTS: Here, we dissected the role of the miR1512 family in SCN resistance. We uncovered distinct expression patterns among its three precursors and four mature isoforms. Overexpression of the precursors of miR1512 (MIR1512) in transgenic soybean hairy roots elevated precursor transcripts approximately 10- to 12-fold relative to empty-vector (EV) controls and reduced SCN infestation by approximately 25-35%; conversely, silencing these precursors had no impact on nematode loads. Exogenous seed coating with synthetic ds-miR1512 mature strands accelerated germination, promoted radicle elongation, and enhanced seedling biomass accumulation. Bioinformatic analyses further identified VLN3 (Glyma.10G099200), UPL1 (Glyma.05G133100), and SPL2 (Glyma.18G149800) as putative SCN-responsive targets of the miR1512 family. These genes are predicted to be suppressed by miR1512 during the early stages of infection, then re-activated between 10- and 15-days post-inoculation. CONCLUSION: Our results establish a functional framework for miR1512 and its targets in modulating soybean SCN resistance and provide an experimental basis for future nematode-resistant breeding and exogenous dsRNA applications. © 2026 Society of Chemical Industry.