Plant-generated artificial small RNAs mediated aphid resistance

Area of Science:

• Plant biotechnology
• Insect resistance
• RNA interference

Background:

• RNA silencing regulates gene expression and defends against pathogens in plants.
• Transgenic plants expressing hairpin RNAs (hpRNAs) or artificial microRNAs (amiRNAs) confer resistance to viruses.
• Plant-mediated RNA silencing is a promising strategy for developing insect-resistant crops.

Purpose of the Study:

• To identify aphid genes susceptible to plant-mediated RNA silencing.
• To develop aphid-resistant transgenic tobacco plants.
• To compare the efficacy of hpRNAs and amiRNAs against aphids.

Main Methods:

• Selected nine essential genes of the aphid Myzus persicae as silencing targets.
• Constructed hpRNA-expressing vectors for target genes.
• Developed two amiRNA-expressing vectors for the acetylcholinesterase 2 gene (MpAChE2).
• Transformed vectors into tobacco plants (Nicotiana tabacum cv. Xanti).
• Performed insect challenge assays to evaluate aphid resistance.

Main Results:

• Most transgenic plants exhibited enhanced aphid resistance.
• Plants expressing hpRNAs targeting V-type proton ATPase subunit E-like (V-ATPaseE) or tubulin folding cofactor D (TBCD) showed strong aphicidal activity.
• Transgenic plants expressing amiRNAs targeting MpAChE2 demonstrated superior aphid resistance compared to those with MpAChE2-specific hpRNA.

Conclusions:

• Plant-mediated RNA silencing is effective for developing resistance against piercing-sucking insects like aphids.
• Selection of vulnerable target genes and small RNA biotype are critical for aphid control.
• Insect-specific amiRNA expression is a highly promising approach for engineering aphid-resistant plants.