Arabidopsis thaliana SKP1 interacting protein 11 (At2g02870) negatively regulates the release of green leaf volatiles

Abstract

Green leaf volatiles (GLV) are important factors in plant defense, and plant–plant and plant–insect interactions. Kelch-repeat containing F-box proteins (KFB) are plant-specific proteins, which recruit substrates for protein degradation. The present study was conducted to evaluate the role of AtSKIP11, an Arabidopsis KFB, in the expression of hydroperoxide lyase (HPL) pathway genes and the formation of products by creating transgenic Arabidopsis thaliana plants expressing the AtSKIP11 open reading frame and its antisense sequence. We found that production of C5 volatiles was greatly reduced in these transgenic plants. The production of C6 GLV was reduced by 49% in AtSKIP11 overexpressing plants, whereas the production of these compounds was increased by 12% in the AtSKIP11-antisense suppression plants. Real time quantitative polymerase chain reaction (RT-qPCR) results showed that expression of LOX2, HPL and ADH1 genes was reduced by 1.8, 1.3 and 2.5 fold, respectively, in the AtSKIP11 overexpressing plants, compared with wild-type plants. In the AtSKIP11-antisense plants, expression of LOX2 was reduced 1.2 fold, but HPL and ADH1 genes were up-regulated by 1.2 fold and 1.7 fold, respectively, over the wild-type samples. Our results suggest the involvement of AtSKIP11 in negatively regulating the HPL pathway, especially the expression of ADH1, possibly through degradation of the transcription factors.