Transgenic expression of Dendrolimus kikuchii nucleopolyhedrovirus enhancin in tobacco enhances the mortality and affects the development of Spodoptera exigua larvae

ABSTRACT

A novel 2551-bp enhancin gene designated En-Dk was isolated from the Dendrolimus kikuchii nucleopolyhedrovirus genome. Sequence analysis revealed that En-Dk encodes a polypeptide chain of 792 amino acid residues containing a conserved enhancin domain and an α-helical transmembrane domain, but no signal peptide. Compared with wild-type tobacco (Nicotiana tabacum L.), transgenic tobacco showed significant phenotypic changes following En-Dk overexpression with slower growth and delayed initial flowering. An interesting finding is that the transgenic tobacco exerted a toxic effect on newly hatched Spodoptera exigua larvae, with a significant inhibitory effect on third-instar larvae in terms of body weight, pupal weight, pupation and the emergence process.

KEYWORDS:

• Dendrolimus kikuchii nucleopolyhedrovirus
• enhancin
• transgenic tobacco
• bioactivity
• Spodoptera exigua

Supplemental material

Supplemental data for this article can be accessed online here: http://dx.doi.org/10.1080/09583157.2015.1129053

Additional information

Funding

This work was supported by the Program of National Nature Science Foundation of China [grant no. 31200491] and State 863 Project funded by Ministry of Science and Technology [grant no. 2012AA101503] P. R. China.