International Journal Of Bilogical Sciences
.: Home > International Journal Of Bilogical Sciences > 2016 > Volume 12 Number 11 > Ji-Feng Shi1, Li-Li Mu1, Xu Chen1, Wen-Chao Guo2, Guo-Qing Li1
RNA interference of chitin synthase genes inhibits chitin biosynthesis and affects larval performance in Leptinotarsa decemlineata (Say)
Ji-Feng Shi1, Li-Li Mu1, Xu Chen1, Wen-Chao Guo2, Guo-Qing Li1
1. Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China. 2. Department of Plant Protection, Xinjiang Academy of Agricultural Sciences; Urumqi 830091, China. Corresponding author: Guo-Qing Li, Email: email@example.com. Tel/Fax: +86-25-84395248.
Dietary introduction of bacterially expressed double-stranded RNA (dsRNA) has great potential for management of Leptinotarsa decemlineata. Identification of the most attractive candidate genes for RNA interference (RNAi) is the first step. In the present paper, three complete chitin synthase cDNA sequences (LdChSAa, LdChSAb and LdChSB) were cloned. LdChSAa and LdChSAb, two splicing variants of LdChSA gene, were highly expressed in ectodermally-derived epidermal cells forming epidermis, trachea, foregut and hindgut, whereas LdChSB was mainly transcribed in midgut cells. Feeding bacterially expressed dsChSA (derived from a common fragment of LdChSAa and LdChSAb), dsChSAa, dsChSAb and dsChSB in the second- and fourth-instar larvae specifically knocked down their target mRNAs. RNAi of LdChSAa+LdChSAb and LdChSAa lowered chitin contents in whole body and integument samples, and thinned tracheal taenidia. The resulting larvae failed to ecdyse, pupate, or emerge as adults. Comparably, knockdown of LdChSAb mainly affected pupal-adult molting. The LdChSAb RNAi pupae did not completely shed the old larval exuviae, which caused failure of adult emergence. In contrast, silencing of LdChSB significantly reduced foliage consumption, decreased chitin content in midgut sample, damaged midgut peritrophic matrix, and retarded larval growth. As a result, the development of the LdChSB RNAi hypomorphs was arrested. Our data reveal that these LdChSs are among the effective candidate genes for an RNAi-based control strategy against L. decemlineata.
Leptinotarsa decemlineata, chitin synthase, RNA interference, control
Date Deposited : 07 Nov 2016 21:06
Official URL: http://www.ijbs.com/v12i11
Last Modified : 07 Nov 2016 21:06
Volume 12, Number 11, October 2016
Full Text Original