Proteomic and Transcriptomic Analyses of Fecundity in the Brown Planthopper Nilaparvata lugens (Stål)

Abstract

As an r-strategy insect species, the brown planthopper (BPH) Nilaparvata lugens (Stål) is a serious pest of rice crops in the temperate and tropical regions of Asia and Australia, which may be due to its robust fecundity. Here we combined 2-DE comparative proteomic and RNA-seq transcriptomic analyses to identify fecundity-related proteins and genes. Using high- and low-fecundity populations as sample groups, a total of 54 and 75 proteins were significantly altered in the third and sixth day brachypterous female stages, respectively, and 39 and 54 of these proteins were identified by MALDI-TOF/TOF MS. In addition, 71,966 unigenes were quantified by Illumina sequencing. On the basis of the transcriptomic analysis, 7408 and 1639 unigenes demonstrated higher expression levels in the high-fecundity population in the second day brachypterous female adults and the second day fifth instar nymphs, respectively, and 411 unigenes were up-regulated in both groups. Of these dozens of proteins and thousands of unigenes, five were differentially expressed at both the protein and mRNA levels at all four time points, suggesting that these genes may regulate fecundity. Glutamine synthetase (GS) was chosen for further functional studies. RNAi knockdown of the GS gene reduced the fecundity of N. lugens by 64.6%, disrupted ovary development, and inhibited vitellogenin (Vg) expression. Our results show that a combination of proteomic and transcriptomic analyses provided five candidate proteins and genes for further study. The knowledge gained from this study may lead to a more fundamental understanding of the fecundity of this important agricultural insect pest.

Genome sequence of a rice pest, the white-backed planthopper (Sogatella furcifera)

“…More importantly, the planthopper transmits devastating rice viruses, including the Southern rice black-streaked dwarf virus (SRBSDV), which poses an additional threat to rice plants [3]. Insecticide misuse, cultivation of hybrid high-nutritional rice varieties, cultural and climatic factors, long-distance migration capability and robust fecundity of S. furcifera , together result in outbreaks of S. furcifera [2, 4]. …”

Identification and Validation of Reference Genes for Quantitative Real-Time PCR in Drosophila suzukii (Diptera: Drosophilidae)

“…So far, several housekeeping genes, such as ribosomal protein L18 ( RPL18 ) [8], ribosomal protein S3 ( RPS3 ) [9], arginine kinase ( AK ) [10], elongation factor 1 beta ( EF-1β ) [11], TATA binding protein ( TBP ) [12], NADH dehydrogenase ( NADH ), heat shock protein 22 ( HSP22 ) [13], glyceraldehyde-3-phosphate dehydrogenase ( GAPDH ) [14], Actin [15] and α-Tubulin [16], [17] have been used widely as reference genes for qRT-PCR analysis in Insecta and other species. However, based on previous studies, it will not have a single universal reference gene that is suited for all experimental conditions [18]–[20].…”

Application of Virus-Derived Small Interfering RNAs (vsiRNAs) in Rice Viruses with Insect Vectors, Especially <em>Rice Grassy Stunt Virus</em>

“…DCR-2 gene disclosed 55% minimization of gene expression in N. lugens after feeding, and also no changes were seen insect development [126]. Glutamate synthase (GS) knockdown by RNAi also decreased the fecundity of N. lugens by almost 64.6%, disrupted ovary development and showed vitellogenin (Vg) inhibition [117]. DCR plays an important role in N. lugens for the regulation of oogenesis in the telotrophic ovary [125].…”