Functional Analysis of Nuclear Factor Y in the Wing-Dimorphic Brown Planthopper, Nilaparvata lugens (Hemiptera: Delphacidae).

Hao-Hao Chen,Hai-Jun Xu,Yi-Lai Liu,Jin-Li Zhang,Xin-Yang Liu

doi:10.3389/fgene.2020.585320

Hao-Hao Chen, Hai-Jun Xu + Show 3 more

Open Access

https://doi.org/10.3389/fgene.2020.585320

Copy DOI

Abstract

Nuclear factor Y (NF-Y) is a heterotrimeric transcription factor with the ability to bind to a CCAAT box in nearly all eukaryotes. However, the function of NF-Y in the life-history traits of insects is unclear. Here, we identified three NF-Y subunits, NlNF-YA, NlNF-YB, and NlNF-YC, in the wing-dimorphic brown planthopper (BPH), Nilaparvata lugens. Spatio-temporal analysis indicated that NlNF-YA, NlNF-YB, and NlNF-YC distributed extensively in various body parts of fourth-instar nymphs, and were highly expressed at the egg stage. RNA interference (RNAi)-mediated silencing showed that knockdown of NlNF-YA, NlNF-YB, or NlNF-YC in third-instar nymphs significantly extended the fifth-instar duration, and decreased nymph-adult molting rate. The addition of 20-hydroxyecdysone could specifically rescue the defect in adult molting caused by NlNF-YARNAi, indicating that NlNF-Y might modulate the ecdysone signaling pathway in the BPH. In addition, NlNF-YARNAi, NlNF-YBRNAi, or NlNF-YCRNAi led to small and moderately malformed forewings and hindwings, and impaired the normal assembly of indirect flight muscles. Adult BPHs treated with NlNF-YARNAi, NlNF-YBRNAi, or NlNF-YCRNAi produced fewer eggs, and eggs laid by these BPHs had arrested embryogenesis. These findings deepen our understanding of NF-Y function in hemipteran insects.

Highlights

Nuclear transcription factor Y (NF-Y) is an evolutionarily conserved transcription factor that exists in almost all organisms, from prokaryotes to eukaryotes (Dorn et al, 1987; Laloum et al, 2013)
Exonintron construction analysis showed that the NlNF-YA, NlNFYB, and NlNF-YC open reading frames (ORFs) consist of eight, five, and eight exons, located in scaffolds 6450/1657, 3414, and 1809, respectively
A phylogenetic analysis based on Nuclear factor Y (NF-Y) homologs from 13 species showed that NlNF-YA, NlNF-YB, and NlNF-YC together with their counterparts formed three distinct clusters (Figure 1), indicating that the brown planthopper (BPH) NF-Y genes we identified were authentic NF-Y homologs

Summary

Introduction

Nuclear transcription factor Y (NF-Y) is an evolutionarily conserved transcription factor that exists in almost all organisms, from prokaryotes to eukaryotes (Dorn et al, 1987; Laloum et al, 2013). NFY exerts differential regulation on a wide variety of genes through binding to a CCAAT box, one of the most ubiquitous elements in eukaryotic promoters (Li et al, 1992; Mantovani, 1998; Suzuki et al, 2001). The deletion of the mouse NF-YA homolog causes early embryo lethality (Bhattacharya et al, 2003). Down-regulation of mouse NF-YA was found to reduce the expression of several cell cycle control genes in differentiated muscle cells, suggesting NF-YA

Methods

Results

Conclusion