# De Novo Transcriptome Profiling of Mustard Aphid (Lipaphis erysimi) and Differential Expression of Transcripts Associated with Feeding and Non-Feeding Conditions and Developmental Stages

## TL;DR

This study analyzes the transcriptome of the mustard aphid to identify genes involved in feeding and development, which could help in developing RNAi-based pest control strategies.

## Contribution

The study provides a de novo transcriptome and identifies differentially expressed genes linked to feeding and developmental stages in L. erysimi.

## Key findings

- Differential expression of 1502 transcripts was observed between feeding and non-feeding adults.
- 906 transcripts showed expression differences between nymphs and adults.
- Important transcripts related to detoxification, feeding, and development were identified for RNAi-based pest control.

## Abstract

Aphids are phloem feeders and are one of the most destructive pests of crop plants. Lipaphis erysimi is a specialist aphid that infests members of the Brassicaceae family and has detrimental impacts on the yield of oilseed and vegetable Brassicas in the Indian subcontinent. Recognising the critical need for developing aphid control strategies, we aimed to enhance the pool of gene targets for RNAi for developing resistance in Brassica crop plants against L. erysimi infestation. To understand the variations in expression profiles of genes while the aphid is feeding upon the host plant, as well as between two developmental stages (adults and nymphs), we conducted a two-way transcriptome-based differential expression analysis between feeding and non-feeding adults and between adults and nymphs. This led to the identification of important transcripts involved in detoxification, feeding, metabolism and aphid development. Our study provides valuable insights into the molecular mechanisms underlying feeding and development in aphids. It also generated an important resource for further research on aphid biology and for developing effective RNAi-based strategies for pest management and control.

Lipaphis erysimi is a specialist aphid of the Indian subcontinent that causes significant yield losses in oilseed Brassicas. Several aphid genes have been used as preferred targets in RNAi-based transgenic plants for aphid resistance. In order to enhance the repertoire of potential target genes for aphid control and to identify the genes associated with aphid feeding and development, we performed a two-way comparative study of differential gene expression profiles between (i) feeding and non-feeding adults and (ii) adult and nymph developmental stages of L. erysimi. De novo RNA-seq of aphids using Illumina technology generated a final transcriptome comprising 52,652 transcripts. Potential transcripts for host selection, detoxification, salivary proteins and effectors, molecular chaperones and developmental genes were identified. Differential gene expression studies identified variations in the expression of 1502 transcripts between feeding and non-feeding adults and 906 transcripts between nymphs and adults. These data were used to identify novel target genes for RNAi-based aphid control and facilitate further studies on the molecular basis of aphid feeding and development.