Adipokinetic hormone signaling regulates cytochrome P450-mediated chlorantraniliprole sensitivity in Spodoptera frugiperda (Lepidoptera: Noctuidae).

BACKGROUND: Fall armyworm (FAW, Spodoptera frugiperda) is one of the most destructive and invasive pests worldwide and causes significant economic losses. Intensive and frequent use of insecticides has led to the development of resistance in FAW. Adipokinetic hormone (AKH) have been proven to be involved in insecticide resistance in insects. However, the molecular mechanism underlying chlorantraniliprole resistance mediated by AKH signaling in FAW remains unclear. RESULTS: The expression of SpfAKHR was highest in male adults and lowest in 1st instar larvae. SpfAKH was expressed the highest in eggs and the lowest in 6th instar larvae. AKH signaling was involved in the sensitivity of FAW to chlorantraniliprole through a toxicological bioassay, and the combination of chlorantraniliprole and bithionol (an inhibitor of key enzymes in the AKH pathway) significantly increased the mortality of FAW. Chlorantraniliprole significantly induced the expression of ten P450s, SpfAKH and SpfAKHR in FAW. RNA interference against SpfAKHR significantly decreased the P450 content, downregulated the expression of three P450 genes (SpfCYP6B50, SpfCYP321A9 and SpfCYP9A58) and inhibited the resistance of FAW to chlorantraniliprole. The topical application of AKH peptide significantly increased the P450 content, upregulated the expression of five P450 genes (SpfCYP321A9, SpfCY321A8, SpfCYP321A10, SpfCYP321A7 and SpfCYP6AB12), and enhanced the survival of FAW against chlorantraniliprole. CONCLUSIONS: AKH plays an important role in enhancing chlorantraniliprole resistance in FAW by exerting a positive influence on P450 gene expression and P450 content. These results provide valuable insights into insecticide resistance regulation and FAW control strategies. © 2022 Society of Chemical Industry.

Progress on genome-wide CRISPR/Cas9 screening for functional genes and regulatory elements.

The CRISPR/Cas9 system is a powerful tool which has been extensively used for genome editing in the past few years. Nuclease-dead Cas9 (CRISPR/dCas9), a Cas9 protein mutant without splicing ability, along with loss-of- function (LOF), gain-of-function (GOF), or non-coding genes scanning approaches can reveal genome-scale functional determinants. CRISPR/Cas9 has been widely adopted to decipher disease mechanisms and pinpoint drug targets in the life science field, and also provide novel insights into animal genetics and breeding. In this review, we summarize the research progress in high-throughput CRISPR/Cas9 screening for revealing the functional genes and regulatory elements in the whole genome. We also highlight the applications of CRISPR/Cas9 system in the animal cells, providing a reference for gene editing and other related research in related fields.

The sodium channel gene family is specifically expressed in hen uterus and associated with eggshell quality traits.

BACKGROUND: Eggshell quality is important for the poultry industry. During eggshell formation a mass of inorganic minerals is deposited. The Sodium Channel (SCNN1) gene family plays an essential role in cation transportation. The objective of this study was to investigate the pattern of expression of members of the SCNN1 gene family, their variation and their effects on eggshell quality. RESULT: The highest expression of SCNN1a, SCNN1b, and SCNN1g genes were in the active uterus during eggshell mineralization, while SCNN1d showed its highest expression level in the quiescent uterus (no egg present). Nineteen candidate SNPs from the four genes were genotyped in a population of 338 White Leghorn layers. Association analysis between SNPs (haplotypes/diplotypes) and eggshell traits was performed. Among seven significant SNPs, five SNPs were associated with eggshell strength, eggshell thickness, eggshell percentage or/and egg weight, while the other two SNPs within SCNN1d were only associated with eggshell percentage. These SNPs had a 0.25-6.99% contribution to phenotypic variance, depending on the trait. In haplotype analysis, SCNN1b and SCNN1d were associated with egg weight. The SCNN1b and SCNN1g were significantly associated with eggshell weight while only SCNN1g explained 2.04% of phenotypic variance. All the alleles of the members of SCNN1 gene family were associated with eggshell percentage and eggshell thickness, and others members had an association with eggshell strength except for SCNN1a. The contribution of different haplotypes of the SCNN1 gene family to eggshell phenotypic variance ranged from 0.09% to 5.74%. CONCLUSIONS: Our study indicated that the SCNN1 gene family showed tissue expression specificity and was significantly associated with eggshell traits in chicken. This study provides evidence that genetic variation in members of the sodium channel can influence eggshell quality.