Molecular cloning, expression profiling, and functional analysis of a broad-complex isoform 2/3 (Br-Z2/Z3) transcription factor in the diamondback moth, Plutella xylostella (L.).

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a widespread and destructive pest of cruciferous crops. New strategies for controlling it are needed because it is rapidly developing resistance to conventional pesticides. In insects, transcription factors (TFs) including broad-complex (Br-C) are thought to be useful for insecticide development because they are able to regulate the transcription of functional genes involved in responses to external stimuli including insecticides. In the present study, we cloned and sequenced the open reading frames (ORFs) of three BTB-ZF encoding genes from the diamondback moth deposited in the National Center for Biotechnology Information (NCBI) database under accessions MG753773, MG288674, and MG753772. The lengths of these ORFs were 1,680, 1,428, and 1,647 bp, respectively. The phylogenetic analysis based on the predicted amino acid sequences of ZF domains showed that MG753773 and MG288674 belonged to Z2/Z3 and Z7 of Br-C while MG753772 belonged to Ttk types. In the agreement, the highest expression level of MG753773 occurred during the prepupal stage, MG288674 and MG753772 were expressed during all stages and peaked in the adult and egg stages, respectively. RNA interference silencing of MG753773 in the late third instar larvae significantly decreased survival and pupation of the insects. With precocene II, transcription of MG753773 increased (4×) in the fourth instar larva 24 hr later; 48 hr later the rate of prepupation and pupation was significantly higher. These findings will contribute to the development of new regulators of the growth and development for diamondback moth control.

Anti-neuropathic Pain Mechanistic Study on A. conyzoides Essential Oil, Precocene II, Caryophyllene, or Longifolene as Single Agents and in Combination with Pregabalin.

BACKGROUND: Neuropathic pain has become a contributor to the global burden of illness. However, the currently available drugs exhibit inadequate pain relief and significant side effects. Our previous study demonstrated that the essential oil of Ageratum conyzoides exerts potent antineuropathic pain activity through opioid receptor activation. Precocene II, longifolene, and caryophyllene are the largest component of the A. conyzoides essential oil. OBJECTIVE: The objective of the study was to determine the anti-neuropathic pain activity of precocene II, longifolene, and caryophyllene as single agents and in combination with pregabalin. Possible mechanisms of action involving the opioid receptor, ATP-sensitive potassium channel, and gammaaminobutyric acid (GABA) were further investigated. METHODS: The experimental animals (male mice Swiss Webster) were divided randomly into seven groups, namely, Normal control (naïve mice), Negative control (CMC 1%), Sham (CMC 1%), Positive control (Pregabalin 0,195 mg/ 20 g BW of mice), Test I (Precocene II 21.09 mg/Kg BW), Test II (Longifolene 9.94 mg/Kg BW), and Test III (Caryophyllene 3.64 mg/Kg BW). Each group contained 3 animals. The test groups that demonstrated anti-neuropathic pain activity were further tested in combination with pregabalin, followed by mechanistic studies. The negative, positive, and test I-III groups were induced with chronic constriction injury. RESULTS: The results of the study demonstrated that caryophyllene and longifolene, but not precocene II, exerted anti-neuropathic pain activity. The caryophyllene was shown to involve in the activation of opioid receptors and ATP-sensitive potassium channels. It was also reported to increase GABA concentration in the spinal cord. We further found that longifolene exerted its action via opioid receptor activation. The combination of A. conyzoides essential oil, longifolene, or caryophyllene with pregabalin demonstrated additive anti-neuropathic pain activity. CONCLUSION: Taken together, the results of the present study suggested that the A. conyzoides essential oil and caryophyllene have the potential to be developed as novel drugs to treat neuropathic pain.