Time-Course of CYP450 Genes Expression From Dendroctonus rhizophagus (Curculionidae: Scolytinae) During Early Hours of Drilling Bark and Settling Into the Host Tree

Abstract

Dendroctonus bark beetles (Scolytinae) are one of the most important disturbance agents of coniferous forests in North and Central America. These beetles spend their lives almost entirely under the tree bark, and their survival and reproductive success depend on their ability to overcome the toxic effect of the trees’ oleoresin. The cytochromes P450 (CYPs) are associated with the detoxification process of xenobiotics, as well as other physiological processes. Different cytochromes (families 4, 6, and 9) in the Dendroctonus species have been expressed under several experimental conditions; nevertheless, the expression time-course of these genes is unknown. To explore the induction speed of CYPs , we evaluated the relative expression of the CYP6BW5 , CYP6DG1 , CYP6DJ2 , CYP9Z18 , and CYP9Z20 genes at the early hours of drilling and settling into a tree (1, 2, 4, 6, 8, 12, 18 h) both in females and males, solitary or paired, of the bark beetle Dendroctonus rhizophagus Thomas and Bright. Our findings show that the five genes were rapidly overexpressed in the early hours (1 to 6 h) in both sexes and in solitary and paired conditions, suggesting their participation in the detoxification process. Additionally, the CYPs expression shows up- and down-regulation patterns through these short times, suggesting their probable participation in other physiological processes as the biosynthesis of hormones, pheromones or compounds related to reproduction.

Evolution and functional role prediction of the CYP6DE and CYP6DJ subfamilies in Dendroctonus (Curculionidae: Scolytinae) bark beetles

“…The latter is produced from the hydrolysis of (−)- α -pinene only by Dfro-CYP6DJ(X)2-1and 2-2. These findings showed that isoforms from subgroup X are involved mainly in the detoxification process of monoterpenes, as reported in other studies ( Dai et al, 2015 ; Obregón-Molina et al, 2015 ; Sarabia et al, 2019 ; Liu and Chen, 2022 ; Torres-Banda et al, 2022 ), independently that (−)- trans -verbenol can be used by some of these species as sexual ( D. rhizophagus ) or aggregation ( D. ponderosae ) pheromone ( Borden et al, 1987 ; Cano-Ramírez et al, 2012 ) and myrtenol as a synergistic compound of other pheromones ( Rudinsky et al, 1974 ; Zhang et al, 2009 ; Liu et al, 2013 ; Sun et al, 2013 ).…”

“…Given the diversity and functional role of CYPs in bark beetles, we hypothesized that cytochromes of CYP6DE and CYP6DJ subfamilies are involved in monoterpenes hydroxylation retain their ability to transform these compounds, regardless of whether they are involved in another function or exist other CYPs with coresponsibilities of participating in terpenes detoxification. Experimental evidence supports the participation of both subfamilies in the detoxification process and pheromone biosynthesis in Dendroctonus-bark beetles (Cano-Ramírez et al, 2013;López et al, 2013;Obregón-Molina et al, 2015;Nadeau et al, 2017;Chiu et al, 2019a;Chiu et al, 2019b;Sarabia et al, 2019;Liu et al, 2022;Liu and Chen, 2022;Torres-Banda et al, 2022). Thereby, to test this hypothesis, and using available genomic and transcriptomic resources of these bark beetles, we performed a molecular docking analysis with cytochromes of CYP6DE and CYP6DJ subfamilies and some monoterpenes present in host trees: (+)-and (−)-α-pinene, (+)-and (−)-β-pinene, (+)-3-carene, β-myrcene and R-(+)-limonene.…”

Age matters: Life-stage, tissue, and sex-specific gene expression dynamics in Ips typographus (Coleoptera: Curculionidae: Scolytinae)

“…In D. armandii, sixty-four P450s were identified in different developmental stages (larvae, pupa, and adult) and validated with RT-qPCR; nineteen CYP genes were upregulated upon host feeding (Dai et al, 2015). The role of the CYP4 and CYP9 families in detoxification was also confirmed in D. rhizophagus (Cano-Ramirez et al, 2013;Sarabia et al, 2019). In D. ponderosae, three CYPs were identified as involved in monoterpene oxidation, and one CYP was implicated in aggregation.…”

“…After host feeding, 19 CYP genes of these 41 genes showed overexpression as compared to the unfed beetles (Dai et al, 2015). Dendroctonus bark beetles showed a significant, non-sex-specific change in gene expression of CYP6DG1, CYP6BW5, CYP6DJ2, CYP9Z18, and CYP9Z20 during the early hours of host feeding, implying that cytochrome families 6 and 9 were also involved in the xenobiotic response in beetles as well (Sarabia et al, 2019). In D. rhizophagus, the role of CYPs from the CYP4, CYP6, and CYP9 families in detoxification was also confirmed.…”