Data from: Requirement of group I lytic polysaccharide monooxygenase for turnover of chitinous cuticle during molting in two forest pest beetles, Monochamus alternatus and Psacothea hilaris

Kim, Daehyeong1; Muthukrishnan, Subbaratnam2; Kramer, Karl J.2; Arakane, Yasuyuki1 ; Noh, Mi Young 1

Published Sep 15, 2025 on Dryad. https://doi.org/10.5061/dryad.bk3j9kdqz

Data files

Sep 15, 2025 version files 49.05 KB

Data_file_1.xlsx

15.35 KB
Data_file_2.xlsx

13.97 KB
Data_file_3.xlsx

15.20 KB
README.md

4.53 KB

Abstract

Lytic polysaccharide monooxygenases (LPMOs) that are capable of oxidative cleavage of glycosidic bonds in crystalline polysaccharides including chitin and cellulose are widely distributed among organisms. Insect LPMOs belong to auxiliary activity family 15 (LPMO15/AA15) and have been classified further into at least four subgroups. However, unlike LPMOs from microorganisms and viruses, their physiological functions in insects have not been well studied. In the present work, we investigated the functions of two group I LPMO15s, MaLPMO15-1 and PhLPMO15-1, in chitinous cuticle turnover during molting of two important forest pest longhorn beetles, the Japanese pine sawyer beetle, Monochamus alternatus, and the yellow spotted longicorn beetle, Psacothea hilaris. Real-time qPCR showed a similar pattern of expression of MaLPMO15-1 and PhLPMO15-1 during late stages of development with high levels present at young pharate pupal and young pupal stages and declining thereafter. Injection of double-stranded RNA (dsRNA) for MaLPMO15-1 (dsMaLPMO15-1) or PhLPMO15-1 (dsPhLPMO15-1) into last instar larvae of M. alternates and P. hilaris, respectively, did not affect subsequent larval-pupal molting and the resulting pupae exhibited normal development. However, the pupae were unable to eclose to the adult stage and died entrapped inside their old pupal cuticle. TEM analysis revealed that, unlike the respective dsEGFP-treated control insects, both dsMaLPMO15-1- and dsPhLPMO15-1-treated pharate adults failed to degrade the endocuticular layer of their pupal cuticle in which the horizontal chitinous laminae remained largely intact. These results demonstrate that the group I LPMO15-1 enzymes play a role in pupal cuticle chitin turnover, which is critical for molting to the adult. Because LPMO15-1 is highly conserved among many insect species, this gene/enzyme is a potential target for the control of populations of both M. alternatus and P. hilaris as well as other pest insect species.

Dataset DOI: 10.5061/dryad.bk3j9kdqz

Description of the data and file structure

Data files: Requirement of Group I lytic polysaccharide monooxygenase for turnover of chitinous cuticle during molting in two forest pest beetles, Monochamus alternatus and Psacothea hilaris

We have submitted our raw data for the real-time qPCR analysis (Data_file_1.xlsx and Data_file_2.xlsx) and cuticle thickness measurement in MaLPMO15-1- and PhLPMO15-1-deficient pharate adults (Data_file_3.xlsx).

Files and variables

File: Data_file_1.xlsx

Description: Low data of real-time qPCR for analysis of expression profiles of MaLPMO15-1 and PhLPMO15-1 during late stages of development (Figure 3a and b).

Column A: Gene; MaLPMO15-1 and PhLPMO15-1 genes analyzed.
Column B: Stage; late stages of development analyzed. YPP, young pharate pupae; OPP, old pharate pupae; P0-P14, 0-14 d-old pupae; A1, 1 d-old adults; A5, 5 d-old adults.
Columns C-F: Samples 1-4; total RNA was isolated from pools of three whole insects collected ranging from young pharate pupae (YPP) to 5 d-old adults (A5). Total RNA was independently isolated from each of four replications (Samples 1-4). The values indicate transcript levels of MaLPMO15-1 and PhLPMO15-1 relative to those of M. alternatus ribosomal protein S6 (MaRpS6) and *P. hilaris *ribosomal protein S6 (PhRpS6), respectively.
Column G: Average; value of average of the relative transcript levels of MaLPMO15-1 and PhLPMO15-1.
Column H: SEM; value of standard error of the mean.

File: Data_file_2.xlsx

Description: Low data of real-time qPCR for analysis of knockdown levels of MaLPMO15-1 and PhLPMO15-1 transcripts after RNAi (Figure 4a and b).

Column A: Figure; data are shown in figures indicated.
Column B: dsRNA; double-stranded RNA (dsRNA) used. dsEGFP, dsRNA for enhanced green flourescent protein (negative control); dsMaLPMO15-1, dsRNA for MaLPMO15-1; dsPhLPMO15-1, dsRNA for PhLPMO15-1.
Columns C-E: Samples 1-3; total RNA was isolated from three whole young pharate pupae and 1 d-old pupae that had been injected with dsMaLPMO15-1 and dsPhLPMO15-1 into last instar larvae of M. alternatus and P. hilaris, respectively. Total RNA was independently isolated from each of three replications (Samples 1-3). The values indicate expression levels of MaLPMO15-1 and PhLPMO15-1 relative to the levels in respective dsEGFP-treated controls.
Column F: Average; value of average of the relative transcript levels of MaLPMO15-1 and PhLPMO15-1.
Column G: SEM; value of standard error of the mean.
Column H: t.test; Statistical analyses were performed using the Student t-test. Significant differences (p-values) between dsEGFP-controls and dsLPMO15-1-treated insects are shown.

File: Data_file_3.xlsx

Description: Thickness measurement of newly forming adult and old pupal cuticles from dsMaLPMO15-1 and dsPhLPMO15-1-treated pharate adults (described in section 3.5).

Column A: Species; M. alternatus and P. hilaris used.
Column B: dsRNA; double-stranded RNA (dsRNA) used. dsEGFP, dsRNA for enhanced green flourescent protein (negative control); dsMaLPMO15-1, dsRNA for MaLPMO15-1; dsPhLPMO15-1, dsRNA for PhLPMO15-1.
Column C: Cuticle: old pual and newly forming adult cuticles from the pharate adults of M. alternatus and P. hilaris that had been treated with dsMaLPMO15-1 and dsPhLPMO15-1 at last instar larval stage, respectively.
Columns D-L: Samples 1-9; The values indicate thickness (µm) of the old pupal or newly forming adult cuticles. Nine cuticle specimens (Samples 1-9) for each group prepared from 3-5 dsRNA-treated pharate adults were analyzed.
Columns M: Average; Value of average of cuticle thickness (µm).
Columns N: SEM; value of standard error of the mean.
Columns O: t.test; Statistical analyses were performed using the Student t-test. Significant differences (p-values) between dsEGFP-controls and dsLPMO15-1-treated insects are shown.

Code/software

Microsoft Excel (.xlsx) software is required to view the data.