Few chemoreceptor genes in the ambrosia beetle Trypodendron lineatum may reflect its specialized ecology
Biswas, Twinkle LU
; Vogel, Heiko
; Biedermann, Peter H. W.
; Lehenberger, Maximilian
; Yuvaraj, Jothi Kumar
LU
and Andersson, Martin N
LU
(2024)
In BMC Genomics
25.
- Abstract
- Background
Chemoreception is crucial for insect fitness, underlying for instance food-, host-, and mate finding. Chemicals in the environment are detected by receptors from three divergent gene families: odorant receptors (ORs), gustatory receptors (GRs), and ionotropic receptors (IRs). However, how the chemoreceptor gene families evolve in parallel with ecological specializations remains poorly understood, especially in the order Coleoptera. Hence, we sequenced the genome and annotated the chemoreceptor genes of the specialised ambrosia beetle Trypodendron lineatum (Coleoptera, Curculionidae, Scolytinae) and compared its chemoreceptor gene repertoires with those of other scolytines with different ecological adaptations, as well... (More) - Background
Chemoreception is crucial for insect fitness, underlying for instance food-, host-, and mate finding. Chemicals in the environment are detected by receptors from three divergent gene families: odorant receptors (ORs), gustatory receptors (GRs), and ionotropic receptors (IRs). However, how the chemoreceptor gene families evolve in parallel with ecological specializations remains poorly understood, especially in the order Coleoptera. Hence, we sequenced the genome and annotated the chemoreceptor genes of the specialised ambrosia beetle Trypodendron lineatum (Coleoptera, Curculionidae, Scolytinae) and compared its chemoreceptor gene repertoires with those of other scolytines with different ecological adaptations, as well as a polyphagous cerambycid species.
Results
We identified 67 ORs, 38 GRs, and 44 IRs in T. lineatum (‘Tlin’). Across gene families, T. lineatum has fewer chemoreceptors compared to related scolytines, the coffee berry borer Hypothenemus hampei and the mountain pine beetle Dendroctonus ponderosae, and clearly fewer receptors than the polyphagous cerambycid Anoplophora glabripennis. The comparatively low number of chemoreceptors is largely explained by the scarcity of large receptor lineage radiations, especially among the bitter taste GRs and the ‘divergent’ IRs, and the absence of alternatively spliced GR genes. Only one non-fructose sugar receptor was found, suggesting several sugar receptors have been lost. Also, we found no orthologue in the ‘GR215 clade’, which is widely conserved across Coleoptera. Two TlinORs are orthologous to ORs that are functionally conserved across curculionids, responding to 2-phenylethanol (2-PE) and green leaf volatiles (GLVs), respectively.
Conclusions
Trypodendron lineatum reproduces inside the xylem of decaying conifers where it feeds on its obligate fungal mutualist Phialophoropsis ferruginea. Like previous studies, our results suggest that stenophagy correlates with small chemoreceptor numbers in wood-boring beetles; indeed, the few GRs may be due to its restricted fungal diet. The presence of TlinORs orthologous to those detecting 2-PE and GLVs in other species suggests these compounds are important for T. lineatum. Future functional studies should test this prediction, and chemoreceptor annotations should be conducted on additional ambrosia beetle species to investigate whether few chemoreceptors is a general trait in this specialized group of beetles.
(Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/ab654b2c-1564-41ed-86f2-127ad75117d9
- author
- Biswas, Twinkle
LU
; Vogel, Heiko
; Biedermann, Peter H. W.
; Lehenberger, Maximilian
; Yuvaraj, Jothi Kumar
LU
and Andersson, Martin N
LU
- organization
- publishing date
- 2024-08-06
- type
- Contribution to journal
- publication status
- published
- subject
- in
- BMC Genomics
- volume
- 25
- article number
- 764
- publisher
- BioMed Central (BMC)
- external identifiers
-
- pmid:39107741
- scopus:85200477476
- ISSN
- 1471-2164
- DOI
- 10.1186/s12864-024-10678-4
- language
- English
- LU publication?
- yes
- id
- ab654b2c-1564-41ed-86f2-127ad75117d9
- date added to LUP
- 2024-08-21 12:37:26
- date last changed
- 2024-08-30 13:15:45
@article{ab654b2c-1564-41ed-86f2-127ad75117d9,
abstract = {{Background<br/><br/>Chemoreception is crucial for insect fitness, underlying for instance food-, host-, and mate finding. Chemicals in the environment are detected by receptors from three divergent gene families: odorant receptors (ORs), gustatory receptors (GRs), and ionotropic receptors (IRs). However, how the chemoreceptor gene families evolve in parallel with ecological specializations remains poorly understood, especially in the order Coleoptera. Hence, we sequenced the genome and annotated the chemoreceptor genes of the specialised ambrosia beetle Trypodendron lineatum (Coleoptera, Curculionidae, Scolytinae) and compared its chemoreceptor gene repertoires with those of other scolytines with different ecological adaptations, as well as a polyphagous cerambycid species.<br/><br/>Results<br/><br/>We identified 67 ORs, 38 GRs, and 44 IRs in T. lineatum (‘Tlin’). Across gene families, T. lineatum has fewer chemoreceptors compared to related scolytines, the coffee berry borer Hypothenemus hampei and the mountain pine beetle Dendroctonus ponderosae, and clearly fewer receptors than the polyphagous cerambycid Anoplophora glabripennis. The comparatively low number of chemoreceptors is largely explained by the scarcity of large receptor lineage radiations, especially among the bitter taste GRs and the ‘divergent’ IRs, and the absence of alternatively spliced GR genes. Only one non-fructose sugar receptor was found, suggesting several sugar receptors have been lost. Also, we found no orthologue in the ‘GR215 clade’, which is widely conserved across Coleoptera. Two TlinORs are orthologous to ORs that are functionally conserved across curculionids, responding to 2-phenylethanol (2-PE) and green leaf volatiles (GLVs), respectively.<br/><br/>Conclusions<br/><br/>Trypodendron lineatum reproduces inside the xylem of decaying conifers where it feeds on its obligate fungal mutualist Phialophoropsis ferruginea. Like previous studies, our results suggest that stenophagy correlates with small chemoreceptor numbers in wood-boring beetles; indeed, the few GRs may be due to its restricted fungal diet. The presence of TlinORs orthologous to those detecting 2-PE and GLVs in other species suggests these compounds are important for T. lineatum. Future functional studies should test this prediction, and chemoreceptor annotations should be conducted on additional ambrosia beetle species to investigate whether few chemoreceptors is a general trait in this specialized group of beetles.<br/>}},
author = {{Biswas, Twinkle and Vogel, Heiko and Biedermann, Peter H. W. and Lehenberger, Maximilian and Yuvaraj, Jothi Kumar and Andersson, Martin N}},
issn = {{1471-2164}},
language = {{eng}},
month = {{08}},
publisher = {{BioMed Central (BMC)}},
series = {{BMC Genomics}},
title = {{Few chemoreceptor genes in the ambrosia beetle Trypodendron lineatum may reflect its specialized ecology}},
url = {{http://dx.doi.org/10.1186/s12864-024-10678-4}},
doi = {{10.1186/s12864-024-10678-4}},
volume = {{25}},
year = {{2024}},
}