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Merchant A, Zhou X. Caste-biased patterns of brain investment in the subterranean termite Reticulitermes flavipes. iScience 2024; 27:110052. [PMID: 38883809 PMCID: PMC11176635 DOI: 10.1016/j.isci.2024.110052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 03/04/2024] [Accepted: 05/17/2024] [Indexed: 06/18/2024] Open
Abstract
Investment into neural tissue is expected to reflect the specific sensory and behavioral capabilities of a particular organism. Termites are eusocial insects that exhibit a caste system in which individuals can develop into one of several morphologically and behaviorally distinct castes. However, it is unclear to what extent these differences between castes are reflected in the anatomy of the brain. To address this question, we used deformation-based morphometry to conduct pairwise comparisons between the brains of different castes in the eastern subterranean termite, Reticulitermes flavipes. Workers exhibited enlargement in the antennal lobes and mushroom bodies, while reproductives showed increased investment into the optic lobes and central body. In addition, caste-specific enlargement was observed in regions that could not be mapped to distinct neuropils, most notably in soldiers. These findings demonstrate a significant influence of caste development on brain anatomy in termites alongside convergence with eusocial hymenopteran systems.
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Affiliation(s)
- Austin Merchant
- Department of Entomology, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Xuguo Zhou
- Department of Entomology, School of Integrative Biology, College of Liberal Arts & Sciences, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
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Du H, Huang R, Chen DS, Zhuang T, Huang X, Zhang H, Li Z. Regulation of soldier caste differentiation by microRNAs in Formosan subterranean termite ( Coptotermes formosanus Shiraki). PeerJ 2024; 12:e16843. [PMID: 38436016 PMCID: PMC10909360 DOI: 10.7717/peerj.16843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 01/05/2024] [Indexed: 03/05/2024] Open
Abstract
The soldier caste is one of the most distinguished castes inside the termite colony. The mechanism of soldier caste differentiation has mainly been studied at the transcriptional level, but the function of microRNAs (miRNAs) in soldier caste differentiation is seldom studied. In this study, the workers of Coptotermes formosanus Shiraki were treated with methoprene, a juvenile hormone analog which can induce workers to transform into soldiers. The miRNomes of the methoprene-treated workers and the controls were sequenced. Then, the differentially expressed miRNAs (DEmiRs) were corrected with the differentially expressed genes DEGs to construct the DEmiR-DEG regulatory network. Afterwards, the DEmiR-regulated DEGs were subjected to GO enrichment and KEGG enrichment analysis. A total of 1,324 miRNAs were identified, among which 116 miRNAs were screened as DEmiRs between the methoprene-treated group and the control group. A total of 4,433 DEmiR-DEG pairs were obtained. No GO term was recognized as significant in the cellular component, molecular function, or biological process categories. The KEGG enrichment analysis of the DEmiR-regulated DEGs showed that the ribosome biogenesis in eukaryotes and circadian rhythm-fly pathways were enriched. This study demonstrates that DEmiRs and DEGs form a complex network regulating soldier caste differentiation in termites.
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Affiliation(s)
- He Du
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Runmei Huang
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Da-Song Chen
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Tianyong Zhuang
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Xueyi Huang
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Huan Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Zhiqiang Li
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
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Chen J, Setia G, Lin LH, Sun Q, Husseneder C. Weight and protozoa number but not bacteria diversity are associated with successful pair formation of dealates in the Formosan subterranean termite, Coptotermes formosanus. PLoS One 2023; 18:e0293813. [PMID: 37956140 PMCID: PMC10642788 DOI: 10.1371/journal.pone.0293813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 10/19/2023] [Indexed: 11/15/2023] Open
Abstract
New colonies of Formosan subterranean termites are founded by monogamous pairs. During swarming season, alates (winged reproductives) leave their parental colony. After swarming, they drop to the ground, shed their wings, and male and female dealates find suitable nesting sites where they mate and become kings and queens of new colonies. The first generation of offspring is entirely dependent on the nutritional resources of the founder pair consisting of the fat and protein reserves of the dealates and their microbiota, which include the cellulose-digesting protozoa and diverse bacteria. Since termite kings and queens can live for decades, mate for life and colony success is linked to those initial resources, we hypothesized that gut microbiota of founders affect pair formation. To test this hypothesis, we collected pairs found in nest chambers and single male and female dealates from four swarm populations. The association of three factors (pairing status, sex of the dealates and population) with dealate weights, total protozoa, and protozoa Pseudotrichonympha grassii numbers in dealate hindguts was determined. In addition, Illumina 16S rRNA gene sequencing and the QIIME2 pipeline were used to determine the impact of those three factors on gut bacteria diversity of dealates. Here we report that pairing status was significantly affected by weight and total protozoa numbers, but not by P. grassii numbers and bacteria diversity. Weight and total protozoa numbers were higher in paired compared to single dealates. Males contained significantly higher P. grassii numbers and bacteria richness and marginally higher phylogenetic diversity despite having lower weights than females. In conclusion, this study showed that dealates with high body weight and protozoa numbers are more likely to pair and become colony founders, probably because of competitive advantage. The combined nutritional resources provided by body weight and protozoa symbionts of the parents are important for successful colony foundation and development.
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Affiliation(s)
- Junyan Chen
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, Los Angeles, United States of America
| | - Garima Setia
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, Los Angeles, United States of America
| | - Li-Hsiang Lin
- Department of Experimental Statistics, Louisiana State University Agricultural Center, Baton Rouge, Los Angeles, United States of America
| | - Qian Sun
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, Los Angeles, United States of America
| | - Claudia Husseneder
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, Los Angeles, United States of America
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Takata M, Yabe K, Noro T, Mizote S, Konishi T, Tasaki E, Matsuura K. A method for estimating colony size using queen fecundity in termites under field conditions. THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 2023; 110:35. [PMID: 37458826 DOI: 10.1007/s00114-023-01865-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/05/2023] [Accepted: 07/07/2023] [Indexed: 07/20/2023]
Abstract
Colony size in social insects is one of the most important factors in shaping their self-organized system. It affects a wide variety of traits such as foraging and defense strategies, social immune responses, the degree of polymorphism, and reproductive output. However, colony size estimation of subterranean termites in the field has been challenging, due to their extremely cryptic biology and multiple site-nesting behavior. Since natural selection favors workers that maximize the number of their siblings, the amount of egg production may reflect the number of workers in the colony. Here, we report a method for inferring colony size in the field using total egg production in each colony from a subterranean termite, Reticulitermes speratus. Our investigation of field colonies revealed that the body weight of queens reaches a peak and had the largest variance in June and July and accurately predicts the number of eggs laid by the queen per 24 h. Using laboratory-reared colonies, we found that the total egg production in each colony is proportional to the number of workers. We also estimated the colony size of 198 field colonies and found that the median and maximum colony size was 24,500 and 451,800 workers per colony. The method for inferring colony size presented here may also be applicable to termite species with a clear seasonality in egg production. The colony size estimate will contribute to understanding the life history strategies and social systems of termites.
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Affiliation(s)
- Mamoru Takata
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan.
| | - Kiyotaka Yabe
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Takuya Noro
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Shun Mizote
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Takao Konishi
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Eisuke Tasaki
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
- Present address: Department of Biology, Faculty of Science, Niigata University, 8050 Ikarashi 2-no-cho, Nishi-ku, Niigata, 950-2181, Japan
| | - Kenji Matsuura
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
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Su NY, Mullins A, Chouvenc T. Elimination of structural and tree infestations of the Asian subterranean termite, Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae) with noviflumuron baits in above-ground stations. JOURNAL OF ECONOMIC ENTOMOLOGY 2023:7157081. [PMID: 37156234 DOI: 10.1093/jee/toad077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/07/2023] [Accepted: 04/21/2023] [Indexed: 05/10/2023]
Abstract
The traditional stake survey and in-ground (IG) monitoring stations have been ineffective in aggregating the Asian subterranean termite, Coptotermes gestroi (Wasmann) in southeastern Florida. In this study, we used both IG and above-ground (AG) Sentricon stations to monitor and bait C. gestroi, and as expected, none of the 83 IG stations was intercepted. Despite this, AG bait stations with 0.5% noviflumuron were successfully used to eliminate C. gestroi colonies. From 2 field experiments, the mean colony elimination time (±SD) using AG baits were 6.4 ± 3.8 wk (n = 4) and 8.0 ± 2.1 wk (n = 12), respectively. Such results were compatible with baiting studies against field colonies of C. gestroi elsewhere, that is, 4-9 wk. The successful rates in monitoring and baiting of C. gestroi with IG stations in other regions also varied, which may be due to the variabilities in tunnel geometry of this species in different environments. In areas with established C. gestroi populations, routine inspection for signs of activity in structures and surrounding trees can be a critical component for pest control providers for early detection of infestation and colony elimination with AG bait stations.
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Affiliation(s)
- Nan-Yao Su
- Entomology and Nematology Department, Ft. Lauderdale Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences, 3205 College Ave., Ft. Lauderdale, FL 33314, USA
| | - Aaron Mullins
- Entomology and Nematology Department, Ft. Lauderdale Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences, 3205 College Ave., Ft. Lauderdale, FL 33314, USA
| | - Thomas Chouvenc
- Entomology and Nematology Department, Ft. Lauderdale Research and Education Center, University of Florida, Institute of Food and Agricultural Sciences, 3205 College Ave., Ft. Lauderdale, FL 33314, USA
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Chouvenc T. Eusociality and the transition from biparental to alloparental care in termites. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Thomas Chouvenc
- Entomology and Nematology Department, Ft Lauderdale Research and Education Center University of Florida Institute of Food and Agricultural Sciences, 3205 College Ave, Ft Lauderdale, FL 33314 USA
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