--- _id: '13984' abstract: - lang: eng text: "Social insects fight disease using their individual immune systems and the cooperative\r\nsanitary behaviors of colony members. These social defenses are well explored against\r\nexternally-infecting pathogens, but little is known about defense strategies against\r\ninternally-infecting pathogens, such as viruses. Viruses are ubiquitous and in the last decades\r\nit has become evident that also many ant species harbor viruses. We present one of the first\r\nstudies addressing transmission dynamics and collective disease defenses against viruses in\r\nants on a mechanistic level. I successfully established an experimental ant host – viral\r\npathogen system as a model for the defense strategies used by social insects against internal\r\npathogen infections, as outlined in the third chapter. In particular, we studied how garden ants\r\n(Lasius neglectus) defend themselves and their colonies against the generalist insect virus\r\nCrPV (cricket paralysis virus). We chose microinjections of virus directly into the ants’\r\nhemolymph because it allowed us to use a defined exposure dose. Here we show that this is a\r\ngood model system, as the virus is replicating and thus infecting the host. The ants mount a\r\nclear individual immune response against the viral infection, which is characterized by a\r\nspecific siRNA pattern, namely siRNAs mapping against the viral genome with a peak of 21\r\nand 22 bp long fragments. The onset of this immune response is consistent with the timeline\r\nof viral replication that starts already within two days post injection. The disease manifests in\r\ndecreased survival over a course of two to three weeks.\r\nRegarding group living, we find that infected ants show a strong individual immune response,\r\nbut that their course of disease is little affected by nestmate presence, as described in chapter\r\nfour. Hence, we do not find social immunity in the context of viral infections in ants.\r\nNestmates, however, can contract the virus. Using Drosophila S2R+ cells in culture, we\r\nshowed that 94 % of the nestmates contract active virus within four days of social contact to\r\nan infected individual. Virus is transmitted in low doses, thus not causing disease\r\ntransmission within the colony. While virus can be transmitted during short direct contacts,\r\nwe also assume transmission from deceased ants and show that the nestmates’ immune\r\nsystem gets activated after contracting a low viral dose. We find considerable potential for\r\nindirect transmission via the nest space. Virus is shed to the nest, where it stays viable for one\r\nweek and is also picked up by other ants. Apart from that, we want to underline the potential\r\nof ant poison as antiviral agent. We determined that ant poison successfully inactivates CrPV\r\nin vitro. However, we found no evidence for effective poison use to sanitize the nest space.\r\nOn the other hand, local application of ant poison by oral poison uptake, which is part of the\r\nants prophylactic behavioral repertoire, probably contributes to keeping the gut of each\r\nindividual sanitized. We hypothesize that oral poison uptake might be the reason why we did\r\nnot find viable virus in the trophallactic fluid.\r\nThe fifth chapter encompasses preliminary data on potential social immunization. However,\r\nour experiments do not confirm an actual survival benefit for the nestmates upon pathogen\r\nchallenge under the given experimental settings. Nevertheless, we do not want to rule out the\r\npossibility for nestmate immunization, but rather emphasize that considering different\r\nexperimental timelines and viral doses would provide a multitude of options for follow-up\r\nexperiments.\r\nIn conclusion, we find that prophylactic individual behaviors, such as oral poison uptake,\r\nmight play a role in preventing viral disease transmission. Compared to colony defense\r\nagainst external pathogens, internal pathogen infections require a stronger component of\r\nindividual physiological immunity than behavioral social immunity, yet could still lead to\r\ncollective protection." acknowledged_ssus: - _id: LifeSc alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Anna full_name: Franschitz, Anna id: 480826C8-F248-11E8-B48F-1D18A9856A87 last_name: Franschitz citation: ama: Franschitz A. Individual and social immunity against viral infections in ants. 2023. doi:10.15479/at:ista:13984 apa: Franschitz, A. (2023). Individual and social immunity against viral infections in ants. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:13984 chicago: Franschitz, Anna. “Individual and Social Immunity against Viral Infections in Ants.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:13984. ieee: A. Franschitz, “Individual and social immunity against viral infections in ants,” Institute of Science and Technology Austria, 2023. ista: Franschitz A. 2023. Individual and social immunity against viral infections in ants. Institute of Science and Technology Austria. mla: Franschitz, Anna. Individual and Social Immunity against Viral Infections in Ants. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:13984. short: A. Franschitz, Individual and Social Immunity against Viral Infections in Ants, Institute of Science and Technology Austria, 2023. date_created: 2023-08-08T15:33:29Z date_published: 2023-08-08T00:00:00Z date_updated: 2024-03-01T15:25:17Z day: '08' ddc: - '570' - '577' degree_awarded: PhD department: - _id: GradSch - _id: SyCr doi: 10.15479/at:ista:13984 file: - access_level: closed checksum: 27220243d5d51c3b0d7d61c0879d7a0c content_type: application/pdf creator: afransch date_created: 2023-08-08T18:01:28Z date_updated: 2024-03-01T08:51:42Z embargo: 2024-08-08 embargo_to: open_access file_id: '13986' file_name: Thesis_AnnaFranschitz_202308.pdf file_size: 10797612 relation: main_file - access_level: closed checksum: 40abf7ccca14a3893f72dc7fb88585d6 content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: afransch date_created: 2023-08-08T18:02:25Z date_updated: 2023-08-09T07:25:27Z file_id: '13987' file_name: Thesis_AnnaFranschitz_202308.docx file_size: 2619085 relation: source_file - access_level: closed checksum: 8b991ecc2d59d045cc3cf0d676785ec7 content_type: application/pdf creator: cchlebak date_created: 2024-03-01T08:37:15Z date_updated: 2024-03-01T12:13:29Z description: Minor modifications and clarifications - Feb 2024 embargo: 2024-08-08 embargo_to: open_access file_id: '15042' file_name: Addendum_AnnaFranschitz202402.pdf file_size: 85956 relation: erratum title: Addendum - access_level: closed checksum: 66745aa01f960f17472c024875c049ed content_type: application/vnd.openxmlformats-officedocument.wordprocessingml.document creator: cchlebak date_created: 2024-03-01T08:39:20Z date_updated: 2024-03-01T08:51:42Z file_id: '15043' file_name: Addendum_AnnaFranschitz202402.docx file_size: 11818 relation: source_file title: Addendum - source file - access_level: closed checksum: 55c876b73d49db15228a7f571592ec77 content_type: application/pdf creator: cchlebak date_created: 2024-03-01T08:56:06Z date_updated: 2024-03-01T12:58:14Z description: For printing purposes file_id: '15044' file_name: Print_Version_Franschitz_Anna_Thesis.pdf file_size: 10416761 relation: other title: Print Version file_date_updated: 2024-03-01T12:58:14Z has_accepted_license: '1' language: - iso: eng month: '08' oa_version: Published Version page: '89' publication_identifier: isbn: - 978-3-99078-034-3 issn: - 2663 - 337X publication_status: published publisher: Institute of Science and Technology Austria status: public supervisor: - first_name: Sylvia full_name: Cremer, Sylvia id: 2F64EC8C-F248-11E8-B48F-1D18A9856A87 last_name: Cremer orcid: 0000-0002-2193-3868 title: Individual and social immunity against viral infections in ants type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '2023' ... --- _id: '695' abstract: - lang: eng text: It has been known since Stefan Vogel's observations in 1969 that solitary female oil bees collect fatty floral oils from specialized oil-secreting plants with the aid of hairy patches on either their legs or abdomen, a reward used as food for their larvae and/or to line their brood cells. Similar adaptations are also known from male oil bees, although the purpose of their oil-collecting behavior has not yet been clarified. Here, we describe a novel pollination system involving male Paratetrapedia oil bees and the tropical herb Anthurium acutifolium. We present ultrastructural morphological details of bee and plant structures involved in this interaction and the composition of floral scents likely mediating pollinator attraction. Inflorescences of A. acutifolium were visited almost exclusively by male P. chocoensis oil bees. The bees mopped with a hairy patch of their abdominal sterna 3 across the inflorescence surface. During this activity on both staminate and pistillate stage inflorescences, bees’ abdomens and legs became loaded with pollen and contacted receptive stigmas. In contrast to what has been observed in other angiosperms visited for the collection of fatty floral oils, the inflorescences/flowers of A. acutifolium do not have structures specialized in oil secretion, i.e., elaiophores. These inflorescences, nonetheless, were strongly scented during the time interval they were visited by the bees. Gas chromatography/mass spectrometry (GC/MS) analyses of dynamic headspace floral samples revealed that inflorescences of both anthetic phases emitted scent bouquets consisting mainly of aliphatic esters, indole and uncommmon terpenoids (megastigmanes). Interestingly enough, our data suggest that the unusual floral scent of A. acutifolium is a perfume reward collected by male P. chocoensis oil bees. This pollination system thus bears a remarkable resemblence with the interactions between perfume-collecting male euglossine bees and their preferred flowers, discovered by Stefan Vogel half a century ago. author: - first_name: Florian full_name: Etl, Florian last_name: Etl - first_name: Anna full_name: Franschitz, Anna id: 480826C8-F248-11E8-B48F-1D18A9856A87 last_name: Franschitz - first_name: Antonio full_name: Aguiar, Antonio last_name: Aguiar - first_name: Jürg full_name: Schönenberger, Jürg last_name: Schönenberger - first_name: Stefan full_name: Dötterl, Stefan last_name: Dötterl citation: ama: 'Etl F, Franschitz A, Aguiar A, Schönenberger J, Dötterl S. A perfume collecting male oil bee? Evidences of a novel pollination system involving Anthurium acutifolium Araceae and Paratetrapedia chocoensis Apidae Tapinotaspidini. Flora: Morphology, Distribution, Functional Ecology of Plants. 2017;232:7-15. doi:10.1016/j.flora.2017.02.020' apa: 'Etl, F., Franschitz, A., Aguiar, A., Schönenberger, J., & Dötterl, S. (2017). A perfume collecting male oil bee? Evidences of a novel pollination system involving Anthurium acutifolium Araceae and Paratetrapedia chocoensis Apidae Tapinotaspidini. Flora: Morphology, Distribution, Functional Ecology of Plants. Elsevier. https://doi.org/10.1016/j.flora.2017.02.020' chicago: 'Etl, Florian, Anna Franschitz, Antonio Aguiar, Jürg Schönenberger, and Stefan Dötterl. “A Perfume Collecting Male Oil Bee? Evidences of a Novel Pollination System Involving Anthurium Acutifolium Araceae and Paratetrapedia Chocoensis Apidae Tapinotaspidini.” Flora: Morphology, Distribution, Functional Ecology of Plants. Elsevier, 2017. https://doi.org/10.1016/j.flora.2017.02.020.' ieee: 'F. Etl, A. Franschitz, A. Aguiar, J. Schönenberger, and S. Dötterl, “A perfume collecting male oil bee? Evidences of a novel pollination system involving Anthurium acutifolium Araceae and Paratetrapedia chocoensis Apidae Tapinotaspidini,” Flora: Morphology, Distribution, Functional Ecology of Plants, vol. 232. Elsevier, pp. 7–15, 2017.' ista: 'Etl F, Franschitz A, Aguiar A, Schönenberger J, Dötterl S. 2017. A perfume collecting male oil bee? Evidences of a novel pollination system involving Anthurium acutifolium Araceae and Paratetrapedia chocoensis Apidae Tapinotaspidini. Flora: Morphology, Distribution, Functional Ecology of Plants. 232, 7–15.' mla: 'Etl, Florian, et al. “A Perfume Collecting Male Oil Bee? Evidences of a Novel Pollination System Involving Anthurium Acutifolium Araceae and Paratetrapedia Chocoensis Apidae Tapinotaspidini.” Flora: Morphology, Distribution, Functional Ecology of Plants, vol. 232, Elsevier, 2017, pp. 7–15, doi:10.1016/j.flora.2017.02.020.' short: 'F. Etl, A. Franschitz, A. Aguiar, J. Schönenberger, S. Dötterl, Flora: Morphology, Distribution, Functional Ecology of Plants 232 (2017) 7–15.' date_created: 2018-12-11T11:47:58Z date_published: 2017-07-01T00:00:00Z date_updated: 2021-01-12T08:09:44Z day: '01' doi: 10.1016/j.flora.2017.02.020 extern: '1' intvolume: ' 232' language: - iso: eng month: '07' oa_version: None page: 7 - 15 publication: 'Flora: Morphology, Distribution, Functional Ecology of Plants' publication_identifier: issn: - '03672530' publication_status: published publisher: Elsevier publist_id: '7007' quality_controlled: '1' status: public title: A perfume collecting male oil bee? Evidences of a novel pollination system involving Anthurium acutifolium Araceae and Paratetrapedia chocoensis Apidae Tapinotaspidini type: journal_article user_id: 4435EBFC-F248-11E8-B48F-1D18A9856A87 volume: 232 year: '2017' ...