---
_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
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- 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'
...