User:Akiegami: Difference between revisions
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''Ophiocordyceps unilateralis s.l'' is a parasite that primarily infects Golden Carpenter ants from the Campotini tribe (Lin et. Al 2020). Recent studies, however, demonstrated that a member of this species complex could sympatrically infect ant species from the Polyrachis and Camponotus genera, strongly suggesting that this species complex has a broader range of hosts (Lin et. Al 2020). | ''Ophiocordyceps unilateralis s.l'' is a parasite that primarily infects Golden Carpenter ants from the Campotini tribe (Lin et. Al 2020). Recent studies, however, demonstrated that a member of this species complex could sympatrically infect ant species from the Polyrachis and Camponotus genera, strongly suggesting that this species complex has a broader range of hosts (Lin et. Al 2020). | ||
The main objective of ''Ophiocordyceps unilateralis s.l'' pathogenesis is propagation (Lin et. Al 2020). ''Ophiocordyceps unilateralis s.l'' begins by utilizing ascospores to infect ants wandering around on the forest floor (Lin et. Al 2020). It is thought that some sort of signaling or host recognition factor mechanism initiates the production of enzymes and other infection mechanisms to penetrate the exoskeleton of the ant (Evans et. Al 2011). Experimental data suggests that ''Ophiocordyceps unilateralis s.l'' utilizes secondary metabolites to control the behavior of the ant, directing it to climb up plants (Lu et. Al 2024, Lin et. Al 2020). Once on the underside of leaves/twigs, ''Ophiocordyceps unilateralis s.l'' induces the famous “death grip” wherein the ant is forced to bite and hang onto major veins in the leaf (Lin et. Al 2020). Rhizoids and mycelial structures are produced by the fungus to further secure it in place (Lu et. Al 2024). Some researchers think that the death grip mechanism occurs specifically on the leaf veins so that the fungus can use nutrients from the plant vascular system for growth purposes (Lin et. Al 2020). It takes about one to two weeks for | The main objective of ''Ophiocordyceps unilateralis s.l'' pathogenesis is propagation (Lin et. Al 2020). ''Ophiocordyceps unilateralis s.l'' begins by utilizing ascospores to infect ants wandering around on the forest floor (Lin et. Al 2020). It is thought that some sort of signaling or host recognition factor mechanism initiates the production of enzymes and other infection mechanisms to penetrate the exoskeleton of the ant (Evans et. Al 2011). Experimental data suggests that ''Ophiocordyceps unilateralis s.l'' utilizes secondary metabolites to control the behavior of the ant, directing it to climb up plants (Lu et. Al 2024, Lin et. Al 2020). Once on the underside of leaves/twigs, ''Ophiocordyceps unilateralis s.l'' induces the famous “death grip” wherein the ant is forced to bite and hang onto major veins in the leaf (Lin et. Al 2020). Rhizoids and mycelial structures are produced by the fungus to further secure it in place (Lu et. Al 2024). Some researchers think that the death grip mechanism occurs specifically on the leaf veins so that the fungus can use nutrients from the plant vascular system for growth purposes (Lin et. Al 2020). It takes about one to two weeks for ''Ophiocordyceps unilateralis s.l'' to produce fruiting structures from the dead ant so that more ascospores can be released onto the forest floor enabling the infection cycle to continue (Lin et. Al 2020). One interesting thing to note is that ''Ophiocordyceps unilateralis s.l'' produces both hyphae and yeast-like cells for structural support during its growth stage on the dead ant (Andersen et. Al 2009). | ||
From an ecological perspective, ''Ophiocordyceps unilateralis s.l'' holds great importance as it gives us useful insight into the different types of host-microbe interactions that occur in rainforests (Evans et. Al 2011). A lot is still unknown about the ''Ophiocordyceps unilateralis s.l'' species complex so more research needs to be done for a better understanding of its ecosystem functioning (Evans et. Al 2011). | From an ecological perspective, ''Ophiocordyceps unilateralis s.l'' holds great importance as it gives us useful insight into the different types of host-microbe interactions that occur in rainforests (Evans et. Al 2011). A lot is still unknown about the ''Ophiocordyceps unilateralis s.l'' species complex so more research needs to be done for a better understanding of its ecosystem functioning (Evans et. Al 2011). | ||
Revision as of 21:58, 13 December 2025
Ophiocordyceps unilateralis
Domain: Eukarya
Phylum: Ascomycota
Class: Sordariomycetes
Order: Hypocerales
Family: Ophiocordycipitaceae
Species
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NCBI: [1] |
Ophiocordyceps unilateralis
Ophiocordyceps unilateralis s.l.
Background
Ophiocordyceps unilateralis was first discovered by biologist Alfred Russel Wallace in 1859 (Hughes et. Al 2011). The fungus was further described by Louis and Charles Tulasne who drew illustrations of it infecting ants (Evans et. Al 2017). Scientific papers often refer to this fungus as Ophiocordyceps unilateralis s.l (sensu lato - in a broad sense) due to the fact that it is actually a species complex consisting of distinct individuals (Evans et. Al 2011). Ophiocordyceps unilateralis infects Campotini ants, turning them into zombies and utilizing them as tools for propagation (Hughes et. Al 2011, Evans et. Al 2017). Numerous studies have focused on characterizing the infection mechanisms and secondary metabolites produced by this fungus in order to better understand how it manipulates its ant hosts (Hughes et. Al 2011, Bekker et. Al 2017). Ophiocordyceps unilateralis is commonly found in tropical forest environments throughout the world (Evans et. Al 2011).
Morphology
Ophiocordyceps unilateralis s.l produces both sexual and asexual structures. The teleomorph of this fungus is defined by the production of a clava on the back of the head with a stromal plate (Evans et. Al 2011). Embedded into the stromal plates are numerous ascomata which produce ascospore containing asci (Evans et. Al 2011). On the other hand, different variations of the anamorph exist with one example being the sporodochium which are dense hyphal masses with conidia (Evans et. Al 2017; Henry et. Al 2023). However, the morphological characteristic that sets Ophiocordyceps unilateralis s.l apart from all other ant-infecting fungi is the fact that they produce both type A and B phialides on the hymenium of their stromatal clava (Evans et Al. 2017).
Genome Structure
Because Ophiocordyceps unilateralis s.l is a species complex, there is a considerable amount of variation in the genome structure. A study conducted in 2024 found that the genome size of seven Ophiocordyceps unilateralis s.l specimens ranged from 27.80 to 51.00 mb with the GC content ranging from 41.81-53.22% (Lu et. Al 2024). The same study also found that the variation in total number of genes, which ranged from 6700 to 6974, was relatively small (Lu et. Al 2024). Yet, another study found that the genome structure of a South Carolinian Ophiocordyceps unilateralis s.l specimen was around 26.05 mb with 7831 putative genes (Bekker et. Al 2015). The bottom line is that the genome structure of this species complex varies quite a lot from specimen to specimen.
Ecology and Pathogenesis
Ophiocordyceps unilateralis s.l is a parasite that primarily infects Golden Carpenter ants from the Campotini tribe (Lin et. Al 2020). Recent studies, however, demonstrated that a member of this species complex could sympatrically infect ant species from the Polyrachis and Camponotus genera, strongly suggesting that this species complex has a broader range of hosts (Lin et. Al 2020).
The main objective of Ophiocordyceps unilateralis s.l pathogenesis is propagation (Lin et. Al 2020). Ophiocordyceps unilateralis s.l begins by utilizing ascospores to infect ants wandering around on the forest floor (Lin et. Al 2020). It is thought that some sort of signaling or host recognition factor mechanism initiates the production of enzymes and other infection mechanisms to penetrate the exoskeleton of the ant (Evans et. Al 2011). Experimental data suggests that Ophiocordyceps unilateralis s.l utilizes secondary metabolites to control the behavior of the ant, directing it to climb up plants (Lu et. Al 2024, Lin et. Al 2020). Once on the underside of leaves/twigs, Ophiocordyceps unilateralis s.l induces the famous “death grip” wherein the ant is forced to bite and hang onto major veins in the leaf (Lin et. Al 2020). Rhizoids and mycelial structures are produced by the fungus to further secure it in place (Lu et. Al 2024). Some researchers think that the death grip mechanism occurs specifically on the leaf veins so that the fungus can use nutrients from the plant vascular system for growth purposes (Lin et. Al 2020). It takes about one to two weeks for Ophiocordyceps unilateralis s.l to produce fruiting structures from the dead ant so that more ascospores can be released onto the forest floor enabling the infection cycle to continue (Lin et. Al 2020). One interesting thing to note is that Ophiocordyceps unilateralis s.l produces both hyphae and yeast-like cells for structural support during its growth stage on the dead ant (Andersen et. Al 2009).
From an ecological perspective, Ophiocordyceps unilateralis s.l holds great importance as it gives us useful insight into the different types of host-microbe interactions that occur in rainforests (Evans et. Al 2011). A lot is still unknown about the Ophiocordyceps unilateralis s.l species complex so more research needs to be done for a better understanding of its ecosystem functioning (Evans et. Al 2011).
References
Author
Page authored by Aki Egami, student of Dr. Marc Orbach, University of Arizona .
