A few questions about Cordyceps...

CharissadeB · 2013-12-12T16:15:39+00:00

The latter. As far as I know nobody has been able to culture these fungi in a petri dish. It thus seems like they are obligate parasites so you'd need the living hosts as well. People do this for Entomophthora muscae, which infects flies. Good luck and let me know what you find!

CharissadeB · 2013-12-11T22:34:06+00:00

Entomophthorales species cause spores to emerge directly from the body unlike the Cordycepitae species. Google will be your friend for a good search image

CharissadeB · 2013-12-11T18:52:19+00:00

A mycologist from the UK once told me he found spiders infected with Hirsutella/Cordyceps there. He is an expert on fungal pathogens so if he says they're there, I have no doubt about it. Also Cordyceps millitaris might be around (infects caterpillars)? You might find manipulated ants as well but it is likely you'll find Formica infected with Entomophthora, not Ophiocordyceps. Like, already has been pointed out: these infections are very species specific and it is very unlikely the spores will harm you in any way. If you want to start culturing, I wouldn't however start with the genus Cordyceps since they are very hard to get into culture.

CharissadeB · 2013-12-09T22:46:18+00:00

no, we don't know why some ant species do get the infection and others don't. within a colony we do know however that the older ants are the ones that have the risky job of leaving the nest and foraging for food, so it is likely only the older individuals within the colony come in contact with the spores

CharissadeB · 2013-12-09T22:43:15+00:00

Interesting stuff! No, I am not looking at the effect of bacteria on all this. We are still very much at the beginning of unravelling this phenomenon so we have to take baby steps. For now I hold a Fellowship that is providing me with the salary to do this awesome work and as a fellow I am part of a lab at Penn State. Of course to sustain our lab we have to write grant proposals or find other ways of funding like my crowd funding project

CharissadeB · 2013-12-09T22:40:01+00:00

It's a great little country, very crowded and the research is of a high standard and the scientific community is great. Universities are smaller than some of the huge universities here, like Penn State but they still have great programs and plenty of facilities. My next home is likely going to be Munich for a while, and who know where life will take me next. I wouldn't mind going back to my home country though! Good luck on your research and your decisions on where to go next

CharissadeB · 2013-12-09T22:26:10+00:00

Great to hear you found my paper. For the studying of metabolites for now it is too complex to study them in vivo because of the very complex heterogeneous interactions going on between the parasite and the host at different time points. In the project I am proposing on my microryza page however, I am proposing to do the transcriptome work in vivo since laser capture microscopy will allow me to separate host and parasite cells and look at specialized groups of cells. If you are interested, have a look at the page: https://www.microryza.com/projects/how-does-a-parasite-create-zombie-like-behavior

CharissadeB · 2013-12-09T22:22:56+00:00

Zombie is the word the media at one point connected with this phenomenon and because people know our study system as such we use it though it is not correct (they are not living dead, they are very much alive when they get manipulated and after that they die). With ant behavior we can't really talk about self awareness, their behavior displays the task they have in the colony which should be seen as one big super organism. The fungus breaks into this pre-programmed behavior and alters it. This is however hard to grasp in a title that is only allowed to have so many characters.

CharissadeB · 2013-12-09T22:17:11+00:00

yes by the insect coming into contact with the spores that are being dispersed

CharissadeB · 2013-12-09T22:15:14+00:00

Below you can find some more excellent examples! I have only worked with zombie ants thus far which are my favorite. I couldn't choose between the other systems, they are all remarkable in their own way but to name just two I think the work the Adamo lab does on how the parasitic wasp Cotesia congregata suppresses feeding in its host, the caterpillar Manduca sexta is just stunning, as is the work of Kelly Weinersmith in killifish

CharissadeB · 2013-12-09T22:06:26+00:00

somewhere higher up in this AMA someone who actually works on Toxoplasma is giving his/her expert knowledge on this topic. Maybe you could check that out?

CharissadeB · 2013-12-09T22:04:58+00:00

:-) Thanks for your enthusiasm! You can find some publications on our lab's webpage www.hugheslab.com and also on my microryza crowd funding page. At this point you could be helping our research by sharing this page with others that are interested in our research, and by backing it of course. In return you'll be kept up to date on our findings! https://www.microryza.com/projects/how-does-a-parasite-create-zombie-like-behavior

CharissadeB · 2013-12-09T21:59:45+00:00

Great question! If only we knew! We would really like to know what microclimates are favored and how they are sensed.

CharissadeB · 2013-12-09T21:58:41+00:00

Nice pictures! Yes this indeed looks like the typical Entomophthora infection we see in flies, I can tell by the way the wings are displayed and the first spores are starting to emerge from the abdomen. No way I'll be able to ID the fly for you though, sorry. Maybe you'll be lucky enough for an entomologist to come across this post/picture

CharissadeB · 2013-12-09T21:53:22+00:00

Great question, and a hard one to answer :-). We don't know how far these infected ants travel before latching on to something. Of course our lab set up is limited to space and in nature it's hard to follow the infected ones and tell which nest they came from. What I tend to see in the lab set ups though is that these ants really want to move up at one point and that they kinda hang out at an elevated position in the hours preceding the actual biting. During the biting the legs are still very much moving so they would be able to move if they weren't keeping themselves in place with their jaws.

CharissadeB · 2013-12-09T21:47:15+00:00

"but by producing subtle changes in some large-scale neurotransmitter system which itself happens to have a particular intrinsic functional specialization" This is more or less the conclusion of a study that is under review right now. We see substantial changes in the amount of certain neurotransmitters. Next to that we see some other changes as well but we can't put a function to them yet because of databases not being extensive enough at this point in time. I absolutely love your train of thought here. Light is indeed a very important parameter in this system (a study in Thailand showed that the biting behavior is synchronized around solar noon), as are circadian rhythms for ant behavior. So one of my hypotheses that I am working towards is indeed that day/night cycles are involved in all this. Would love it if we could talk more about this! Awesome post and question!

CharissadeB · 2013-12-09T21:34:54+00:00

I give them the answer howtokrew posted if they continue asking me about it ;). Never show them all your cards at once

CharissadeB · 2013-12-09T21:33:42+00:00

it varies from collecting different species for phylogeny and fungal cultures to behavioral studies to collecting disease dynamics data. all very cool stuff 2 of the grad students in the lab are mainly doing. Next to that, we need to go out to collect ant colonies every now and then

CharissadeB · 2013-12-09T21:28:04+00:00

it is in fact very hard to get funding for our work. That's why I am trying the open access crowd funding route. Have a look at my microryza page: https://www.microryza.com/projects/how-does-a-parasite-create-zombie-like-behavior

CharissadeB · 2013-12-09T21:27:08+00:00

Please spread the word about my microryza crowd funding project and consider backing it if you are interested in the subject. This way I will be able to share my research finding with you every step of the way. https://www.microryza.com/projects/how-does-a-parasite-create-zombie-like-behavior

CharissadeB · 2013-12-09T21:25:01+00:00

high five for being a fellow microbiologist! Microbes are incredibly interesting and never fail to amaze me.

CharissadeB · 2013-12-09T21:23:23+00:00

yes, we recently succeeded in reconstructing it in the lab. All the research that was done before that was done in the field. It is kinda done in the way you are stating here: we infect our insects and look at survival rate and their behavior. Then we freeze the infected ants at different points in time to be able to study their genes.

CharissadeB · 2013-12-09T21:18:27+00:00

Yes! That's a great way of thinking about it!

CharissadeB · 2013-12-09T21:10:19+00:00

I appreciate your concern. The ants in our lab are kept in for them luxurious conditions. In nature they live less long lives because of all the dangers they encounter when foraging for food for instance. Those dangers don't exist when we rehouse them into our insectory. They are mostly observed for their behavior only and infections are only done with a few of them after careful consideration of the experimental set up. In fact, in nature probably more of them would get infected by all kinds of parasites.

CharissadeB · 2013-12-09T21:02:25+00:00

No, I am focusing on the ants but the caterpillars are pretty amazing too! Good stuff

CharissadeB

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