TY - JOUR

T1 - Cross-resistance

T2 - A consequence of bi-partite host-parasite coevolution

AU - Biswas, Tilottama

AU - Joop, Gerrit

AU - Rafaluk-Mohr, Charlotte

N1 - Funding Information: The project was funded by a German Science Foundation grant (Deutsche Forschungsgemeinschaft DFG-SPP 1399, JO 962/1-1) and a Volkswagen advanced postdoctoral grant awarded to Gerrit Joop (87133). Publisher Copyright: © 2018 by the authors.

PY - 2018/3/1

Y1 - 2018/3/1

N2 - Host-parasite coevolution can influence interactions of the host and parasite with the wider ecological community. One way that this may manifest is in cross-resistance towards other parasites, which has been observed to occur in some host-parasite evolution experiments. In this paper, we test for cross-resistance towards Bacillus thuringiensis and Pseudomonas entomophila in the red flour beetle Tribolium castaneum, which was previously allowed to coevolve with the generalist entomopathogenic fungus Beauveria bassiana. We combine survival and gene expression assays upon infection to test for cross-resistance and underlying mechanisms. We show that larvae of T. castaneum that evolved with B. bassiana under coevolutionary conditions were positively cross-resistant to the bacterium B. thuringiensis, but not P. entomophila. Positive cross-resistance was mirrored at the gene expression level with markers that were representative of the oral route of infection being upregulated upon B. bassiana exposure. We find that positive cross-resistance towards B. thuringiensis evolved in T. castaneum as a consequence of its coevolutionary interactions with B. bassiana. This cross-resistance appears to be a consequence of resistance to oral toxicity. The fact that coevolution with B. bassiana results in resistance to B. thuringiensis, but not P. entomophila implies that B. thuringiensis and B. bassiana may share mechanisms of infection or toxicity not shared by P. entomophila. This supports previous suggestions that B. bassiana may possess Cry-like toxins, similar to those found in B. thuringiensis, which allow it to infect orally.

AB - Host-parasite coevolution can influence interactions of the host and parasite with the wider ecological community. One way that this may manifest is in cross-resistance towards other parasites, which has been observed to occur in some host-parasite evolution experiments. In this paper, we test for cross-resistance towards Bacillus thuringiensis and Pseudomonas entomophila in the red flour beetle Tribolium castaneum, which was previously allowed to coevolve with the generalist entomopathogenic fungus Beauveria bassiana. We combine survival and gene expression assays upon infection to test for cross-resistance and underlying mechanisms. We show that larvae of T. castaneum that evolved with B. bassiana under coevolutionary conditions were positively cross-resistant to the bacterium B. thuringiensis, but not P. entomophila. Positive cross-resistance was mirrored at the gene expression level with markers that were representative of the oral route of infection being upregulated upon B. bassiana exposure. We find that positive cross-resistance towards B. thuringiensis evolved in T. castaneum as a consequence of its coevolutionary interactions with B. bassiana. This cross-resistance appears to be a consequence of resistance to oral toxicity. The fact that coevolution with B. bassiana results in resistance to B. thuringiensis, but not P. entomophila implies that B. thuringiensis and B. bassiana may share mechanisms of infection or toxicity not shared by P. entomophila. This supports previous suggestions that B. bassiana may possess Cry-like toxins, similar to those found in B. thuringiensis, which allow it to infect orally.

KW - Bacillus thuringiensis

KW - Beauveria bassiana

KW - Multiple parasites

KW - Pseudomonas entomophila

KW - Route of infection

KW - RT-qPCR

KW - Tribolium castaneum

KW - Ecosystems Research

UR - http://www.scopus.com/inward/record.url?scp=85046423184&partnerID=8YFLogxK

U2 - 10.3390/insects9010028

DO - 10.3390/insects9010028

M3 - Journal articles

C2 - 29495405

AN - SCOPUS:85046423184

VL - 9

JO - Insects

JF - Insects

SN - 2075-4450

IS - 1

M1 - 28

ER -