Innate expression of antimicrobial peptides does not explain genotypic diversity in resistance to fungal brood parasites in the honey bee

TY - JOUR

T1 - Innate expression of antimicrobial peptides does not explain genotypic diversity in resistance to fungal brood parasites in the honey bee

AU - Evison, Sophie E.F.

AU - Fazio, Geraldine

AU - Chappell, Paula

AU - Foley, Kirsten

AU - Jensen, Annette Bruun

AU - Hughes, William O.H.

PY - 2016/3/1

Y1 - 2016/3/1

N2 - The genetic basis of host resistance to parasites is a fundamental aspect of host-parasite co-evolution, yet the precise mechanisms often remain unclear. Here, we follow on from a previous study on the genetically mediated variation in resistance to two common fungal brood parasites that cause chalkbrood and stonebrood in the honey bee. We assessed whether genetically mediated variation in resistance can be explained by the baseline immunocompetence of different larval genotypes by correlating the constitutive expression of two key immune genes with the observed level of resistance of each larval genotype to four different fungal brood parasites. We found significant variation between larval genotypes in the constitutive expression of abaecin but not defensin 2, but despite a suggestion of negative correlations between gene expression and resistance level in older larvae, there was no consistent evidence that baseline abaecin expression is a relevant predictor of resistance to these parasites. These results suggest that the constitutive expression of abaecin appears to have a genetic basis in honey bee larvae but that mechanisms other than innate expression of antimicrobial peptides might be more important in defence against the specific fungal brood parasites assessed here.

AB - The genetic basis of host resistance to parasites is a fundamental aspect of host-parasite co-evolution, yet the precise mechanisms often remain unclear. Here, we follow on from a previous study on the genetically mediated variation in resistance to two common fungal brood parasites that cause chalkbrood and stonebrood in the honey bee. We assessed whether genetically mediated variation in resistance can be explained by the baseline immunocompetence of different larval genotypes by correlating the constitutive expression of two key immune genes with the observed level of resistance of each larval genotype to four different fungal brood parasites. We found significant variation between larval genotypes in the constitutive expression of abaecin but not defensin 2, but despite a suggestion of negative correlations between gene expression and resistance level in older larvae, there was no consistent evidence that baseline abaecin expression is a relevant predictor of resistance to these parasites. These results suggest that the constitutive expression of abaecin appears to have a genetic basis in honey bee larvae but that mechanisms other than innate expression of antimicrobial peptides might be more important in defence against the specific fungal brood parasites assessed here.

U2 - 10.1007/s13592-015-0388-4

DO - 10.1007/s13592-015-0388-4

M3 - Journal article

SN - 0044-8435

VL - 47

SP - 206

EP - 215

JO - Apidologie

JF - Apidologie

IS - 2

ER -