Immune challenge depresses anti-predator behaviour in Manduca sexta: Evidence for an integrated defense system.

Tuesday, November 15, 2022

9:48 AM – 10:00 AM PT

Location: Vancouver Convention Centre, Meeting Room 114/115

Presenting Author(s)

Shelley A. Adamo

Professor
Dalhousie University
Halifax, Nova Scotia, Canada

Co-Author(s)

JZ

Jeffrey Zbarsky

Undergraduate
Dalhousie University
Halifax, Nova Scotia, Canada
SS

Sungwoo Song

Undergraduate
Dalhousie University
Halifax, Nova Scotia, Canada
JK

JongSeok Kim

Undergraduate
Dalhousie University
Halifax, Nova Scotia, Canada
EC

Emily Corkum

Undergraduate
Dalhousie University
Halifax, Nova Scotia, Canada
IZ

Isaac Zacher

Undergraduate
Dalhousie University
Halifax, Nova Scotia, Canada
DM

Dylan Miller

Graduate Student
Dalhousie University
Halifax, Nova Scotia, Canada
Laura E. McMillan

Postdoctoral Fellow
Dalhousie University
Halifax, Nova Scotia, Canada

Defense against pathogens, predators and poisons are deeply intertwined at the physiological and cellular level in insects. We demonstrate that muscle in the caterpillar Manduca sexta responds to an immune challenge, and shows a concomitant reduction in anti-predator behaviour. Body wall muscle, critical for anti-predator behaviour, expressed toll-1, the gene for a receptor that is activated during an immune response. Expression of toll-1 in muscle increased during a systemic immune challenge, but not in response to chronic predator stress. During an immune response, the amount of glycogen in body wall muscle declined. At the same time, the muscular force of the caterpillar’s primary anti-predator behaviour, the defensive strike, also declined. This decline was biologically significant, leading to a reduction in the ability of caterpillars to repel attacks by the parasitic wasp Cotesia congregata. Muscle appears to donate resources during an immune challenge, resulting in a reduction in anti-predator behaviour.