THE INVOLVEMENT OF CIRCADIAN CLOCK GENE PERIOD IN PHOTOPERIODIC TIME MEASUREMENT OF THE FALL WEBWORM, HYPHANTRIA CUNEA

Author's Name: Dr. Fan Yang , Dr. A S M Kamruzzaman, Dr. Susumu Hiragaki & Dr.Makio Takeda
Subject Area: Life Sciences
Subject Entomology
Section Research Paper

Keyword:

Hyphantria cunea, diapause, period, photoperiodism


Abstract

Photoperiodic response is a crucial adaptation for many insects in temperate regions to survive stressful seasons, typically winter. Mechanisms underlying photoperiodism have not completely been elucidated but the involvement of circadian system has been conventionally conjectured. To examine this possibility, the involvement of period (per) was examined in photoperiodic control of diapause termination in the fall webworm, Hyphantria cunea (Lepidoptera: Arctiidae). Pupal diapause in H. cunea is induced under short days LD 14:10 but can be terminated by exposure to LD 16:8. RNAi by injecting double stranded RNA corresponding to the partial sequence of per stimulated termination of diapause and adult emergence even under LD 14:10, while the dsRNAPER-injected pupae kept under LD 16:8 showed no difference compared with the control pupae. Thus, the present results suggest that the circadian clock regulates photoperiodism of H. cunea where per plays an active role in circadian system.

Download Full Paper