title: Gain of long tonic immobility behavioral trait causes the red flour beetle to reduce anti-stress capacity.
abstract: Tonic immobility (death-feigning) behavior of the red flour beetle, Tribolium castaneum, is a predator defense mechanism; it is a reflex elicited when a beetle is jarred with the substrate, often a result of the activities of a predator. We previously demonstrated that the frequency of predation by a jumping spider, Hasarius adansoni, was significantly lower among beetles with higher frequencies and longer durations of tonic immobility (L-type) than those with lower frequencies and shorter durations of tonic immobility (S-type). However, we found that the population of L-type beetles is much smaller than that of S-type beetles in their natural habitat. Here we demonstrated that L-type beetles are significantly more sensitive to environmental stressors such as mechanical vibration and high or low temperatures. We measured expression levels of stress-responsive genes such as heat shock proteins (Hsps) and antioxidant enzymes in both types of beetles. Among the genes we investigated, only catalase gene expression levels were significantly higher in S-type than in L-type beetles. Furthermore, a similar difference in the gene expression was observed in the T. castaneum ortholog of the insect cytokine growth-blocking peptide (GBP) gene. These results indicate the possibility that high expression of catalase and GBP in S-type beetles contributes to augmentation of their anti-stress capacity and expansion of their population in their natural habitat.
authors.affiliation: Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan.
authors.forename: Hikaru
authors.initials: H
authors.lastname: Kiyotake
authors.affiliation: Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Matsumoto
authors.affiliation: Faculty of Science, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakayama
authors.affiliation: Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Sakai
authors.affiliation: Faculty of Agriculture, Okayama University, Okayama 700-8530, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Miyatake
authors.affiliation: Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan.
authors.forename: Masasuke
authors.initials: M
authors.lastname: Ryuda
authors.affiliation: Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan. Electronic address: hayakayo@cc.saga-u.ac.jp.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Hayakawa
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D002374:Catalase / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D005979:Glutathione Peroxidase / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism; D046353:Immobility Response, Tonic; D019476:Insect Proteins / Q000378:metabolism*; D008297:Male; D013312:Stress, Physiological; D013482:Superoxide Dismutase / Q000378:metabolism; D014231:Tribolium / Q000201:enzymology*
chemical_list: D016207:Cytokines; D006360:Heat-Shock Proteins; D019476:Insect Proteins; C068690:growth blocking peptide, Apanteles kariyai; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase
keywords: Catalase; Death-feigning; Growth-blocking peptide (GBP); Stress; Tonic immobility; Tribolium castaneum