title: EGFR signaling is required for re-establishing the proximodistal axis during distal leg regeneration in the cricket Gryllus bimaculatus nymph.
abstract: Nymphs of hemimetabolous insects, such as cockroaches and crickets, possess functional legs with a remarkable capacity for epimorphic regeneration. In this study, we have focused on the role of epidermal growth factor receptor (EGFR) signaling in regeneration of a nymphal leg in the cricket Gryllus bimaculatus. We performed loss-of-function analyses with a Gryllus Egfr homolog (Gb'Egfr) and nymphal RNA interference (RNAi). After injection of double-stranded RNA for Gb'Egfr in the body cavity of the third instar cricket nymph, amputation of the leg at the distal tibia resulted in defects of normal distal regeneration. The regenerated leg lacked the distal tarsus and pretarsus. This result indicates that EGFR signaling is required for distal leg patterning in regeneration during the nymphal stage of the cricket. Furthermore, we demonstrated that EGFR signaling acts downstream of the canonical Wnt/Wg signaling and regulates appendage proximodistal (PD) patterning genes aristaless and dachshund during regeneration. Our results suggest that EGFR signaling influences positional information along the PD axis in distal leg patterning of insects, regardless of the leg formation mode.
authors.affiliation: Department of Life Systems, Institute of Technology and Science, The University of Tokushima, 2-1 Minami-Jyosanjima-cho, Tokushima 770-8506, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Nakamura
authors.forename: Taro
authors.initials: T
authors.lastname: Mito
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Miyawaki
authors.forename: Hideyo
authors.initials: H
authors.lastname: Ohuchi
authors.forename: Sumihare
authors.initials: S
authors.lastname: Noji
mesh_terms: D000818:Animals; D019521:Body Patterning; D066246:ErbB Receptors / Q000378:metabolism*; D005121:Extremities / Q000196:embryology; D018507:Gene Expression Regulation, Developmental; D006135:Gryllidae / Q000196:embryology* / Q000378:metabolism; D019476:Insect Proteins / Q000378:metabolism*; D009758:Nymph / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D019476:Insect Proteins; D066246:ErbB Receptors