title: Regulation of leg size and shape by the Dachsous/Fat signalling pathway during regeneration.
abstract: An amputated cricket leg regenerates all missing parts with normal size and shape, indicating that regenerating blastemal cells are aware of both their position and the normal size of the leg. However, the molecular mechanisms regulating this process remain elusive. Here, we use a cricket model to show that the Dachsous/Fat (Ds/Ft) signalling pathway is essential for leg regeneration. We found that knockdown of ft or ds transcripts by regeneration-dependent RNA interference (rdRNAi) suppressed proliferation of the regenerating cells along the proximodistal (PD) axis concomitantly with remodelling of the pre-existing stump, making the regenerated legs shorter than normal. By contrast, knockdown of the expanded (ex) or Merlin (Mer) transcripts induced over-proliferation of the regenerating cells, making the regenerated legs longer. These results are consistent with those obtained using rdRNAi during intercalary regeneration induced by leg transplantation. We present a model to explain our results in which the steepness of the Ds/Ft gradient controls growth along the PD axis of the regenerating leg.
authors.affiliation: Department of Life Systems, Institute of Technology and Science, The University of Tokushima Graduate School, 2-1 Minami-Jyosanjima-cho, Tokushima city, 770-8506, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Bando
authors.forename: Taro
authors.initials: T
authors.lastname: Mito
authors.forename: Yuko
authors.initials: Y
authors.lastname: Maeda
authors.forename: Taro
authors.initials: T
authors.lastname: Nakamura
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Ito
authors.forename: Takahito
authors.initials: T
authors.lastname: Watanabe
authors.forename: Hideyo
authors.initials: H
authors.lastname: Ohuchi
authors.forename: Sumihare
authors.initials: S
authors.lastname: Noji
mesh_terms: D000818:Animals; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D005121:Extremities / Q000033:anatomy & histology / Q000502:physiology; D006135:Gryllidae / Q000033:anatomy & histology / Q000502:physiology; D017403:In Situ Hybridization; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D025581:Neurofibromin 2 / Q000235:genetics / Q000378:metabolism; D012038:Regeneration / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D015820:Cadherins; D015815:Cell Adhesion Molecules; D019476:Insect Proteins; D025581:Neurofibromin 2