Regulation of leg size and shape by the Dachsous/Fat signalling pathway during regeneration.
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.
Bando
Tetsuya
T
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.
Mito
Taro
T
Maeda
Yuko
Y
Nakamura
Taro
T
Ito
Fumiaki
F
Watanabe
Takahito
T
Ohuchi
Hideyo
H
Noji
Sumihare
S
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*
D015820:Cadherins; D015815:Cell Adhesion Molecules; D019476:Insect Proteins; D025581:Neurofibromin 2