We have analyzed midgut development during the fifth larval instar in the tobacco budworm Heliothis virescens. In prepupae, the midgut formed during larval instars undergoes a complete renewal process. This drastic remodeling of the alimentary canal involves the destruction of the old cells by programmed cell-death mechanisms (autophagy and apoptosis). Massive proliferation and differentiation of regenerative stem cells take place at the end of the fifth instar and give rise to a new fully functioning epithelium that is capable of digesting and absorbing nutrients and that is maintained throughout the subsequent pupal stage. Midgut replacement in H. virescens is achieved by a balance between this active proliferation process and cell-death mechanisms and is different from similar processes characterized in other insects.
|Titolo:||Programmed cell death and stem cell differentiation are responsible for midgut replacement in Heliothis virescens during prepupal instar|
|Parole Chiave:||Larval midgut replacement ; Programmed cell death ; Regenerative cell proliferation ; Pupal midgut ; Tobacco budworm ; Heliothis virescens (Insecta)|
|Settore Scientifico Disciplinare:||Settore BIO/09 - Fisiologia|
|Data di pubblicazione:||2007|
|Digital Object Identifier (DOI):||10.1007/s00441-007-0449-8|
|Appare nelle tipologie:||01 - Articolo su periodico|