Characterization of a newt tenascin cDNA and localization of tenascin mRNA during newt limb regeneration by in situ hybridization

摘要: We previously showed that tenascin, a large, extracellular matrix glycoprotein, exhibits temporally and spatially restricted distribution during urodele limb regeneration. To further investigate the role of tenascin in regeneration, we cloned newt cDNA, NvTN.1, has 70% homology to chicken sequence. A deduced amino acid sequence NvTN.1 modular structure unique characterized by epidermal growth factor-like fibronectin type III repeats. determine cellular origin protein localized transcripts situ hybridization using riboprobe synthesized from NvTN.1. Transcripts could not be detected normal tissues but first became detectable wound epithelium at 2 days distal mesoderm 5 after amputation. These epithelial cells are probably source found within immediately underneath epithelium. At preblastema stages, was seen associated with most mesodermal dermis. blastema essentially every mesenchymal cell contained transcripts. Thus, regardless origin, blastemal may share common regulatory mechanism results gene transcription. Finally, redifferentiation stages transcription both differentiation growth. The show initiation expression is an early event regeneration continued some important processes namely epithelial-mesenchymal interactions, dedifferentiation, cycling, outgrowth, differentiation.