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Molecular basis for the nerve dependence of limb regeneration in an adult vertebrate.

ABSTRACT: The limb blastemal cells of an adult salamander regenerate the structures distal to the level of amputation, and the surface protein Prod 1 is a critical determinant of their proximodistal identity. The anterior gradient protein family member nAG is a secreted ligand for Prod 1 and a growth factor for cultured newt blastemal cells. nAG is sequentially expressed after amputation in the regenerating nerve and the wound epidermis-the key tissues of the stem cell niche-and its expression in both locations is abrogated by denervation. The local expression of nAG after electroporation is sufficient to rescue a denervated blastema and regenerate the distal structures. Our analysis brings together the positional identity of the blastema and the classical nerve dependence of limb regeneration.

SUBMITTER: Kumar A

PROVIDER: S-EPMC2696928 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature

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Molecular basis for the nerve dependence of limb regeneration in an adult vertebrate.

Kumar Anoop A Godwin James W JW Gates Phillip B PB Garza-Garcia A Acely AA Brockes Jeremy P JP

Science (New York, N.Y.) 20071101 5851

The limb blastemal cells of an adult salamander regenerate the structures distal to the level of amputation, and the surface protein Prod 1 is a critical determinant of their proximodistal identity. The anterior gradient protein family member nAG is a secreted ligand for Prod 1 and a growth factor for cultured newt blastemal cells. nAG is sequentially expressed after amputation in the regenerating nerve and the wound epidermis-the key tissues of the stem cell niche-and its expression in both loc ...[more]

PMID: 17975060

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