Keeping Up Defenses

Abstract

Protective barriers in animals, whether the skin of mammals or cuticle in insects, help prevent dehydration and protect against injury. A conserved innate immune system functions in both vertebrates and invertebrates to combat infectious microbes introduced by epidermal injury. However, less is known about the mechanisms for the aseptic wounding response (see the Perspective by Harden). Mace et al. now describe a wound response pathway in Drosophila , which is mediated by the factor grainy head and which senses aseptic breaks in the epidermis. The grainy-head-mediated response provides cross-linking molecules to fix the cuticular barrier. Complementary work by Ting et al. suggests that this type of barrier wound response pathway is conserved--mice with a mutation in a mouse grainy head ortholog show defects in epidermal wound repair. N. Harden, Of grainy heads and broken skins. Science 308 , 364-365 (2005). [Summary] [Full Text] K. A. Mace, J. C. Pearson, W. McGinnis, An epidermal barrier wound repair pathway in Drosophila is mediated by grainy head . Science 308 , 381-385 (2005). [Abstract] [Full Text] S. B. Ting, J. Caddy, N. Hislop, T. Wilanowski, A. Auden, L.-L. Zhao, S. Ellis, P. Kaur, Y. Uchida, W. M. Holleran, P. M. Elias, J. M. Cunningham, S. M. Jane, A homolog of Drosophila grainy head is essential for epidermal integrity in mice. Science 308 , 411-413 (2005). [Abstract] [Full Text]