CHANGES IN THE DISTRIBUTION OF ACTIN-ASSOCIATED PROTEINS DURING EPIDERMAL WOUND-HEALING

We have examined the distribution of actin filaments and a number of a ctin-associated proteins during human epidermal wound.healing, using a suction blister model in which the epidermis is detached from the der mis, leaving the basement membrane intact. Filamentous actin was found in all the living epidermal layers before, during and after wound hea ling alpha-actinin was also present in all the living layers of normal epidermis, but diffuse cytoplasmic staining was observed at the leadi ng edge of migrating epidermis. Vinculin and talin were concentrated a t the basement membrane prior to wounding, but were absent from the le ading edge during wound healing. In normal epidermis, filamin and gels olin showed a complementary distribution, with filamin most abundant i n the basal layer and gelsolin most abundant suprabasally. The abundan ce of both proteins was reduced at the leading edge of migrating epide rmis. All of the changes were transient, as the expression patterns re turned to normal by 1 week after wounding, when the epidermis had refo rmed. The relevance of these changes to the process of keratinocyte mi gration is discussed.