Cloning of cDNAs specifying vitamin A-responsive human keratins

In human cultured epidermal and conjunctival keratinocytes, vitamin A promotes the synthesis of keratins 13 and 19 of the catalog of Moll et al. [Moll, R., Franke, W.W., Schiller, D.L., Geiger, B. & Krepler, R. (1982) Cell 31, 11-24] but does not alter the synthesis of keratins 5 and 6. To study this effect of the vitamin, cDNAs specifying each of these keratins were cloned in pBR322. Characterization of the clones by hybrid selection of mRNA and by hybridization of size-fractionated mRNA indicated that each was specific for a single mRNA. Treatment of epidermal cells with arotinoid Ro 13-6298, a potent synthetic analog of retinoic acid, increased the abundance of mRNA for keratin 13 by 25-fold and for keratin 19 by greater than 40-fold but had no effect on the abundance of mRNA for keratins 5 and 6.