LOCALIZATION OF CORNIFIN IN EPIDERMAL KERATINOCYTE AND ITS EXPRESSION IN SKIN DISEASES

1995 Fiscal Year Final Research Report Summary

• Project/Area Number: 06670865
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Dermatology
• Research Institution: OKAYAMA UNIVERSITY
• Principal Investigator: FUJIMOTO Wataru OKAYAMA UNIVERSITY,HOSPITAL OF MEDICAL SCHOOL,ASSISTANT, 医学部・附属病院, 助手 (50165429)
• Project Period (FY): 1994 – 1995
• Keywords: KERATINOCYTE / CORNIFIN / SPRR / EPIDERMIS / ORAL MUCOUS EPITHELIA / INNER ROOT SHEATH / PSORIASIS

Research Abstract

In this study, the expression of cornifin alpha and beta was compared in several tissues by Northern blot hybridization, immunoblot analyzes, and immunohistochemstry. By Northern blot hybridization, an 0.8 kb cornifinalpha transcript was detected in normal epidermis, psoriatic epidermis, squamous cell carcinoma of the skin, and oral gingival epithelia. The 1.1 kb cornifin beta transcript was detected only in oral gingival epithelia and verrucous carcinoma of the skin, but neither in normal and psoriatic epidermis nor in squamous cell carcinoma of the skin. Immunoblot analysis revealed that SQ37C-Ab for human cornifin alpha/SPRR1, recognized a 14.0-kD protein in extracts from differentiated normal human epidermal keratinocytes, normal epidermis from scalp and sole, and psoriatic epidermis. The antibody recognized 14.0,16.0, and 26.0 kD proteins in extracts from normal gingival epithelia, and 14.0,16.0,25.0 kD proteins, and some proteins with apparent molecular weight smaller than 14.0 kD in extracts from verrucous carcinoma of the skin. The CL 12PEPB-Ab for cornifin beta did not react with extracts from epidermal tissues but strongly recognized a 26.0 kD protein in extracts from gingival epithelial tissues. Analyzes of specimens from normal skin and various skin diseases showed that 1) cornifin alpha was expressed in the granular layr of the epidermis, in the inner root sheath of the hair follicle, and in the upper squamous layrs of oral and esophageal epithelia, 2) cornifin alpha was up-regulated both in hyperplastic, agranulocytic lesions as observed in psoriasis vulgaris and in hypergranulotic lesions as observed in lichen planus, 3) cornifin beta was expressed in normal oral and esophageal epithelia but not in skin and skin diseases, except for verrucous carcinoma.