Functional redundancy of extracellular matrix protein 1 in epidermal differentiation
Extracellular matrix protein 1 (ECM1) is a secreted protein expressed in skin. Its dermatological relevance has been highlighted by the discovery of loss-of-function mutations in ECM1 in patients with lipoid proteinosis (LiP). Objectives
To determine the role of ECM1 in epidermal differentiation by examining gene and protein expression of epidermal differentiation markers in individuals with LiP and histological assessment of transgenic mouse skin that overexpresses Ecm1a in basal or suprabasal epidermis. Methods
Subconfluent, confluent and postconfluent LiP and control keratinocyte cultures were analysed by Northern and Western blotting for differences in expression of differentiation markers. Expression of these markers was analysed in skin of patients with LiP by immunohistochemistry. To study effects of Ecm1 overexpression on epidermal differentiation, transgenic mice were generated under control of either a keratin 14 or an involucrin promoter. Results
No differential expression of the different markers analysed was observed in LiP keratinocytes compared with controls. No histological differences were found in Ecm1-overexpressing mouse skin compared with wild-type. Conclusions
Absence of ECM1 does not lead to differences in epidermal differentiation. Moreover, overexpression of Ecm1a in vivo does not exert dramatic effects on epidermal structure. Collectively, these findings suggest no role of ECM1 in epidermal differentiation.
Document Type: Research Article
Affiliations: 1: Cell and Tissue Laboratory, URPHYM, University of Namur, Namur, Belgium 2: Genetic Skin Disease Group, St John’s Institute of Dermatology, Division of Genetics and Molecular Medicine, The Guy’s, King’s College and St Thomas’ School of Medicine, King’s College London, London, U.K.
Publication date: October 1, 2007