Expression promoter of proline-rich small protein gene SPRR2A

The invention provides a keratinocyte proline-rich small protein gene SPRR2A expression promoter, the keratinocyte proline-rich small protein gene SPRR2A expression promoter is a selaginella pulcherrima extract, and the selaginella pulcherrima extract contains more than or equal to 5.72 wt% of total sugar, more than or equal to 0.3 wt% of total polyphenol and/or more than or equal to 1.12 wt% of total flavone. The invention also relates to an application of the selaginella pad extract as an expression promoter of the proline-rich small protein gene SPRR2A of keratinocytes in a skin external preparation. 本发明提供了一种角质形成细胞富含脯氨酸小蛋白基因SPRR2A的表达促进剂，其中，所述表达促进剂是垫状卷柏提取物，所述垫状卷柏提取物中总糖含量≥5.72wt％，总多酚含量≥0.3wt％，和/或总黄酮含量≥1.12wt％。本发明还涉及垫状卷柏提取物作为角质形成细胞富含脯氨酸小蛋白基因SPRR2A的表达促进剂在皮肤外用剂中的应用。