Hwang M, Kalinin A, Morasso M I
Developmental Skin Biology Unit, NIAMS, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Building 50 Room 1525, Bethesda, MD 20892, USA.
Gene Expr Patterns. 2005 Aug;5(6):801-8. doi: 10.1016/j.modgep.2005.03.010.
During the process of epidermal differentiation, intracellular and extracellular calcium (Ca++) concentrations induce an array of signaling pathways . Keratinocytes follow a complex Ca++-dependent program of differentiation moving from the basal proliferative layer, through the spinous and granular differentiated layers to ultimately culminate in the formation of the cornified layer of the epidermis. Members of the Ca++-binding proteins play a central role in the transduction of Ca++ signals. Utilizing a suppressive subtractive hybridization screen comparing basal and differentiated keratinocytes, we identified the novel Ca++-binding protein genes, Scarf (skin Calmodulin-related factor) and Scarf2, which have homology to calmodulin (CaM). In this study, we present a comprehensive analysis of the expression pattern for Scarf and Scarf2 transcripts and proteins in the developing mouse. To examine Scarf2 expression during embryogenesis, we performed in situ hybridization, and detected expression in the hair follicle, skin and nasal epithelium. These results showed substantial overlap with the previously reported Scarf gene expression [Hwang, M., Morasso, M.I., 2003. The novel murine Ca2+-binding protein, Scarf, is differentially expressed during epidermal differentiation. J. Biol. Chem. 278, 47827-47833]. Comparing the expression patterns of Scarf and Scarf2 proteins in neonatal and adult mouse skin with several structural epidermal proteins, i.e. keratin 14 (K14), keratin 1 (K1), loricrin (LOR) and filaggrin (FIL) showed that their expression overlaps K1, an early marker of keratinocyte differentiation. Interestingly, Scarf and Scarf2 were also detected in the tongue and oral epithelia, rib bone undergoing ossification and in the medullar region of thymus.
在表皮分化过程中，细胞内和细胞外钙（Ca++）浓度诱导一系列信号通路。角质形成细胞遵循复杂的钙依赖性分化程序，从基底增殖层开始，经过棘状和颗粒状分化层，最终形成表皮的角质层。钙结合蛋白家族成员在钙信号转导中起核心作用。利用抑制性消减杂交筛选比较基底和分化的角质形成细胞，我们鉴定出了新的钙结合蛋白基因Scarf（皮肤钙调蛋白相关因子）和Scarf2，它们与钙调蛋白（CaM）具有同源性。在本研究中，我们对发育中小鼠的Scarf和Scarf2转录本及蛋白的表达模式进行了全面分析。为了检测胚胎发育过程中Scarf2的表达，我们进行了原位杂交，并在毛囊、皮肤和鼻上皮中检测到了表达。这些结果与先前报道的Scarf基因表达有大量重叠[Hwang, M., Morasso, M.I., 2003. 新型小鼠钙结合蛋白Scarf在表皮分化过程中差异表达。《生物化学杂志》278, 47827 - 47833]。将新生和成年小鼠皮肤中Scarf和Scarf2蛋白的表达模式与几种表皮结构蛋白，即角蛋白14（K14）、角蛋白1（K1）、兜甲蛋白（LOR）和丝聚蛋白（FIL）进行比较，结果表明它们的表达与K1重叠，K1是角质形成细胞分化的早期标志物。有趣的是，在舌头和口腔上皮、正在骨化的肋骨以及胸腺髓质区域也检测到了Scarf和Scarf2。
