Motoyama J, Heng H, Crackower M A, Takabatake T, Takeshima K, Tsui L C, Hui C
Program in Developmental Biology, Research Institute, The Hospital for Sick Children, 555 University Avenue, Toronto, Ont. M5G 1X8, Canada.
Mech Dev. 1998 Nov;78(1-2):81-4. doi: 10.1016/s0925-4773(98)00149-x.
In Drosophila, patched encodes a negative regulator of Hedgehog signaling. Biochemical experiments have demonstrated that vertebrate patched homologues might function as a Sonic hedgehog (Shh) receptor. In mice, two patched homologues, Ptch and Ptch2, have been identified. Sequence comparison have suggested that they might possess distinct properties in Shh signaling. In the developing tooth, hair and whisker, Shh and Ptch2 are co-expressed in the epithelium while Ptch is strongly expressed in the mesenchymal cells. We report here the chromosomal localization of Ptch2 and further analysis of Ptch2 expression. Throughout mouse development, the level of Ptch2 expression is significantly lower than that of Ptch. In early mouse embryos, Ptch and Ptch2 were found to be co-expressed in regions adjacent to Shh-expressing cells in the developing CNS. Similar to other epidermal structures, Shh and Ptch2 also show overlapping expression in the developing nasal gland and eyelids. Thus, during mouse development, Ptch2 is expressed in both Shh-producing and -nonproducing cells.
在果蝇中，patched编码一种Hedgehog信号通路的负调控因子。生化实验表明，脊椎动物patched同源物可能作为音猬因子（Shh）的受体发挥作用。在小鼠中，已鉴定出两种patched同源物，即Ptch和Ptch2。序列比较表明，它们在Shh信号通路中可能具有不同的特性。在发育中的牙齿、毛发和触须中，Shh和Ptch2在上皮细胞中共表达，而Ptch在间充质细胞中强烈表达。我们在此报告Ptch2的染色体定位以及对Ptch2表达的进一步分析。在整个小鼠发育过程中，Ptch2的表达水平明显低于Ptch。在早期小鼠胚胎中，发现Ptch和Ptch2在发育中的中枢神经系统中与表达Shh的细胞相邻的区域中共表达。与其他表皮结构类似，Shh和Ptch2在发育中的鼻腺和眼睑中也表现出重叠表达。因此，在小鼠发育过程中，Ptch2在产生Shh和不产生Shh的细胞中均有表达。
