Wang Na, Sun Yong-Hua, Liu Jing, Wang Ya-Ping, Zhu Zuo-Yan
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
Dev Genes Evol. 2007 Apr;217(4):299-305. doi: 10.1007/s00427-007-0139-2. Epub 2007 Feb 23.
Sonic hedgehog (Shh), one of important homologous members of the hedgehog (Hh) family in vertebrates, encodes a signaling molecule that is involved in short- or long-range patterning processes during embryogenesis. In zebrafish, maternal activity of Hh was found to be contributing to the formation of primary motoneurons. However, we found that all of the known Hh members were not maternally expressed in zebrafish. In the present study, full-length cDNA of common carp (Cyprinus carpio) Shh (cShh) was gained by degenerate reverse-transcription PCR (RT-PCR) and rapid amplification of cDNA ends. Sequence comparison shows that cShh coding sequence shares 93.4% identity with zebrafish Shh coding sequence, and their corresponding protein sequences have 91.9% similarity. Comparative analysis of Shh genomic sequences and Hh protein sequences from different species revealed that the genomic structures of Hh are conserved from invertebrate to vertebrate. In contrast to zebrafish Shh, cShh transcripts were detectable from one-cell stage by RT-PCR analysis. Whole mount in situ hybridization verified the maternal expression of Shh in common carp, which is, to our knowledge, the first report of that in vertebrates, suggesting that Shh might be responsible for the maternal Hh activity in common carp.
音猬因子（Shh）是脊椎动物中刺猬因子（Hh）家族重要的同源成员之一，它编码一种信号分子，参与胚胎发育过程中的短程或长程模式形成过程。在斑马鱼中，已发现Hh的母源活性有助于初级运动神经元的形成。然而，我们发现所有已知的Hh成员在斑马鱼中都没有母源表达。在本研究中，通过简并逆转录PCR（RT-PCR）和cDNA末端快速扩增获得了鲤鱼（Cyprinus carpio）Shh（cShh）的全长cDNA。序列比较显示，cShh编码序列与斑马鱼Shh编码序列的同一性为93.4%，它们相应的蛋白质序列相似度为91.9%。对不同物种的Shh基因组序列和Hh蛋白质序列进行比较分析发现，Hh的基因组结构从无脊椎动物到脊椎动物都是保守的。与斑马鱼Shh不同，通过RT-PCR分析在单细胞阶段就能检测到cShh转录本。整体原位杂交证实了鲤鱼中Shh的母源表达，据我们所知，这是脊椎动物中关于此现象的首次报道，表明Shh可能是鲤鱼母源Hh活性的原因。
