摘要
Ras主要参与表皮生长因子家族调控细胞分裂的信号通路。采用末端快速扩增法获得了牙鲆(Paralichthys olivaceus)ras-2基因全长2 384 bp cDNA序列,该序列编码187个氨基酸,含有switchⅠ、switchⅡ、P-loop、CAAX box等Ras家族的结构特征,与川鲽(Platichthys flesus)ras-2氨基酸序列相似性最高(96.3%)。定量RT-PCR检测显示ras-2基因在牙鲆成体的心脏、肝脏、脾脏、肾脏、鳃、肠、肌肉、鳍条和皮肤组织均有不同程度的表达,其中鳍条表达量最高,肌肉的表达量最低;在牙鲆变态前和变态初相对表达量较高,随着变态进行,表达水平显著降低。牙鲆变态阶段的RNA整体原位杂交结果显示ras-2基因主要在鳍条、眼眶周围、颌、鳃、鼻孔、侧线等部位的表皮组织中表达,变态前在鳍褶和体侧线表达信号最强,变态阶段E期的信号稍微减弱,主要分布在支鳍骨和鳃,变态高峰期(F期和G期)信号主要集中在支鳍骨、鳃和颌,H期表达信号主要集中在鳃和支鳍骨。ras-2基因表达式型表明其可以通过调控细胞分裂的方式,参与牙鲆变态过程中眼睛移动、冠状幼鳍发育、侧线发育等多种器官的发育调控。
Ras is mainly involved in the epidermal growth factor family regulating the signaling pathway of cell proliferation. To investigate the relationship between ras-2 expression and metamorphosis in Paralichthys olivaceus, the full-length cDNA of ras-2 gene with 2 384 bp was obtained by rapid amplification of cDNA ends （RACE）. The ras-2 gene encodes 187 amino acids with typical structure such as switch I , switch Ⅱ , P-loop and CAAX box, sharing 96. 3% sequence similarity with another flatfish Platichthys flesus revealed that ras-2 gene was expressed universally in adult P. olivaceus. The highest expression of found in the fin, while the lowest expression in the muscle. During metamophosis of P RT-qPCR ras-2 was olivaceus, expressional level of ras-2 gene was decreasing significantly. The whole mount RNA in situ hybridization further showed the expression pattern of ras-2 during metamorphosis of P. olivaeeus and revealed its expression mainly in the epidermal tissues located in fin, jaw, orbit, nostril, lateral line and so on. Higher expression signals were observed mainly in fin, lateral line, jaw and gill during metamorphosis. Sinee Ras-MAPK pathway is well-known in regulating cell proliferation, based on expressional pattern of ras-2 gene, we postulate that ras-2 might participate in eye migration and development of lateral line, dorsal fin and gill via regulating epidermic cell proliferation during metamorphosis of P. olivaceus.
出处
《上海海洋大学学报》
CAS
CSCD
北大核心
2013年第5期641-649,共9页
Journal of Shanghai Ocean University
基金
国家自然科学基金(31072201)
