tski基因在?郭魚（Oreochromis aura）各發生階段mRNA的分佈表現

Abstract

v-ski感染鳥類胚胎纖維母細胞(quail embryo fibroblast)時，會使細胞轉型，但感染鳥類胚胎體壁細胞(quail embryo body wall cell)，反而分化為骨骼肌。c-ski為v-ski的原型致癌基因(proto-oncogene)，其蛋白質為一轉錄因數，具體的生化及生理功能仍在探索的階段。 吳郭魚Oreochromis aurea的c-ski有兩種types：tski1及tski2。在成魚器官組織有不同程度及形態的tski表現：其中腦部表現量最高，而骨骼肌最少；在胚胎發生階段亦有不同的表現。 In situ hybridization分析吳郭魚成魚的平滑肌、心肌、骨骼肌，發現tski1及tski2在平滑肌中(腸、胃)不表現，在心肌、骨骼肌表現量亦偏低，且非均勻表現，而tski2的表現量略高於tski1；另外tski1及tski2在腸、胃平滑肌中雖不表現，但在黏膜(mucosa)卻有高度的表現。在腦部皮質處(cortex)的顆粒層(granular layer)有tski1及tski2的高度表現。胚胎發生第17階段(嘴巴可張開、鰓形成),tski1及tski2在腦部皮質層有明顯的表現；肌管(myotube)、肌纖維、鰓軟骨、發生階段軟骨內骨(endochondral bone)的軟骨、神經視網膜亦有表現，且tski1在肌纖維表現較tski2高。在fry階段(卵黃囊完全被吸收、可自由遊動、消化系統完成發育、並開始進食)，除了腦、神經視網膜，有tski1及tski2的明顯表現，腹部的白肌(white muscle)、腸、胃亦出現大量表現。

Overexpression of v-ski, or its proto-oncogene, c-ski, has an effect on proliferation, morphological transformation and myogemc differentiation in fibroblast culture and transgenic animal. As a transcription factor, the biological role of c-Ski depends on the cellular environment and is under deciphering. Two types of c-ski, tski1 and tski2, have been identified in tilapia, Oreochromis aurea. tski transcripts are widely expressed in different adult tissues and developmental stage embryos. The most and the least abundant tski transcripts are located in the brain and skeleton muscle, respectively. In situ hybridization analyzes the different type of adult tilapia muscles, revealing little expression of tski transcripts in the smooth muscle of intestine and stomach, heart muscle and skeleton muscle. However, tski2 transcripts are more abundant than tskil transcripts in heart and skeleton muscle fiber. Meanwhile, tski transcripts are expressed in the mucosa of intestine and stomach. The gill filament and cortex of cerebrum express abundant tski. The cortex of brain expresses abundant tski transcripts in the stage 17 embryo (mouth opening and gill formation). The myotube, embryo muscle fiber (superficial red muscle and inner white muscle), cartilage in the gill arch and in the developing endochondral bone, and neuroretina also have the expression of tski transcripts. Meanwhile tski1 transcripts are more abundant in muscle fibers than tski2 transcripts. The fry (active swimming and feeding) tissues express high degree of tski transcripts in the cortex of brain, neuroretina. The intestine and stomach also express high tski transcripts, when the digestive system of fry is well developed.