李士傑臺灣大學:漁業科學研究所朱啟璟Ju, Chi-ChingChi-ChingJu2007-11-282018-07-062007-11-282018-07-062004http://ntur.lib.ntu.edu.tw//handle/246246/59314本研究主要利用減差基因選殖的技術篩選出吳郭魚早期性別分化關鍵時期可受性類固醇激素所調控的基因群,進一步分析其位於組織內之表現情形,期望可找到可專一地表現在精、卵巢的基因,以暸解這些基因跟魚類性別分化機制之關係。我們使用莫三比克吳郭魚(Oreochromis mossambicus)為實驗動物,在取得口孵仔魚之後,將仔魚分成三群,分別餵食添加甲基睪固酮(17?methyltestosterone, MT)、餵食添加雌二醇(17β-estradiol, E2)飼料或無添加任何激素飼料,而得到較高雌雄比之仔魚群,以提供進行減差基因選殖實驗。結果顯示因MT處理而增加表現的已知基因有八個,受MT處理降低表現的已知基因有六個,受E2刺激增加表現的已知基因有兩個,受E2刺激而降低表現的已知基因有一個。由其中先挑選可因MT處理而增加表現的基因transferrin和parvalbumin來進一步分析其在組織中之表現,我們發現transferrin主要表現在成魚肝臟中,其次是在眼睛、腦、心臟,而在卵巢中則有鴩B選殖出一段較長之transferrin片段,認為它是屬於粒腺體中之transferrin前驅物;而parvalbumin在肌肉中表現較多,其次是腦和表皮組織,其序列相似高。利用原位雜合技術進一步地分析transferrin和parvalbumin在組織中之表現情形,發現parvalbumin會在大腦內側之海馬迴區域及肌肉中的肌質網有表現;transferrin則是會在腦室間連結之脈絡叢上表現。未來,將繼續尋找可專一性表現在生殖組織內且又可受性類固醇激素表現的基因群,藉以探討魚類性別分化的複雜分子機制;另外,繼續探討MT在仔魚早期促使parvalbumin和transferrin表現量增加所代表之特殊生理意義。The development and growth of sex organs is mainly mediated by sex hormones, including estrogen and testosterone, which govern the female and male development, respectively. Exogenous sex steroids have a remarkable influence on phenotypic sex. It is well demonstrated that the exogenous steroids affect sex differentiation in developing fry(Baroiller et al., 1999). However, the changes in gene expression upon sex hormone treatments in fry are less clear. To approach this question, we examine the changes in gene expression pattern in fry of tilapia, Oreochromis mossambicus, under the influences of exogenous steroids, 17?methyltestosterone (MT) and 17β- estradiol(E2). Mozambique tilapia is an excellent model for studying steroidogenic actions during gonadal sex differentiation since the sex can be altered by sex hormones irregardless of its genetic sex. Therefore, we had adapted a method from Tsai et al. (2000) to prepare all male or all female tilapia. We then performed PCR subtracted hybridization on those homo-sex fry and identified some sex steroid-induced differentially expressed genes in developing tilapia fry. Among those genes, we found parvalbumin and transferrin were up-regulated by MT during sex-sensitive periods in tilapia. We have cloned the full open reading frame of parvalbumin. Parvalbumin expressed in brain, muscle and skin as tissue-specific isoforms, respectively. From their amino acid sequences, we suggest that one or two amino acid shift could decrease the sequence similarity of calcium-binding motif. We have also cloned a transferrin with partial sequence. Transferrin expressed in liver, heart, eye and brain. We also have cloned a longer transferrin fragment(753 bp)in the ovary. The up-regulation of parvalbumin by MT were confirmed by quantitative-PCR. Using in-situ hybridization, we found that parvalbumin was expressed in the hippocampus and sarcoplasmic reticulum, and transferrin was expressed in the brain choroids plexus. The significance of up-regulation of parvalbumin and transferrin by MT is still under investigation.目錄………………………………………………………………………………I 表目錄……………………………………………………………………………V 圖目錄………………………………………………………………………………VI 摘要……………………………………………………………………………VII Abstract…………………………………………………………………………IX 一. 前言………………………………………………………………………………1 1. 魚類性別改變與性類固醇激素之應用……………………………………2 2. 性類固醇激素(sex hormone)之生理功能與研究…………………………3 2.1 雄性素(androgen)的功能與作用機制…………………………………3 2.2 雌性素(estrogen)的功能與作用機制…………………………………5 3. 快速大量分析(High Throughput Analysis)基因表現差異之技術…7 表達序列標籤(EST)………………………………………………………8 互補DNA(cDNA)微陣列矩陣晶片………………………………………8 減差雜合基因選殖(Subtractive Hybridization Cloning)………………9 RNA指紋鑑定技術(RNA fingerprinting)…………………………………10 基因表達系列分析(Serial Analysis of Gene Expression, SAGE)…10 5.研究的具體目標………………………………………………………………11 二. 材料與方法……………………………………………………………………12 1. 實驗動物……………………………………………………………………12 2. 性類固醇激素處理實驗……………………………………………………12 3. 核糖核酸之萃取(Total RNA extraction)…………………………………13 4. PCR減差雜合反應:(PCR-based subtractive hybridization)………14 4.1 訊息核醣核酸之純化(mRNA purification)…………………………14 4.2 第一股互補DNA的合成(1st cDNA synthesis)…………………………15 4.3 第二股互補DNA的合成(2nd cDNA synthesis)..………………………15 4.4 Rsa I限制酵素切割DNA片段(RsaI digestion)…………………………16 4.5 Adapter的黏合(adapter ligation)…………………………………………17 4.6 第一次雜合反應(1st hybridization)……………………………………17 4.7 第二次雜合反應(2nd hybridization)……………………………………18 4.8 PCR放大差異基因片段(PCR amplification)……………………………18 4.9 接合和轉化反應(Ligation and Transformation)……………………19 4.10 快速篩選菌落法(Colony PCR)………………………………………20 5. 石蠟包埋原位雜合實驗……………………………………………………20 5.1 石蠟包埋切片(paraffin-embedded section)……………………………20 5.2 DIG標定核酸探針製備(DIG labeled probe synthesis)………22 5.3 原位雜合反應(In Situ Hybridization )……………………………23 6. 序列比對和演化樹分析(multiple sequence alignment and phylogenetic tree analysis)…………………………………………………………………………25 7. 即時定量PCR(Real-Time Quantitative PCR)……………….………………25 8. 定序分析(sequence analysis)……………………………….……………26 三.實驗設計流程圖…………………………………………………………………27 四.結果………………………………………………………………………………28 性類固醇激素處理影響性別分化期間吳郭魚仔魚之基因表現………………28 Parvalbumin(pvalb)基因之分析…………………………………………29 (1)成魚組織中基因表現分析…………………………………………………29 (2)肌肉、腦部及表皮組織Pvalb基因序列之選殖與序列分析……………30 (3)Pvalb基因二級結構的預測………………………………………………30 (4)吳郭魚與其他物種pvalb蛋白質序列之比較……………………………30 (5)吳郭魚pvalb基因演化親緣關係分析……………………………………31 Transferrin(Tf)基因之表現分析…………………………………………32 (1)成魚組織中基因表現分析………………………………………………32 (2)吳郭魚不同長度Tf基因片段的比對………………………………………32 (3)Tf替代性剪接(alternative splicing)基因片段選殖………………….….33 利用原位雜合技術探討Tf和pvalb基因mRNA在組織中之表現……………33 五.討論………………………………………………………………………………35 Pvalb與性類固醇激素之間的關係…………………………………………36 Tf與性類固醇激素之間的關係…………………………………………………37 性類固醇激素對下游基因之影響………………………………………………39 性類固醇激素之使用……………………………………………………………40 未來之研究方向……………….………………………………………………41 六.參考文獻………………………………………………………………………43 七.表………………………………………………………………………………53 八.圖………………………………………………………………………………60 附錄A:儀器與試劑…………………………………………………………………71 附錄 B:引子序列………………...…………………………………………………76 表 目 錄 頁數 表一.吳郭魚仔魚飼料配方……….……………………………………53 表二.Characterization of colonies resulted from PCR-based subtractive hybridization………………………………………………..…54 表三.Insert size determination of colonies resulted from PCR-based subtractive hybridization………………………………...……...55 表四.MT刺激後表現量增加的基因(MT+)………………..………56 表五.MT刺激後表現量降低的基因(MT-)……………….………57 表六.E2刺激後表現量增加之基因(E2+)…………………….…58 表七.E2刺激後表現量降低之基因(E2-)……………….………59 圖 目 錄 頁數 圖一.吳郭魚仔魚餵食性類固醇激素飼料流程圖……………………60 圖二.MT及E2處理增加parvalbumin基因之表現……………………61 圖三.Parvalbumin(pvalb)和transferrin(Tf)基因在成魚各組織中之表現分析…………………………………………………………62 圖四.吳郭魚parvalbumin基因(pvalb-1)之序列………………………63 圖五.吳郭魚肌肉、腦及表皮組織parvalbumin胺基酸序列比對…64 圖六.吳郭魚parvalbumin基因序列二級結構分析……………………65 圖七.各物種parvalbumin胺基酸序列比對分析………………………66 圖八. parvalbumin基因演化親緣關係分析……...……………………67 圖九.替代性剪接 transferrin基因片段核酸序列之比對……………68 圖十.替代性剪接transferrin基因序列之比對分析….....…………..…69 圖十一.吳郭魚parvalbumin表現在腦部海馬迴及肌肉肌質網及transferrin表現在腦室間連結的脈絡叢…………………701223183 bytesapplication/pdfen-US性別分化性類固醇激素仔魚Sex steroidal hormonessex differentiationfry性類固醇激素誘發吳郭魚仔魚基因差異性表現之探討Sex steroidal hormones induce differential gene expressions in Mozambique tilapia fry (Oreochromis mossambicus)otherhttp://ntur.lib.ntu.edu.tw/bitstream/246246/59314/1/ntu-93-R91243016-1.pdf