| DC 欄位 |
值 |
語言 |
| DC.contributor | 生命科學系 | zh_TW |
| DC.creator | 方振丞 | zh_TW |
| DC.creator | Jhen-Cheng Fang | en_US |
| dc.date.accessioned | 2011-7-29T07:39:07Z | |
| dc.date.available | 2011-7-29T07:39:07Z | |
| dc.date.issued | 2011 | |
| dc.identifier.uri | http://ir.lib.ncu.edu.tw:444/thesis/view_etd.asp?URN=982204017 | |
| dc.contributor.department | 生命科學系 | zh_TW |
| DC.description | 國立中央大學 | zh_TW |
| DC.description | National Central University | en_US |
| dc.description.abstract | mRNA降解作用為一個重要的基因表現調控機制，參與調控基因的表現，改變胞內狀態，以因應不同外在環境的變化。Poly(A) tail deadenylation為mRNA降解的速率決定步驟，而CCR4-associated factor 1s（CAF1s）在真核生物中催化deadenylation的一個主要酵素。水稻中含有四個不同的CAF1，分別為OsCAF1A、OsCAF1B、OsCAF1G、OsCAF1H。由北方墨點法與RT-PCR的分析顯示，OsCAF1s分別受到糖及不同的非生物逆境所調控。針對rOsCAF1A與rOsCAF1B重組蛋白進行胞外活性分析，結果指出其確實具有deadenylase的活性。先前的研究指出水稻受糖調控之α-澱粉降解酶的基因，αAmy3，其mRNA的半衰期會受到糖的調控。分析有糖及缺糖培養情況下之水稻細胞αAmy3 mRNA poly(A) tail長度，結果顯示在缺糖培養時其poly(A) tail長度較有糖培養長。有趣地是，在大量表現OsCAF1A轉殖水稻懸浮細胞中，發現其參與在αAmy3 mRNA的累積。由先前研究指出，OsMYBS1與OsMYBS2被證實參與αAmy3基因的表現，分別作為正向與反向的轉錄調控因子。由此分析大量表現OsCAF1A轉殖水稻懸浮細胞OsMYBS1與OsMYBS2的表現情況，結果顯示OsMYBS1表現會大量提升而OsMYBS2表現量會因此而下降。以上結果顯示OsCAF1A參與在OsMYBS1與OsMYBS2 deadenylation過程中，進而調控αAmy3 mRNA的累積。
| zh_TW |
| dc.description.abstract | One of central mechanisms to determine the expression level of genes for adjustment cellular status in response to various signals is messenger RNA (mRNA) degradation. Poly(A) tail deadenylation is a rate-limiting step of mRNA degradation. CCR4-associated factor 1s (CAF1s) is one of major enzymes to catalyze mRNA deadenylation in eukaryotes. Four members of CAF1 family, designated OsCAF1A, B, G and H, were analyzed and characterized in rice (Oryza sativa). Northern experiments and RT-PCR revealed diverse transcription patterns in response to sugar and various abiotic stresses among the four genes. Two recombinant proteins, rOsCAF1A and rOsCAF1B, had a deadenylation activity in vitro. It is known that mRNA half-life of αAmy3, which encodes a α-amylase, is regulated by sugar. Poly(A) tail analysis indicated that the length of poly(A) tail of αAmy3 mRNA was longer in the sugar-starved cells than in sugar-feasted cells. Interestingly, ectopic expression approach indicated that OsCAF1A was involved in αAmy3 mRNA accumulation. Previously, the OsMYBS1 and OsMYBS2 have been demonstrated to play a positive and negative regulator for αAmy3 expression, respectively. RT-PCR analysis indicated that ectopic expressed OsCAF1A caused the expression level of OsMYBS2 decreasing and the OsMYBS1 increasing. These results suggested that OsCAF1A may play a crucial role in mRNA deadenylation of OsMYBS1 and OsMYBS2 to regulate αAmy3 mRNA accumulation in rice.
| en_US |
| DC.subject | 糖 | zh_TW |
| DC.subject | mRNA的降解 | zh_TW |
| DC.subject | α-澱粉水解酶 | zh_TW |
| DC.subject | OsMYBS2 | en_US |
| DC.subject | OsMYBS1 | en_US |
| DC.subject | α-amylase | en_US |
| DC.subject | CCR4-associated factor 1s | en_US |
| DC.subject | mRNA deadenylation | en_US |
| DC.subject | mRNA degradation | en_US |
| DC.subject | sugar | en_US |
| DC.title | 水稻CAF1基因在水稻懸浮培養細胞之研究 | zh_TW |
| dc.language.iso | zh-TW | zh-TW |
| DC.title | Functional Analysis of OsCAF1 Genes in Rice Suspension Cells | en_US |
| DC.type | 博碩士論文 | zh_TW |
| DC.type | thesis | en_US |
| DC.publisher | National Central University | en_US |