The role of miRNAs in plant development and virus defense
微型RNA是最近發現的小RNA，調控生物體內的反應，包括生長、細胞分化、對抗病毒…等。植物利用RNA干擾 (RNAi) 或過敏反應 (HR) 對抗病毒感染。有趣的是，miR168可藉由降解mRNA或抑制轉譯，調控阿拉伯芥AGO1的表達，而AGO1是RNAi的一個重要元件。miR398則調控銅鋅超氧化物歧化? (CSD1, CSD2) 的表達，而CSD1, CSD2負責產生過氧化氫去引發細胞凋亡 (cell apoptosis)。帶有竹嵌紋病毒 (BaMV) 全長基因的轉殖菸草 (Nicotiana benthamiana) 品系27-17是我們的研究材料。27-17的幼葉不具病徵，隨著葉子的生長，病徵會漸漸變嚴重。我發現被病毒感染時，植物會提高AGO1的表達，使RNAi更有效率。然而，病毒藉提高miR168使AGO1的量無法上升。植物亦可提高CSD1, 2 mRNA的量，促進細胞凋亡。病毒卻會引發miR398降解CSD2 mRNA。在病毒力價高的葉子中，雖然CSD2 mRNA降低且miR398升高，植物仍可大量提高CSD2蛋白的量。CSD1 mRNA沒有被miR398負調控，詳細原因仍有待研究。
姑婆芋的傳粉生物學
我們在校園內設置兩樣區，從2007 年4 月至2007年6月，共調查9株姑婆芋，93朵佛焰花，以瞭解姑婆芋生活史、傳粉昆蟲生活史及兩者之間的互動關係。 姑婆芋在11 月至7 月花期時會不斷產生佛焰花苞，剛冒出的花苞經過1到3天後，雌蕊漸成熟，佛焰苞會漸漸展開，開始產熱及一些特殊氣味，吸引果蠅科未知種的蠅類傳粉。當胚株受粉後，佛焰苞頸部會閉合，迫使傳粉昆蟲會往上爬到雄蕊部位攜帶花粉，飛至另一株姑婆芋雌蕊上傳粉，因此姑婆芋與傳粉昆蟲之間具有互利共生的關係。佛焰花序主要產生氣味的部位是在附屬物及雄部，而佛焰苞則可以幫助吸引更多傳粉昆蟲。佛焰花序的附屬物及雄部相對溫度較高，可能具有產熱以吸引傳粉昆蟲的功能。 ;Our study started from April, 2007 to June, 2007. We observed a total of 9 Alocasia odora and 93 spathes to help understand the life cycle of these understory clonal herbs, its pollinators, and the relationship between them. Alocasia odora produces spathes continuously during inflorescence. In the female phase, the pistillate part of the inflorescence ripens and an opening appears at the spathe, heat and a special odor is produced to attract pollinators of Drosophilidae. When the ovule is pollinated, the male phase begins and the opening encloses, which forces the pollinators upwards to the staminate part to carry its pollens, and then fly to an other Alocasia odora, Heat and the special odor are produced by the appendix and the staminate part of the inflorescence, and the spathe can increase the number of pollinators attracted. The relationship of mutualism between these two species contribute to the study of coevolution.
稀子蕨的生殖策略探討
稀子蕨（Monachosorum henryi Christ）生長在台灣中海拔山區，是少數具有特殊生殖方式(不定芽)的蕨類。本研究對東眼山的稀子蕨族群進行物候調查，以了解其進行孢子繁殖及不定芽繁殖的過程，並試圖探討稀子蕨的不定芽是否可增加其族群對環境的適應性。研究結果顯示稀子蕨的孢子體及原葉體都無法在乾旱的環境下生存，常有大規模乾死的現象；而其不定芽則具有很強的耐旱性，無論是在季節普遍性及幼苖發育程度上，生殖芽都比孢子繁殖較佔優勢。而且其不定芽於旱季結束後，可迅速萌發，長出的孢子葉可隨之進行有性(孢子)及無性(不定芽)生殖，使其族群不至於在旱季中有地區性滅絕之虞。;Monachosorum henryi Christ , which exists in the middle elevations of the mountainous regions of Taiwan, is a fern with a special reproductive system seldom found in other ferns.This study investigates the phenology of Monachosorum henryi population in the Don Yang mountain region. Its purpose is to understand the sexual and asexual reproductive cycles of these ferns and to interpret whether or not the buds can increase the fitness of their population during the dry season.The results show that it is extremely difficult for the sporophyte and prothallus of Monachosorum henryi to survive in a drought. However, the buds have a much stronger drought endurance. According to this investigation, the adventitious buds of Monachosorum henryi are superior to the spores in seedling development in every season. Adventitious buds are able to germinate soon after the dry season as well as in any other season, and are able to grow spores and buds on their fronds enabling both a sexual and asexual way of proliferation. In this way the fern avoids a district extinction of their population.
台灣水生食蟲植物~ 絲葉狸藻捕蟲行為及消化功能的進階探索
The “Insectivorous Plants”﹐ the first historical publication by Charles Darwin﹐contained the detailed observations and meticulous descriptions of various carnivorous plants and had become the most important reference for the study of carnivorous plants﹒ But the prey mechanism and digestive function of the bladder traps of the Utricularia were not well described﹒ The present study has a great success in these fields which include the volume change of bladder traps before and after firing﹐the spontaneous pressure relief of the bladder traps even without being triggered by prey, and the quadriceps visible absorption process﹒ The last two findings are not yet publicated. This laboratory experiment is carried out with Utricularia Gibba﹐a native species of Utricularia in Taiwan﹒ Through static and dynamic observation﹐we find that bladder traps suck in water by 12-25% of body volume change, and the bladder traps release internal pressure spontaneously under long period of waiting, despite not being triggered﹒ We can also easily demonstrate the absorption process of quadriceps by manually triggering the bladder traps to suck food color solutions. All the events above can be clearly seen under microscopy﹒達爾文是最先對食蟲植物作深入且完整研究的科學家，至今他的著作仍是研究食蟲植物的重要資料，但在其內容中對狸藻捕蟲囊捕蟲行為及消化功能的研究觀察並不完整。本實驗使用簡單的方法，在這方面有突破性的進展，包括捕蟲囊捕食前後的體積變化，自發性舒張及囊內腺毛對於食用色素的消化吸收，後兩項發現及實驗均未曾出現在文獻資料中。 本實驗以台灣本土水生食蟲植物絲葉狸藻(Utricularia gibba)為研究對象，由靜態及動態觀察，顯示捕蟲囊捕食前後體積變化為12~25%，且即使在沒有捕到水中生物的情況下，也會有自發性舒張以解除囊內壓力的現象。捕蟲囊內四爪腺毛消化吸收功能的整個過程，可藉由食用色素加以呈現，並清楚的在顯微鏡下觀察到這些現象。
台北市內湖區金面山地衣調查與空氣污染對地衣影響之探究
本研究工作自2001 年7 月至2002 年6 月止，在臺北市內湖區金面山進行地衣實地探勘採集調查，以位於臺北市內湖區之麗山高級中學之校園為中心點，範圍由校園金面山至學校前門所面對的港墘路與環山路口。應用「外部型態比較」，「切片觀察(徒手切片技術)」與「化學分析(薄層色層分析Thin Layer Chromatography, TLC)」等三種方法，鑑定所採集之地衣所屬種類，並探討空氣污染程度對金面山地衣類分佈狀況的影響。調查至2002年6月為止，本研究已發現生長於金面山區之數種地衣，其中殼狀地衣包含有：癩屑衣屬(Lepraria)、球粉衣屬(Spheophorus)、大孢衣屬(Megalospora)等三屬；屬於莖狀地衣的僅有石蕊屬(Cladonia)；為葉狀地衣的則有：黃梅衣屬(Xanthoparmelia)、裸緣梅衣屬(Parmotrema)、梅衣屬(Parmelia)等三屬，合計共七個屬。本研究針對臺北市金面山區及麗山高級中學之校園附近市區道路地衣類分佈的情形做調查，結果發現行道樹上之附生地衣在較靠近山區的地方，於樹幹上的生長覆蓋面積才會有明顯增加的情形，又其中在市區道路上只發現殼狀地衣生長，而莖狀及葉狀地衣則出現於金面山頂附近，所以就此情況而言，除了金面山區外，市區已呈現地衣沙漠化之狀況，間接顯示，市區的空氣污染是相當嚴重的。本研究將所調查結果之各屬地衣類進行特徵描述與分佈地區之標定，以便於日後臺北市內湖區金面山地衣之鑑識及後續相關研究之進行。This research was carried out between July 2001 and June 2002 on the Jinmian Mountain in Neihu,\r Taipei City and consisted of an on-the-spot exploration and collection of lichen. The Taipei Municipal\r Lishan High School was the center of this research, and the researched territory consisted of the areas\r between the mountain at the back of the school (Jinmian Mountain) and the intersection between\r Gangcian Rd. and Huanshan Rd. in front of the school’s main gate. Comparison of external appearance,\r dissectional observation (manual breaking technique), and chemical analysis (Thin Layer\r Chromatography, TLC) were the research methods applied to determine the genus of the lichen and the\r influence of the degree of air pollution on the distribution of the lichen.\r By the end of the research in June 2002 the presence of three types of lichen on the Jinmian\r Mountain was observed: crustose lichen: Lepraria, Spheophorus, Megalospora; fruticose lichen: Cladonia;\r foliose lichen: Xanthoparmelia, Parmotrema, Parmelia. Seven different genus of lichen have been found.\r The research has been done on the distribution of these different genus of lichen in the area of the\r Jinmian Mountain and The Taipei Municipal Lishan High School: By observation the sidewalk trees\r near the mountain’s area, we found the covering area of the lichen on the sterns apparently increases,\r while on the trees in the city district, only crustose lichen grow. The fruticose and foliose lichen only\r grow near the top of the Jinmian Mountain. This impoverishment of the diversity of lichen in the city\r district might (indirectly) be an indicator of the considerable decline of air quality in the city. The\r outcomes of this research regarding the description and distribution of the lichens contribute to the\r knowledge on lichens in the Jingmian Mountain area in the Neihu District, and may raise the similar\r research in the future as well.
野外實測嗜酸性溫泉紅藻光合作用能力之特性
台灣溫泉資源豐富，不同的溫泉泉質適合不同的溫泉藻類生長。溫泉藻屬於極端生物，其應用資源極待研究開發。本研究根據細胞型態、藻膽蛋白種類分析以及rbcL 基因定序等結果推測北投溫泉藻屬於一種溫泉紅藻，其種類近似於Galdieria sp. (Rhodophyta)。此外，本研究利用葉綠素螢光分析儀於野外實測北投溫泉紅藻於不同光強度下，光合作用能力的差異，發現適應於不同光強度的溫泉紅藻，其電子傳遞速率並無顯著的差異。推測其原因可能與北投溫泉紅藻的phycocyanin 含量會隨著光量有所調整，藉此達到最佳的光合作用能力有關。另外，本研究發現隨著光強度的上升，溫泉藻的NPQ 值有上升的趨勢，然而低光區的溫泉藻有較高的NPQ 值，此與一般理論不符。利用HPLC 分析北投溫泉紅藻的類胡蘿蔔素種類組成，其種類分別為Lutein、α-carotein、β-carotein 與Zeaxanthin，未發現Violanxanthin 與Antheraxanthin，北投溫泉紅藻並不俱有葉黃素迴圈。因此根據研究結果，我們認為NPQ 值與色素的關係仍有討論的空間Taiwan is resourceful in hot springs. Various hot spring algae are adapted to different types of hot springs. Hot spring algae applications are still under developing. In this work, based upon the morphology, analysis of phycobiliproteins, and rbcL sequences, the hot spring algae of Peitou is found to be Galdieria maxima (Rhodophyta). In addition, the dependence of the photosynthesis of Galdieria maxima on the light intensity was measured by Diving-PAM. The results show that the light energy availability efficiency of Galdieria maxima adapting to different light intensity exhibited different, although the electron circulate rate differed insignificantly. This suggests that the concentration of phycocyanin in Galdieria maxima may vary to attain optimal photosynthesis. Furthermore, the NPQ of Galdieria maxima increase with the light intensity. However, contradict to the theory; even under the same light intensity, the NPQ of Galdieria maxima was higher at low light zone. The carotene composition of Galdieria maxima was analyzed using HPLC and found lutein, α-carotene, β-carotene, and zeaxanthin. Violaxanthin and antheraxanthin were not present. Therefore, Galdieria maxima do not exhibit xanthophyll. Based on the results of this study, the correlation between NPQ and pigment still needs to be investigated.
日長處理對大豆蛋白質合成的影響
日照影響花芽分化及生長試植物生理學上的重要課題,根據相關文獻指出,蛋白質類型的變化是影響開化的重要關鍵,大豆是短日照植物,分別以長日照(LD18hr/DAY)和短日照(SD6hr/DAY)處理,抽取葉片中的蛋白質以SDS-PAGE.2D-SDS-PAGE分析,SDS-PAGE的實驗姐果顯示出在分子量25.2 32.9 38.6 20.6 64.0 100.6 kDa處中的蛋白質SD比LD的量多,但是在分子量16.8kDa以下的蛋白質LD含有高濃度而自SD只有一點,我們使用2D-SDS-PAGE做進一步的分析,SD與LD分為三個區塊討論(SD1-3 LD1-3)有許多蛋白自LD1.LD3出現,但在SD1 SD3中未出現,可能有抑制花芽分化的作用,而在SD2中有多個高濃度蛋白出現,可能在花芽分化上扮演重角色,其中編號P1 P2的蛋白質有較明顯的變化,根據NCBI網站上的資料顯示,P1蛋白質與光敏素C有關,而P2蛋白質則沒有找到分子量等電點類似的蛋白質;The effects of photoeriod on floral initation and develoment is an imporant phyiological subject and have studed ve he past 70 years. Accrding to the reference, polypeptide partten plays an important rolein photoperiodic induction. Soybean s a SD(short day)plant. So we planted them with 6-h(short day,SD)and 18-h(long day,LD)photoperiods. Total proteins n leaves of soyban were extracted from the vegetable,SD and LD. And using SDS-PAGE and 2-D eloctrophoresis to analyze. 25.2,32.9,38.6,50.6,64.0,and 100.6kDa polypeptides in SDS-PAGE were always present in leavess at SD but only a little bands f the polypeptides appeared at LD. And many polypeptides whose molecular weight(Mw)is below 16.8 kDa had higher concentration at LD ad Reduced at SD. We found three different areas(SD1~3,LD1~3) and analyze them. Many proteins were found n LD1,LD3 and reduced in SD2,SD5. Possibly, these polypeptides found in LD1 and LD3 play an important role in restraining floral iniiation in soybean. Many proeins had more concentration in SD2. Probably, they play an important role in photoperiodic induction and floral initiation. We found a protein labeled P1 in SD2 and it is with molecular weight(Mw) of 36kDa at isoelectric point(pI) of5.2, and it may be related to cytochromeC. We also found protein labeled P2 in SD2 and it is with molecular weight(Mw) of 40.2kDa at isoelectric point(pI)of 5.4, and we couldn't find any protein that has the similary Mw and pI in potein database about flowering and daylength.
The Flying Chloroplasts Drug Test
Previously, I studied the acute effects of a common broadleaf herbicide, Killex (by Montsano) and a pesticide, Spidercide (by Wilson), on cytoplasmic streaming in detached leaves from the pond weed, Elodea canadensis. I found that Killex, active ingredient 2-4D, an auxin analog, applied at the recommended dose decreased the rate of cytoplasmic streaming by 64% over a 20 minute observational period. The Spidercide, active ingredient d-trans allethrin, a Na+ channel activator, stopped cytoplasmic streaming after a 5 minute exposure and no recovery was observed during the 20 minute observational period.