2012-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/648625摘要：Ficus pumila L.是一種雌雄異株的常綠榕果植物，原生於東南亞並具有許多變種。其中有兩型變種在臺灣有分佈，分別為薜荔 (F. pumila var. pumila, creeping fig) 和愛玉 (F.pumila var. awkeotsang, jelly fig)。薜荔廣泛分佈於臺灣本島低於海拔500 公尺的地方，而愛玉原生於臺灣僅分佈於海拔 800-1800 公尺之間的山區。由於這兩型的榕果和其授粉蜂Wiebesia pumilae 分布在不同的棲地，提供了一個研究植物和授粉蜂之間的遺傳互作和氣候改變對遺傳結構的影響好的機會。因為生活於較高的海拔，愛玉小蜂相對於薜荔小蜂必須面對低溫。此外，愛玉相對於薜荔有較長的隱花果週期，表示愛玉小蜂相對於薜荔小蜂有較長的幼蟲期與壽命。以上的特化需要調整粒腺體中的電子傳遞鏈，以改進細胞產生能量的方式。而我們初步的結果發現愛玉小蜂粒線體細胞色素氧化酶次單元I (mitochondrial cytochrome c oxidase I subunit, mtCOI)的胺基酸改變有加速演化的現象，可能是為了適應寒冷的環境所作的改變。本研究的目的在瞭解授粉蜂和其寄主榕果之間複雜交互作用的遺傳結果。將分析小蜂參與電子傳遞鏈的基因，包括粒線體與核基因。此外，也將分析授粉蜂與榕果的核微衛星基因型。我們的目的是 (1) 估算愛玉和薜荔之間、愛玉小蜂和薜荔小蜂之間的分化時間與分化程度，(2) 確認促使族群分化的可能因子，(3) 研究當棲地變換時電子傳遞鏈重組的機制。<br> Abstract: Figs (Moraceae: Ficus) and their pollinating wasps (Hymenoptera: Agaonidae) constitutethe most tightly integrated and specialized case of obligate mutualism known. Because ofstrong interactions between the life histories of host figs and pollinating wasps, it isreasonable to expect that their genetic structures and population demographics would behighly associated. For example, due to the limited dispersal ability of fig wasps,environmentally isolated fig plants may facilitate the differentiation of wasp populations. Ifthe isolation persists long enough, different wasp populations may be locally adapted whichmay, in turn, promote the divergence of their fig hosts.Regarding the above description, two types of Ficus pumila L. and their pollinatingwasps, Wiebesia pumilae, found in different habitats of Taiwan provide a good opportunity tostudy genetic interactions between host figs and their pollinating wasps and the influences ofclimatic changes on their genetic structures. Ficus pumila is a dioecious evergreen fig nativeto Southeast Asia with many varieties. Among them, two varieties, namely F. pumila var.pumila (creeping fig) and F. pumila var. awkeotsang (jelly fig), are found in Taiwan. Thecreeping fig is native to southeastern China through Malaysia and is widely distributedthroughout the main island of Taiwan below 500 m in elevation. On the other hand, the jellyfig is native to Taiwan and can only be found in mountain areas at 800~1800 m in elevation.Because of living at higher elevations, pollinators of the jelly fig have to face coldertemperatures than pollinators of the creeping fig. In addition, the longer syconium cycle of thejelly fig than that of the creeping fig indicates that the jelly-fig wasps have longer larvaldevelopment and lifespan than creeping-fig wasps. The adaptation to cold environmentswould require jelly-fig wasps to increase their mitochondrial aerobic energy production, aswas shown in vertebrates and invertebrates. In addition, the prolonged larval development andextended lifespan of jelly-fig wasps may require their energy-generating machinery to provide"clean" energy in terms of minimized reactive oxygen species (ROS) production. All of theabove need a remolding of the electronic transport chain (ETC). Our preliminary resultsdemonstrated an accelerated amino acid divergence in mitochondrial cytochrome c oxidase Isubunit (mtCOI) between creeping- and jelly-fig wasps, suggesting that it may have alteredmitochondria energy production to accommodate increased energy demands resulting fromcold adaptation.To further address this question and to reveal the genetic consequences of complexinteraction between pollinating wasps and their host figs, we aim to sequence genes involvedin ETC complex, including both mitochondrial and nuclear genes, from pollinating wasps. Inaddition, nuclear microsatellite loci from wasps and figs, respectively, will be genotyped. Ourgoals are to (1) estimate the timing and magnitude of differentiation between creeping andjelly figs and their pollinators, (2) identify potential factor(s) that drive divergence betweenpopulations, and (3) study the mechanism of ETC remodeling during habitat shift.