估算土棲螞蟻聚落的新方法----以黑巨蟻(Camponotus friedae)為例
Estimated colony size is a basic work to count population of social insect up. It is not easy to measure any natural population accurately, in this respect, social insects here some advantages and some disadvantages over non-social ones. Previous studies have focused largely on the experimental colony of ants, such as Lasius niger, Myrmica sabuleti and Formica rufa, in the artificial nest. Furthermore, base on the division of labor, traditional Mark-Recapured Methods can not be used to measure complete colony of ant correcty. Here, we show that new method has be set up to calculate the colony of the ground black-giant ant, Camponotus fruedae,with a new indicator, ant hill. Predictions about the division of labor introduced to amend the formula of estimated population are discussed.本實驗探討黑巨蟻的蟻丘之形狀和生物意義,並分析利用何種方法能估算最準確的聚落大小。利用幾何圖形證明黑巨蟻會築似圓的蟻丘,並利用標識捕捉法的Petersen method(又稱為Lincoln index)、Schnabel method 和蟻丘大小重量,來推算黑巨蟻聚落之大小。發現黑巨蟻會築似圓度90%的蟻丘,而且標識捕捉法的Petersen method(又稱為Lincoln index)、Schnabel method 並不能精確的推算出黑巨蟻之聚落大小;應使用黑巨蟻之蟻丘的重量當作參數來推算,才不會忽略幼蟲的存在。
Ethidium Bromide 對p53 基因缺陷老鼠致癌影響
p53 蛋白是一種轉錄調控因子,其在抑制癌症的形成扮演很重要的角色。已知的報告顯示它能影響下游特定蛋白表現進而調控細胞週期或促使細胞進行凋亡作用。如此作用機制對於可能癌化的細胞在生物體造成傷害之前能被先行消滅,因此正常的p53 蛋白存在與否,對癌症的產生有很大的影響。 根據上述結果,我們想分析不同表現量的p53 是否對於致癌藥劑-EtBr所引發的癌化細胞有所影響。所以我們設計實驗,將具有正常表現量p53 蛋白的老鼠(p53+/+)與僅能表現少量p53 蛋白的老鼠(p53+/-),均塗以等劑量之致癌藥劑EtBr於其大腿皮膚上,觀察其致癌情形的差異。實驗結果發現 : 在塗EtBr 的14 隻p53+/-老鼠中,有3 隻出現了組織病變的症狀,包括脾臟腫大,淋巴組織長出腫瘤,而其他對照組(一)塗EtBr 的p53+/+老鼠,(二)不塗EtBr 的p53+/+老鼠或(三)不塗EtBr 的p53+/-老鼠都沒有產生異常的症狀。因此根據上述實驗結果進行推論,發現經EtBr 的刺激後,p53+/-的老鼠的確較其他的老鼠更容易得到癌化細胞。;p53 is a transcription factor that plays an important role in suppression of tumorgenesis. Previous reports showed it regulates cell cycle and enhances cell apoptosis by effecting specific proteins expression. By this way, the problematic tumor cell can be deleted to protect organism from tumor damage. According above conclusion, we are interested to know whether p53 plays a role involved the carcinogens-EtBr induced tumorgenesis. We compared the differences of tumorgenesis between mice express normal (p53+/+) or low (p53+/-) expression level of p53 proteins when they are smeared equal amount of EtBr on skin of thigh. In here, our results show three of fourteen p53+/- mice had pathological changes, containing spleen enlargement and lymphoma. However, other three comparisons, smear p53+/+ mice with EtBr (1), without EtBr (2) or p53+/- without EtBr(3), are normal. Therefore, We suggest that p53+/- mice are easily to obtain tumor than p53+/+ mice after EtBr treatment.
南爭北鬥之壁虎大戰一蝎虎與無疣蝎虎種間競爭程度之評估
無疣蝎虎(Hemidactylus bowringii)與蝎虎(Hemidactylus freuatus)分類上屬蜥蜴目守宮科蝎虎屬,為本島住家附近常見且生態地位相近的壁虎,近年來因人為因素使原本有地理區隔的兩種壁虎在北部地區產生共域現象。本研究利用問卷來調查兩種壁虎分佈狀況,並用「體型大小」、「食物競爭能力」兩種指標,設計實驗評估種間競爭程度,來探討兩種居家壁虎種間競爭程度。問卷調查及物種採集結果顯示,在台北市各行政區確實存在共域現象,且分佈數量互有消長。體型大小比較上,蝎虎體型較無疣蝎虎稍大,但在統計上無顯著差異。食物競爭能力強弱比較上,以斷尾後尾巴增長量為指標,結果兩者大致相等,無顯著差異。綜合以上研究結果,顯示兩者共域後會出現種間競爭現象,程度大致相等,有互相消長現象。Hemidactylus bowringii and Hemidactylus freuatus are commonly seen in Taiwan, and their habitats are very near the area people live. Recently, two species have inhabited the same or overlapped geographical areas in northern Taiwan. This sympatric phenomenon resulted from the geographical isolation being broken by people. This research investigated their distributions in Taipei city by using questionnaire, and evaluated the degree of interspecific competitions by using indexes of the body size comparison and the food competition to design our experiments.According to results of questionnaire and animal sampling, two geckos did inhabit closely in some areas in Taipei city, and their population distributions were changing with time. According to the result of the body size comparison, Hemidactylus freuatus is bigger than Hemidactylus bowringii. But there is not a statistically significant difference between two species. The degree of food competition of two species was all square. In summary, it was occurred the interspecific competition between Hemidactylus bowringii and Hemidactylus freuatus, and the degree of competitions was almost equal.
酒精對斑馬魚胚胎眼睛發育的影響
長期以來,臨床研究發現會影響人類胚胎的正常發育,造成胚胎畸形、成長遲緩等現象,稱為胎兒酒精症候群(fetal alcohol syndrome),但是其病理機制仍不清楚。最近的研究發現斑馬魚胚胎對於酒精有非常靈敏的反應,出現明顯的發育異常現象,例如心臟膨大、眼睛縮小、骨頭變形等現象,與人類胎兒酒精症候群相似,顯示斑馬魚非常適合作為研究胎兒酒精症候群的模式動物。在本實驗中,我們針對酒精影響視網膜神經發育的現象進行探討,並且也利用基因晶片篩選出胚胎發育時期受酒精影的的基因轉錄子,藉以了解酒雞造成胚胎畸形發育的機制。實驗結果顯示在眼睛發育過程中,1.5% 酒精浸泡會抑制視網膜神經細胞的分層(Lamination),而進一步利用RNA定位雜交的方式以眼睛的標示基因rx1、pax6b、six3b、alpha-crystallin、rho、neuroD、huC觀察他們的表現,發現酒精會減少視網膜神經細胞的分化,造成眼睛發育的缺陷。在基因晶片的分析中,我們發現酒精處理會抑制許多控制眼睛發育的基因調控子的表現,包括了crx、rybp、irx4a、optx2、rx1、brn3b1 與 vsx1等,此外約有16%的眼睛相關基因液受到酒精的抑制,遠高於其他基因受抑制的比例,顯示眼睛是酒精傷害最嚴重的區域之一。我們從實驗結果得知酒精並未對胚胎發育初期眼睛的發育造成明顯的影響,但是隨後由於控制細胞分化的幾個重要基因受到酒精抑制作用,造成視網膜神經細胞的分化停止,引起眼睛的異常發育的情況。It was known that prenatal alcohol exposure may cause serious birth defects and developmental disabilities. The molecular mechanism of this fetal alcohol syndrome still remains unclear. Here we used zebrafish embryo as a model to investigate the toxic effect of alcohol in retinal development. The histochemical analysis revealed that the cell lamination was prohibited by alcohol incubation. It appears that the retinal cell differentiation was inhibited. As revealed by whole mount RNA in situ hybridization, it appears that the transcription of a number of retinal-related regulatory genes, including rx1, pax6b, six3b, alpha-crystallin, rho, neuroD and huC, were all inhibited in zebrafish embryo by alcohol exposure. The transcriptional profile of alcohol-exposed embryos was also compared with normal embryos by microarray analysis at different stages. It appears that 16% of retinal-related genes were all repressed by 1.5% alcohol incubation, including several retina-related transcriptional factors, including crx, rybp, irx4a, optx2, rx1, brn3b1and vsx1. Our results suggest that alcohol did not interfere the early development of the eye, but has inhibited the final cell differentiation of retina cells. This study helps us understand the molecular mechanism of alcohol-mediated retinal malformation.
溫度與光週期對淡黃蝶的影響
為了了解淡黃蝶Catopsilia pomona無紋型crocale-like及銀紋型pomona-like中間受到環境因子的差異。先比對兩型的粒線體DNA,之後模擬夏季和冬季自然環境進行實驗。得知兩型為同種。另一方面進行溫度和光週期的實驗,顯示淡黃蝶幼蟲和成蟲雌雄個體各部位會受到此兩環境因子的影響。In order to realize if Catopsilia Pomona and Catosilia crocale are the same species, we analyzed and compared the DNA sequences of Mitochondria, and the result revealed they are indeed the same species. Then we observed the developmental process of the butterfly, and inspected the effects of different factors: photoperiod and temperature were shown to affect the phenotype of the butterfly; lower temperature and shorter day resulted in phenotypic shift from crocale-like to pomona-like, and vice versa. Also, the conflicting factors produced intermediated form. (e.g. lower temperature with longer day) Not only changed the phenotypes of adult with photoperiod and temperature, those of larvae also did. However, the mechanism how photoperiod and temperature affect the phenotype of the butterfly is unknown.