近日,，英國(guó)醫(yī)學(xué)研究理事會(huì)的科學(xué)家使用一種光學(xué)投影層析成像技術(shù),，首次獲得果蠅內(nèi)部結(jié)構(gòu)的3D圖像,，這有利于加速對(duì)老年癡呆癥和影響人類腦細(xì)胞的其他疾病的基因?qū)W研究。
在9月份的《公共科學(xué)圖書(shū)館·綜合》（PLoS ONE）雜志上,，該研究小組描述了他們?nèi)绾卫霉鈱W(xué)投影層析成像技術(shù)獲得成熟果蠅腦內(nèi)部圖像,，并對(duì)其大腦退化情況進(jìn)行研究。醫(yī)學(xué)研究理事會(huì)的博士生李安內(nèi)·穆葛解釋說(shuō)：“果蠅外骨骼顏色較暗,，所以無(wú)法使用標(biāo)準(zhǔn)光學(xué)顯微鏡從里面觀察,。這意味著過(guò)去研究者必須解剖其組織獲得信息?，F(xiàn)在我們通過(guò)漂白其骨骼解決了這個(gè)問(wèn)題，當(dāng)果蠅變成無(wú)色時(shí),，利用成像技術(shù)不僅可以觀察內(nèi)部器官還可以生成整個(gè)果蠅的二維和三維圖片,。”
領(lǐng)導(dǎo)該研究的醫(yī)學(xué)研究理事會(huì)人類基因?qū)W研究部的瑪麗說(shuō)：“在阿爾茨海默病、帕金森和運(yùn)動(dòng)神經(jīng)原疾病中會(huì)發(fā)生神經(jīng)退行性病變,，也就是腦細(xì)胞功能會(huì)慢慢退化,，但這種病變并不僅僅存在于人類也發(fā)生在昆蟲(chóng)中。如秋季蜜蜂和黃蜂在死亡前通常會(huì)有很多怪異行為,。”
果蠅和人類有很多基因的功能類似,，因此常被用來(lái)研究基因如何影響人類疾病，但由于其頭部和大腦非常脆弱而給研究帶來(lái)障礙,。光學(xué)投影層析能幫助研究者不用解剖就能觀察果蠅大腦如何隨特定基因活動(dòng)而變化,，還能了解不同基因的表達(dá)形式，從而有助于確認(rèn)控制中樞神經(jīng)系統(tǒng)的基因,，為人類大腦研究提供重要參考信息,。（科技日?qǐng)?bào)）
原始出處:
PLoS ONE
Received: June 15, 2007; Accepted: August 8, 2007; Published: September 5, 2007
Three-Dimensional Imaging of Drosophila melanogaster
Leeanne McGurk1, Harris Morrison1, Liam P. Keegan1, James Sharpe2, Mary A. O'Connell1*
1 Medical Research Council Human Genetics Unit, Edinburgh, United Kingdom, 2 Systems Biology Program, Centre de Regulació Genòmica, Barcelona, Spain
Background
The major hindrance to imaging the intact adult Drosophila is that the dark exoskeleton makes it impossible to image through the cuticle. We have overcome this obstacle and describe a method whereby the internal organs of adult Drosophila can be imaged in 3D by bleaching and clearing the adult and then imaging using a technique called optical projection tomography (OPT). The data is displayed as 2D optical sections and also in 3D to provide detail on the shape and structure of the adult anatomy.
Methodology
We have used OPT to visualize in 2D and 3D the detailed internal anatomy of the intact adult Drosophila. In addition this clearing method used for OPT was tested for imaging with confocal microscopy. Using OPT we have visualized the size and shape of neurodegenerative vacuoles from within the head capsule of flies that suffer from age-related neurodegeneration due to a lack of ADAR mediated RNA-editing. In addition we have visualized tau-lacZ expression in 2D and 3D. This shows that the wholemount adult can be stained without any manipulation and that this stain penetrates well as we have mapped the localization pattern with respect to the internal anatomy.
Conclusion
We show for the first time that the intact adult Drosophila2 can be imaged in 3D using OPT, also we show that this method of clearing is also suitable for confocal microscopy to image the brain from within the intact head. The major advantage of this is that organs can be represented in 3D in their natural surroundings. Furthermore optical sections are generated in each of the three planes and are not prone to the technical limitations that are associated with manual sectioning. OPT can be used to dissect mutant phenotypes and to globally map gene expression in both 2D and 3D.
Figure 2. The data output.
The data from the scans are reconstructed in 3D, the two datasets, brightfield (red, exoskeleton) and fluorescent (green, anatomy), are superimposed, and the information is displayed in all three planes (A–D). Single heads can be imaged (E). The data can also be displayed and explored in 3D (F, G).
