#科洛克2是什么
Coloc 2 是斐济的共定位分析插件。它实现并执行 Pearson’s correlation, r、Manders、Costes、Li等空间方法中的像素强度相关性,用于散点图、分析、自动阈值和统计显着性测试。
Coloc 2 不执行基于对象的共定位测量,其中首先从图像中分割对象,然后测量它们的空间关系(例如重叠等)。这种补充方法在其他位置以多种方式实施。
There are many nuances and pitfalls to colocalization analysis. As such, we strongly recommend you read the Colocalization Analysis imaging tutorial before attempting to use Coloc 2!
如何使用 Coloc 2
- 阅读描述您将要执行原始论文的分析。
- Don’t treat this tool as a black box - try to understand what the strengths and limitations are and what the results could mean.
- Pearson
- Manders paper
- Costes paper
- Li paper 2.打开图像进行分析。
- You need a 2 color channel image. If the image has more than 2 channels, identify the two you want to analyze with each other, then split the channels into separate images (Image- Color - Split Channels)
- Z stacks work fine. But time series will fail until that is fixed. For now, please split the time series into a numbered set of images and analyse those one by one. See https://github.com/fiji/Colocalisation_Analysis/issues/6 3.您可以分析某些感兴趣的区域(ROI),有2种方法可以实现这一点:
- Select a region of interest with one of the ImageJ selection tools, in one of the images.
- If the image is a z stack, then the ROI applies in all “slices” of the stack.
- You can have a third “binary mask” image, with the same x,y,z dimensions as the 2 images to be analyzed:
- where the mask image is white (255 pixel value for an 8 bit greyscale image) colocalization will be analyzed for those pixels only. Where it is black (zero pixel value), the pixels will be ignored: not included in the analysis.
- you can use a z stack as a 3D mask… it’s up to you how you make that mask image, manually or by some automated method. 4.从菜单项启动Coloc 2 插件:Analyze › Colocalization Analysis › Coloc 2
- or use the search bar: press ↵ Enter then start typing
coloc, then choose the plugin with the arrow keys and press L, orDouble Click it to launch the plugin.
- Don’t treat this tool as a black box - try to understand what the strengths and limitations are and what the results could mean.
- 在插件的图形用户界面 (GUI) 中,在前 2 个下拉列表中要选择分析的 2 个图像。
- Select the images according to which you want to be channel 1 and which to be channel 2.
- In the third drop down list selection, select the image/channel you want to use that has the correct ROI or mask image
- remember: for the mask image - it must have the same xyz dimensions (number of pixels and slices) as the other 2 images.
- 选择运行哪些“算法”以及要计算哪些统计数据,以及是否要保存“标准化”PDF结果文件,单击“确定”按钮。
- Numerical results and image names are dumped into the ImageJ Log window as comma separated values, so you can copy paste, or save the log window contents, to then import them into whatever statistical package or spreadsheet in which you wish to analyze the results.
- Turn the options on/off by clicking the selection button at the left of the Algorithm description
- Also choose the approximate size of the point spread function (PSF) in your images, as well as the number of iterations to run the Costes statistical significance test (We suggest a large number… the larger the number, the longer the analysis will take. Do, at the very very least, 10 iterations (100 would be better).)
- You should know approximately how big the PSF is (in pixels) in your images.
- If you don’t, go back and read about: What is the PSF? Why is it important in colocalization analysis? (for instance: read the Costes paper )
- This size determines what size of image ‘chunks’ are shuffled in the randomization process. (PSF-sized image pieces make physical sense, as that’s the size of the smallest features visible in the image.) 7.点击“确定”运行分析。
- 结果gui将打开,显示数字表和几张图像之一
- the images can be chosen on the Dropdown list.
- You can see the 2 Li plots, a scatterplot or 2D histogram with regression line, and input images and Roi.
- the scatter plot uses fire colour look up table.
- the log checkbox allows display of images with or without log scaling, useful for eg. the scatterplot
- 系统会询问结果是否保存为您的PDF文件(如果选中了“显示保存PDF对话框”按钮)。因此请告诉它保存PDF的位置。这是标准输出格式,因此您可以与您的朋友进行比较,相同与相同。
- Feel free to tell us what things you think should be included in this standardized PDF output file and how it should be formatted. HTML? XML? Plain text?
Manders 和 Costes 方法的陷阱
- Feel free to tell us what things you think should be included in this standardized PDF output file and how it should be formatted. HTML? XML? Plain text?
如果输入不合适的信息,自动阈值计算方法可能会失败
这意味着它不喜欢高零偏移的图像,在这些图像中没有检测到光仍然会给出很大的非零像素值。例如,数码相机的零偏移/偏移具有或共焦PMT另外,高而不稳定的非特定背景信号导致同样的问题。这些都为每个像素的强度值添加了一个不同,适配并模糊了与每个像素检测到的染料关系染料“浓度”的真实比例。如果不包含真实的(特定)信号的像素具有更大的强度值,则该算法在不知道所有像素中的非零强度偏移的情况下,会假设该偏移是要处理的真实信号,并且可以达到其中一个或两个阈值低于图像的该颜色通道中的最低强度值的阈值的结果。这意味着通道的所有像素都被认为是共定位的,那么您获得的曼斯系数将反映这种异常的、不切实际的情况。在这些情况下,在运行中Coloc 2 或 Colocalization Threshold 插件之前,应仔细删除/背景丢失和/或偏移。下图是这种情况的例子,使用行为不良的数据集:150707_WTstack.lsm。请注意,M1 和 tM1 的值相同!情况不应该如此。您可以看到绿色通道阈值被错误地设置为低于图像数据强度实际开始的强度。
注意:图像包含大面积的背景,两个通道中的像素强度值相似。这意味着背景区域存在极大的相关性,从而干扰了生物所在的高信号区域中的生物相关性。这意味着设置生物学相关的感兴趣区域(ROI)而分析整个图像非常重要。必须分析我们的高度避免相关但无趣的背景区域。请参阅下面的部分…

噪声对 Pearson 和 Manders 系数的影响
在完美共定位的情况下,2个通道的强度始终完全相关:低红色与低绿色,高绿色与高红色,散点图代表所有数据点都为直线对角线,因为绿色强度始终与红色强度成比例!然而,这是理想情况,真实的生物数据是有噪音的!噪声(无论是来自未染色每个分子的染料,还是来自记录太少光子信号统计的光子粒散噪声,或来自其他电子噪声源)都会导致噪音强因此,您可以通过查看散点图点与线性回归线的分布程度或严格程度来了解噪声。另外,由于曼德斯系数测量的相关性,而噪声会降低两个相同信号的相似性,因此噪声分布曼德斯系数降低到低于噪声极低的图像应有的系数。 Pearson相关性也是如此。因此,对于显微镜下的同一目标,噪声增大的图像似乎比干净、低噪声的图像提供的共定位要少。这意味着您无法比较不同信号:噪声水平的不同图像,除非您有某种方法来估计噪声并由此进行校正。
应损耗背景和数字偏移(这不会影响皮尔逊测量,但会影响其他测量),并且应滤除、抑制或通过收集附近的光子来最好地避免噪声。反之补充是恢复图像的好方法,通过加权噪声和消除偏移或背景来更好地估计真实的波形团空间分布,同时通过将空间频率响应到物镜分辨率来提高分辨率和动态范围。共焦也应该去终点,不仅仅是宽场图像,尤其是在低信号和高噪声的情况下。
荧光发射渗透看起来非常完美的共定位
对于 DAPI 核染色和 GFP 染料来说,通常是这样,当同时捕获图像剂时,同时激发和检测两种染料,荧光发射渗透会产生误差结果,来自 DAPI 因为信号也出现在 GFP 检测通道中! DAPI 越多,GFP通道中的信号也很好定位。这看起来确实是共定位的,但当然这是完全错误的!这是成像系统设置不正确或使用不正确的问题。如果许多其他染料组合重叠的发射光谱,也会发生这种情况。经常检查您的光谱。您可以在这里执行此操作:Invitrogen Fluorescent Dye Spectra Viewer。为了安全起见,请检查您的滤光片组是否输入错误的信号,并执行“顺序测量”,这样您一次就只能启动一种染料并进行结论。

感兴趣区域 (ROI)
是否将零 -零像素视为算法要处理有趣数据的一部分。如果您考虑一下,在荧光图像中通常有相当大的区域在两个通道中都是黑色的。例如,细胞之间有空间,或者两个通道中都没有信号,因为该区域不属于样品的感兴趣区域。这是一个重要的哲学观点:为什么要费心拍摄黑色区域的为什么要费力分析黑色区域的共定位?您肯定对这些区域不感兴趣,因为它们不包含对您有用的信息?如果您执行这些像素强度相关方法并包含零零像素,那么这些像素当然具有非常高的相关性!它们具有相同的价值。但它们完全无趣!当然,自动阈值方法将它们排除在tM1 和 tM2数据排除,但为什么首先要包含它们呢?除非有充分的理由,否则最好不要包含它们。为什么不直接对区域进行结论,或者只是分析发生生物学现象的区域?如果您分析大面积接近零和零强度的图像,自动则阈值方法将倾向于降低阈值以包含更如果您对相同的样本进行成像,但仅对感兴趣的部分(例如细胞质)的单个块进行成像,那么自动阈值可能会给出更高的阈值,并排除更多不感兴趣的背景,因此阈值化的曼德斯函数将更好地反映图像数据的生物学感兴趣的部分- 吧?您可以通过制作 ROI 然后选择插件中的使用 ROI 选项来仅分析感兴趣的区域。您可以使用常规形状(形状或形状)甚至牵涉 ROI 来手动选择图像中的有趣部分,并忽略您知道的背景部分。是的,这是一个结果,所以要小心!您可以在下面的示例屏幕截图中看到,对于相同的不当行为的数据集对,使用粗略地获取单元格的 ROI,正确计算阈值,以及 tM1 和tM2是合理的并且低于1.00:

其他陷阱
请参阅Colocalization Analysis页面进一步讨论预防措施。
发行说明、新增功能和已修复的错误
新功能和修复的最终列表是源代码历史记录,所以处的 GIT 历史记录如下所示:https://github.com/fiji/Colocalisation_Analysis/commits/master>这只是一种简单的检查方法,是用户的临时列表,并且可能不是最新的。这些可能还没有全部包含在发布到 imageJ/Fiji 更新程序中的 Coloc_2 插件版本中;您可以看到搜索栏详细信息继续中推出的该版本。最新发布到斐济的更新程序版本被标记为 GITHUB 上的版本,例如。 <https://github.com/fiji/Colocalisation_Analysis/releases>
1.斐济更新程序中的版本2.0.2 - 2015年2月26日 1. 27-Jan-2015 commit 863fdbeaf7785759ed1c8e9357b7dd67f6d79996 Implement implement code to make sure autothreshold results are the same regardless of image channel order. A slightly earlier commit also added a unit test for this: CommutativityTest.java
- Fiji 更新程序中的版本 2.1.0 - 2015 年 9 月 2 日
- 08-2015 Fix bug in Manders’ split coefficient calculations when using thresholds. https://github.com/fiji/Colocalisation_Analysis/commit/e4a3a6ec36e0e878d40e1b1114f68deaccd41cde
- 08-2015 Fixed in fiji master github repo by commit https://github.com/fiji/Colocalisation_Analysis/commit/492b846c032bd85651ffce7b52c96b3520eff6bb:
- if 2D histogram regression finds a y intercept that is below zero it gives the too high warning “Warning! y-intercept high - The absolute y-intercept of the auto threshold regression line is high. Maybe you should use a ROI, maybe do a background subtraction in both channels” So should change warning text to too high or too low depending on if its positive or negative.
- 08-2015 Fixed in fiji master github repo by commit https://github.com/fiji/Colocalisation_Analysis/commit/4cfc8861f05f277075c3fb7881ebf0d7e54c67c3:
- Numerical results and image stats are currently spewed into the IJ.log window. This is done separately from the way results are put into the simple results display window or the PDF output. So there three differently formatted results outputs with different stuff in them. Different ResultsHandler implementations like PDF or Simple can and do show a different selection of results. This is over complicated, so it should be made into one thing, that outputs the same numerical results and stats values, in the same order in all ResultsHander implementations: GUI display and PDF output, and also the IJ.log. Can reuse the ValueResults class for all three by doing the same thing in each.
- commit https://github.com/fiji/Colocalisation_Analysis/commit/a493b2c88a14f4f6403451aeee6989bf7a2becfb Make IJ.log writing only happen once and only in the default ResultHandler that’s always used.
- commits https://github.com/fiji/Colocalisation_Analysis/commit/e833597d7d8a7b4d3db747512f6048d67d61d120>和<https://github.com/fiji/Colocalisation_Analysis/commit/75184e88cd6c1e0914ec87caebe97494002bcd4e Get the Coloc job name from the DataContainer image names, and also add the mark/ROI ID to the job name in case there are multiple ROIs.
- Numerical results and image stats are currently spewed into the IJ.log window. This is done separately from the way results are put into the simple results display window or the PDF output. So there three differently formatted results outputs with different stuff in them. Different ResultsHandler implementations like PDF or Simple can and do show a different selection of results. This is over complicated, so it should be made into one thing, that outputs the same numerical results and stats values, in the same order in all ResultsHander implementations: GUI display and PDF output, and also the IJ.log. Can reuse the ValueResults class for all three by doing the same thing in each.
- 08-2015 Fixed in fiji master github repo commit https://github.com/fiji/Colocalisation_Analysis/commit/6318f0f29ba6fd938674225a43cdba4c0909acc6:
- Running as imageJ macro command fails because of the parameter: show_“save_pdf”_dialog. Probably the “” are messing up the run(Coloc_2, “params”); text string parameters. So need to get rid of the “” around save_pdf.
1.2.1.0版本之后 1. 09-2015 Fixed in fiji master github repo commit: Coloc Job filed and result nanme in output fixed to be more sensible formatting, with a label and a value like all other results
想法列表
Coloc_2 问题跟踪器以及源代码可在 GITHUB.com 上找到;可以在那里报告错误:
可以在这里查看未解决的错误报告和其他未解决的问题:
已修复的错误和已解决的问题可以在上面的部分中查看,并在问题跟踪器中查看更多详细信息:
旧的“待办事项”列表和设计说明的内容可以在这里找到:
此列表适用于更多随机、模糊或不确定的想法,这些想法尚未经过充分考虑,无法在 GITHUB.com 的跟踪器中充分定义可解决的问题。
1.作为宏命令循环运行,需要使用宏命令保存IJ.log窗口结果,然后在下一组结果发送到那里之前清除日志窗口。在文档中添加文字来解释这一点。应该使用字符串连接来测试这件事是否有效,以构建Coloc_2参数的长字符串。也许用Python或BeanShell会更好。
这个宏将提示您输入一个目录,并获取该目录中所有文件的列表,这些文件存储在名为“files”的数据库中(或您选择的任何名称):
然后,您可以使用阵列索引中的连续数字来引用连续文件,例如:
files[0]和files[1].用于遍历整个列表:dir = getDirectory(); files = getFileList(dir); for(i = 0; i < files.length - 1; i++){ open(dir + files[i]); open(dir + files[i+1]); Split channels run(Coloc_2, "i-ch1, i-ch2, etc....") Close opened images Save ij.log Clear ij.log }