Colocalization is an important finding in many cell biological studies. This unit describes a protocol for quantitative evaluation of images with colocalization based on the calculation of a number of specialized coefficients. First, images of double-stained sections are subjected to background correction. Then, various coefficients are calculated. Meanings of the coefficients and a guide to in...

1. Introduction Fluorescence labeling techniques are quite useful to microscopists. Not only can fluorescent probes label sub-cellular structures with a high degree of specificity, they can also do so with a very high degree of sensitivity. This combination of specificity and sensitivity permits observations of cellular events that are not always visible using traditional methodologies, such as...

Quantitative colocalization analysis is an advanced digital imaging tool to examine antigens of interest in immunofluorescence images obtained using confocal microscopes. It employs specialized algorithms to estimate the degree of overlap of fluorescence signals and thus enables acquiring important new information not otherwise obtainable using qualitative approaches alone. As raw confocal imag...

Quantitative colocalization studies suffer from the lack of unified approach to interpret obtained results. We developed a tool to characterize the results of colocalization experiments in a way so that they are understandable and comparable both qualitatively and quantitatively. Employing a fuzzy system model and computer simulation, we produced a set of just five linguistic variables tied to ...

Fluorescence double-labeling is an important method for investigating associations of molecules (1). For example, evidence of co-association of proteins often includes demonstrating that they are colocalized in the same compartment of the cell. Furthermore, colocalization studies are not limited to proteins but also include measuring the colocalization of separate lipid species (8), lipids with...

The interaction, binding, and colocalization of two or more molecules in living cells are essential aspects of many biological molecular processes, and single-molecule technologies for investigating these processes in live cells, if successfully developed, would become very powerful tools. Here, we developed simultaneous, dual-color, single fluorescent molecule colocalization imaging, to quanti...

BACKGROUND Colocalization analysis of confocal fluorescence and electron microscopy (EM) are important tools to detect the expression of multiple anterior pituitary hormones within the same cell. Heterozygous (Men1+/-) mice developed pituitary tumors, mostly reported somatolactotrophinomas and ACTH secreting pituitary adenomas but also nonfunctioning tumors. The aim of the study was to run immu...

It is generally accepted that the functional compartmentalization of eukaryotic cells is reflected by the differential occurrence of proteins in their compartments. The location and physiological function of a protein are closely related; local information of a protein is thus crucial to understanding its role in biological processes. The visualization of proteins residing on intracellular stru...

The incidence of colocalization of galanin (GAL) in luteinizing hormone-releasing hormone (LHRH) neurons is 4- to 5-fold higher in female than male rats. This fact and the finding that the degree of colocalization parallels estradiol levels during the estrous cycle suggest that GAL is an estrogen-inducible product in a subset of LHRH neurons. To analyze further this paradigm we evaluated the ef...