Two-dimensional electrophoresis image interpretation

Open Platform Cameras Based Bio-Imaging Evaluation System

With the active development of mobile devices, a variety of ultra-small, high-definition, and open platform-based cameras are being mass-produced. In this paper, we established an emulation system to verify the bio-imaging performance of the bulky and expensive high-performance cameras and various smartphone cameras that have been used in bio-imaging devices. In the proposed system, the linearity of the brightness gradient change of four types of cameras was compared and analyzed. Based on these results, three cameras were selected in order of excellent linearity, and gel image analysis results were compared.

Dataset of Two-Dimensional Gel Electrophoresis Images of Acute Myeloid Leukemia Patients before and after Induction Therapy

Acute myeloid leukemia (AML) is a malignant disorder of the hematopoietic stem and progenitor cells, which results in the build-up of immature blasts in the bone marrow and eventually in the peripheral blood of affected patients. Accurately assessing a patient´s prognosis is very important for clinical management of the disease, which is why there are several prognostic factors such as age, performance status at diagnosis, platelet count, serum creatinine and albumin that are taken into account by the clinician when deciding the course of treatment. However, proteomic changes related to treatment response in this patient group have not been widely explored. Here, we make available a set of 22 two-dimensional gel electrophoresis (2DGE) images obtained from the peripheral blood samples of 11 patients with AML, taken at the time of diagnosis and after induction therapy (approximately 21–28 days after starting treatment). The same set of 2DGE images is also made available after a preprocessing stage (an additional 22 2DGE pre-processed images), which was performed using algorithms developed in Python, in order to improve the visualization of characteristic spots and facilitate proteomic analysis of this type of images.

An alternative method for electrophoretic gel image analysis in the GelMaster software

A novel methodology of electrophoretic gel image analysis has been proposed that is based on two-dimensional image processing methods instead of previously used one-dimensional Gaussian deconvolution. The crucial problem of the analysis of imperfect gels, that consists in band detection, is solved using the algorithms of band boundary detection and intensity homogeneity indication. The template approach represents the core element of the developed algorithms. The GelMaster software system has been developed in which the novel algorithms are implemented. It involves two-stage interaction with the user: detection of the true bands and deleting the false band detections. The main features of the GelMaster system and the most important algorithms are described.

Effect of NO donors on protein phosphorylation in intact vascular and nonvascular smooth muscles

It is generally well accepted that nitrovasodilator-induced relaxation of vascular smooth muscle involves elevation of cGMP and activation of a specific cGMP-dependent protein kinase [protein kinase G (PKG)]. However, the protein targets of PKG and the underlying mechanisms by which this kinase leads to a relaxant response have not been elucidated. Several types of smooth muscle, including rat myometrium and vas deferens, are not relaxed by sodium nitroprusside, even at concentrations that produce marked elevation of cGMP and activation of PKG. The main objective of our studies was to compare PKG-mediated protein phosphorylation in intact rat aorta, rat myometrium, and rat vas deferens using two-dimensional gel electrophoresis. In intact rat aorta, seven PKG substrates were detected during relaxation of the tissue. None of the PKG substrates identified in the rat aorta appeared to be phosphorylated in the myometrium or vas deferens after administration of various cGMP-elevating agents. Thus the failure of the rat myometrium and rat vas deferens to relax in the face of cGMP elevation and PKG activation may be due to a lack of PKG substrate phosphorylation.

An updated two-dimensional gel electrophoresis technique for the detection of drug-induced changes in protein phosphorylation in intact smooth muscle

Two-dimensional gel electrophoresis is widely used in many areas of scientific research. The necessity for greater resolution and more sensitive protein detection with this technique have resulted in a steadily changing methodology. Complete descriptions of some aspects of two-dimensional gel electrophoresis are available in the earlier literature. However, simplified methods incorporating recent advances specifically designed to use two-dimensional gel electrophoresis for the measurement of protein phosphorylation in intact tissue are lacking. This report describes, in detail, each of the steps involved in carrying out such measurements including intact tissue labeling with 32P, homogenization and protein sample preparation, two-dimensional gel electrophoresis using isoelectric focusing followed by vertical second-dimension SDS-PAGE, staining, autoradiography, and quantitative analysis of changes in phosphorylation of specific proteins. This method incorporates a number of modifications taken from other published sources and includes several novel changes developed in our laboratory. To illustrate the utility of this technique we have included a set of results analyzing the phosphorylation patterns induced by the addition of a nitric oxide donor, sodium nitroprusside, to intact strips of rat aorta. We were able to demonstrate SNP-induced phosphorylation of a number of proteins, several of which have not been previously described in earlier reports in which the patterns of PKG-mediated phosphorylation were investigated.