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PubMed1976

Differential gene expression in multilocus isozyme systmes of the developing green sunfish.

The patterns of expression of eight multilocous isozyme systems were investigated in the differentiated adult tissues and the early embryonic stages (0-210 hours after fertilization) of the green sunfish, Lepomis cyanellus. Enzymes encoded by approximately 23 gene loci were resolved by starch-gel electrophoresis and detected by specific histochemical staining. The developmental patterns of these isozyme systems appear to be the result of the diffential expression of the multiple gene loci. Isozymic forms of glucoseophosphate isomerase (GPI-A2), malate dehydrogenase (MDH-A2), and creatine kinase (CK-C2) were present in most differentiated tissues, in the unfertilized eggs, and in all stages of embryonic development. Closely homologous forms of these isozymes (GPI-B2, MDH-B2, and CK-A2) were expressed predominantly in skeletal muscle and were first detected at around the time of hatching (38-42 hours). The similar temporal and spatial patterns of gene expressions for the GPI, LDH, MDH, and CK loci suggest that the duplicates loci encoding enzymes, diverged in their regulation to patterns of differential gene expression which are similar for each enzyme system.

Adenylate Kinase↗
PubMed2005

Spatial and temporal expression patterns of the choroideremia gene in the mouse retina.

PURPOSE: Choroideremia (CHM), an X-linked retinal disease, is caused by mutations affecting the CHM gene. This gene encodes REP-1, which functions in the covalent modifications of proteins involved in vesicle trafficking. The disease affects several cell types in the retina, but it is not known which cell types contribute directly or indirectly to disease progression. A study of the expression patterns of Chm and the related gene Chml in the mouse retina was undertaken in order to address this issue. METHODS: The expression patterns of Chm and Chml were determined by in situ hybridization. The localization of the Chm protein product, Rep-1, was determined spatially and temporally in the mouse retina by immunohistochemistry. RESULTS: Chm and Chml mRNA were found in every major layer of the retina in adult mice. During development, Rep-1 protein localization changes from a fairly diffuse pattern during embryogenesis to a more specific pattern at the time of retinal differentiation. In adulthood, Rep-1 localizes to distinct cellular compartments in multiple retinal cell types. CONCLUSIONS: Chm and Chml have the same broad expression profile in the mouse retina. In particular, the Chm transcript and corresponding protein are found in cell types other than those thought to be primarily affected in the human disease. These results have important implications for approaches with which to develop a relevant mouse model of choroideremia and for therapeutic strategies for this disease.

Adaptor Proteins, Signal Transducing↗
PubMed1993

Spatially restricted expression of Dlx-1, Dlx-2 (Tes-1), Gbx-2, and Wnt-3 in the embryonic day 12.5 mouse forebrain defines potential transverse and longitudinal segmental boundaries.

The expression patterns of four genes that are potential regulators of development were examined in the CNS of the embryonic day 12.5 mouse embryo. Three of the genes, Dlx-1, Dlx-2 (Tes-1), and Gbx-2, encode homeodomain-containing proteins, and one gene, Wnt-3, encodes a putative secreted differentiation factor. These genes are expressed in spatially restricted transverse and longitudinal domains in the embryonic neural tube, and are also differentially expressed within the wall of the neural tube. Dlx-1 and Dlx-2 are expressed in two separate regions of the forebrain in an identical pattern. The Gbx-2 gene is expressed in four domains, two of which share sharp boundaries with the domains of the Dlx genes. One boundary is in the basal telecephalon between deep and superficial strata of the medial ganglionic eminence; the other boundary is in the diencephalon at the zona limitans intrathalamica. The Wnt-3 gene is expressed in a dorsal longitudinal zone extending from the hindbrain into the diencephalon, where its expression terminates at the zona limitans intrathalamica. Reciprocal patterns of expression are found within the dorsal thalamus for the Gbx-2 and Wnt-3 genes. These findings are consistent with neuromeric theories of forebrain development, and based upon them we suggest a model for forebrain segmentation.

Animals↗
PubMed1996

Expression of type XII collagen by wound epithelial, mesenchymal, and ependymal cells during blastema formation in regenerating newt (Notophthalmus viridescens) tails.

Previously we showed that type XII collagen (col XII) is highly upregulated in the regenerating newt (Notophthalmus viridescens) forelimb. Here, using immunohistochemistry and in situ hybridization, we studied the pattern of expression of col XII during early stages of adult newt tail regeneration. The results show that immunoreactivity of col XII is first seen as a thin layer beneath the wound epithelium (WE) at 3 days after amputation. Reactivity associated with the mesenchyme becomes obvious at day 4 and increases considerably between days 6 and 7 after amputation. In situ hybridization indicates that the early WE-associated reactivity and later mesenchymal reactivity are due to increased col XII gene expression by the WE and mesenchyme, respectively. At 7 days after tail amputation both wound epithelial and mesenchymal cells exhibit a strong riboprobe signal. Interestingly, a distinct riboprobe signal is also seen in the cells of the outgrowing ependymal tube at day 7 but little if any col XII immunoreactivity is present. The spatial pattern of col XII gene expression changes by day 14 after amputation in that transcription in mesenchyme is maintained at a high level, in the WE it is reduced, and in ependyma it ceases to be detectable. Local deprivation of the spinal cord significantly lowers the level of col XII message in the mesenchyme. Much of this decrease in transcription is due to minimal mesenchymal cell accumulation secondary to spinal cord ablation. The temporal and spatial patterns of expression of the col XII gene in the WE, mesenchyme, and ependyma during tail regeneration strongly suggest a role for col XII in regulating both spinal cord outgrowth and spinal cord-dependent tail regeneration.

Amputation, Surgical↗
PubMed1996

Expression of alpha 2-adrenergic receptor subtypes in the mouse brain: evaluation of spatial and temporal information imparted by 3 kb of 5' regulatory sequence for the alpha 2A AR-receptor gene in transgenic animals.

The present studies characterize the expression of the alpha 2A, alpha 2B and alpha 2C adrenergic receptor subtypes via in situ hybridization analysis of messenger RNA expression in the adult mouse brain, as well as the pattern of expression of alpha 2A adrenergic receptor messenger RNA at embryonic day E9.5, the earliest time for detection of the messenger RNA encoding this receptor subtype. alpha 2A adrenergic receptor messenger RNA is highly expressed in the sixth layer of the cortex and the locus coeruleus, alpha 2B adrenergic receptor messenger RNA predominantly in the thalamus and in the Purkinje layer of the cerebellum, and alpha 2C adrenergic receptor messenger RNA in the putamen caudate region of the mouse brain. Both alpha 2A and alpha 2C adrenergic receptor messenger RNA demonstrate strong expression in the amygdaloid complex, hypothalamus, olfactory system and the hippocampal formation. To develop a molecular understanding of the unique cellular expression of messenger RNA encoding the alpha 2A adrenergic receptor subtype, 2.83 kb of the upstream regulatory sequence for the alpha 2A adrenergic receptor gene was fused to the LacZ gene as a reporter gene and expression of beta-galactosidase activity was assessed in transgenic offspring. Although the spatial expression of the transgene in the adult brain often overlaps that for the endogenous alpha 2A adrenergic receptor, both ectopic expression and the absence of appropriate expression were noted; in contrast five of the six lines show temporal expression characteristic of the endogenous alpha 2A adrenergic receptor gene. The present studies provide the first characterization of messenger RNA localization for the three alpha 2 adrenergic receptor subtypes in the mouse CNS. Because the functional roles of the prazosin-sensitive alpha 2B adrenergic receptor and alpha 2C adrenergic receptor subtypes have been masked in most earlier physiological and pharmacological analyses of alpha 2 adrenergic receptor function, identifying the multiple loci alpha 2 adrenergic receptor subtype expression is an important prelude to understanding the functional roles of these three independent receptor populations in the mouse CNS. The findings in the transgenic animals indicating that approximately 3 kb of regulatory sequence has imparted faithful temporal but not spatial expression for the alpha 2A adrenergic receptor gene suggest that additional regulatory information is necessary for appropriate cell specific expression of messenger RNA for the alpha 2A adrenergic receptor subtype.

Amino Acid Sequence↗
PubMed1991

cAMP and cell sorting control the spatial expression of a developmentally essential cell-type-specific ras gene in Dictyostelium.

The Dictyostelium ras gene (Dd-ras) is expressed at a low level in vegetative cells, is not expressed between the onset of development and aggregation, and is then re-expressed in the multicellular aggregate stages from the distal, now cAMP-responsive, promoter and from two more proximal promoters. Expression of activated Dd-ras (G12----T12) (Reymond et al. 1986) results in an abnormal developmental phenotype with the formation of aggregates having multiple tips and an inhibition of further development. In this report we investigate the spatial expression of Dd-ras by fusing the 5'-flanking region to the Escherichia coli lacZ gene and by staining aggregates for beta-galactosidase (beta-gal) activity. We show that fusions using 5'-flanking sequences that include all promoters are expressed in approximately 10-20% of the cells randomly scattered within the early aggregate. Our data indicate that these beta-gal-expressing cells migrate to newly formed tips of aggregates and localize in the region that becomes the prestalk zone. Staining is also seen in the very posterior of the organism. The anterior staining appears to be specific for the prestalk A population, and beta-gal activity is subsequently present in stalk cells as developmental proceeds. When only the two more proximal promoters are used to drive lacZ expression, localized staining is seen in the anterior prestalk region, although it is weaker than with the construct carrying all promoters. Moreover, staining is not seen in the posterior domain in the first finger stage, suggesting differences in the spatial expression from the different promoters. Staining is also observed in some cells within the prespore region, which could be anterior-like cells. The pattern of Dd-ras/lacZ staining during tip formation suggests a directed, spiral pattern of cell migration, possibly in response to the proposed spiral gradient of cAMP within the developing aggregate. The pattern of Dd-ras is consistent with the abnormal developmental phenotype caused by expressing an activated Dd-ras Thr12 gene and suggests an essential role for Dd-ras in controlling spatial differentiation.

Amino Acid Sequence↗
PubMed2002

DNA microarrays and toxicogenomics: applications for ecotoxicology?

Toxicogenomics attempts to define how the regulation and expression of genes mediate the toxicological effects associated with exposure to a chemical. DNA microarrays are rapidly becoming one of the tools of choice for large-scale toxicogenomic studies. An approach in modern toxicogenomics has been to classify toxicity based on gene transcriptional patterns; comparing the transcriptional responses of a chemical with unknown toxicity to those for which the transcriptional profiles and toxicological endpoints have been well characterized. Recent evidence suggests that gene expression microarrays may be instrumental in defining mechanisms of action of toxicants. However, several assumptions are inherent to a toxicogenomic-based approach in toxicology, many of which remain to be validated. Gene expression profiling using DNA microarrays represents a snapshot of the gene transcriptional responses occurring at a particular time and within a particular tissue. Toxicity, on the other hand, represents a continuum of possible effects governed by both temporal and spatial factors that are inextricably contingent upon the exposure conditions. The perceived toxicological properties of any chemical are dependent on the route, dose, and duration of the exposure, and as such, gene expression patterns are also subject to these variables. Correct interpretation of DNA microarray data for the assessment of the toxicological properties of chemicals will require that temporal and spatial gene expression profiles be accounted for. These considerations are further compounded in ecotoxicological studies, during which altered gene expression patterns induced from exposure to an anthropogenic substance must be discernible over and above the complex effects that phenotypic, genotypic, and environmental variables have on gene expression. To this end, the greatest utility of DNA microarrays in the field of ecotoxicology may be in predicting the toxicological modes of action of anthropogenic substances on host physiology, particularly in non-model organisms. Predictable and accurate assessment of the impacts of a chemical substance in ecotoxicology will require that classical toxicological endpoints be used to validate any effects predicted based on gene expression profiling. Validated expression profiling may subsequently find utility in ecotoxicological-based computer simulation models, such as the Biotic Ligand Model (BLM), in which gene expression information may be integrated with geochemical, pharmacokinetic, and physiological data to accurately assess and predict toxicity of metals to aquatic organisms.

Journal Article↗
PubMed1997

Fibroblast growth factor 10 (FGF10) and branching morphogenesis in the embryonic mouse lung.

During mouse lung morphogenesis, the distal mesenchyme regulates the growth and branching of adjacent endoderm. We report here that fibroblast growth factor 10 (Fgf10) is expressed dynamically in the mesenchyme adjacent to the distal buds from the earliest stages of lung development. The temporal and spatial pattern of gene expression suggests that Fgf10 plays a role in directional outgrowth and possibly induction of epithelial buds, and that positive and negative regulators of Fgf10 are produced by the endoderm. In transgenic lungs overexpressing Shh in the endoderm, Fgf10 transcription is reduced, suggesting that high levels of SHH downregulate Fgf10. Addition of FGF10 to embryonic day 11.5 lung tissue (endoderm plus mesenchyme) in Matrigel or collagen gel culture elicits a cyst-like expansion of the endoderm after 24 hours. In Matrigel, but not collagen, this is followed by extensive budding after 48-60 hours. This response involves an increase in the rate of endodermal cell proliferation. The activity of FGF1, FGF7 and FGF10 was also tested directly on isolated endoderm in Matrigel culture. Under these conditions, FGF1 elicits immediate endodermal budding, while FGF7 and FGF10 initially induce expansion of the endoderm. However, within 24 hours, samples treated with FGF10 give rise to multiple buds, while FGF7-treated endoderm never progresses to bud formation, at all concentrations of factor tested. Although exogenous FGF1, FGF7 and FGF10 have overlapping activities in vitro, their in vivo expression patterns are quite distinct in relation to early branching events. We conclude that, during early lung development, localized sources of FGF10 in the mesoderm regulate endoderm proliferation and bud outgrowth.

Animals↗
PubMed2004

Lmx1b expression during joint and tendon formation: localization and evaluation of potential downstream targets.

The tetrapod limb exhibits distinct dorsoventral joint, tendon, and muscle asymmetry. The LIM-homeodomain transcription factor, Lmx1b, is required to achieve the dorsal character of these structures, but the mechanism by which Lmx1b orchestrates this asymmetrical development is unknown. To identify target tissues and genes regulated by Lmx1b, we examined Lmx1b expression during joint, tendon and muscle formation (9.5-16.5 dpc) and the expression of several genes spatially restricted to developing joints and associated tissues in normal and Lmx1b knockout (KO) mice including: Gdf-5, sFrp2, sFrp3, Six1 and Six2. Lmx1b was diffusely expressed in the undifferentiated dorsal mesoderm of the emerging limb bud (E9.5-E11.5). With progressive proximal to distal differentiation, Lmx1b expression localized to dorsal joint-forming regions, to developing tendons and ligaments, but not to migrating myocytes (E13.5-15.5). By E16.5, mature tendon and ligament associations were evident and Lmx1b expression had regressed. The expression patterns of Gdf-5 and sFrp3 at E15.5 were symmetrical along the dorsoventral axis in normal and Lmx1b KO mice. sFrp2, Six1 and Six2 exhibited asymmetrical dorsoventral expression and in Lmx1b KO mice, this asymmetry is lost; however, none were solely restricted to or excluded from dorsal Lmx1b expressing tissues.

Animals↗
PubMed2005

Targeting gene expression in the mouse somite: adenovirus-mediated gene delivery and whole embryo culture.

We report here a novel approach to direct gene expression in the mouse somite based on the combined application of adenovirus-mediated gene delivery and whole embryo ex vivo culture. As proof of principle, we show functional analysis of somites microinjected with an engineered virus expressing an activated form of Smoothened, the signaling receptor for Sonic Hedgehog (SHH). As adenovirus can infect many embryonic tissues in the mouse, this method may provide an effective alternative to conventional transgenesis for targeted spatial and temporal gene expression.

Adenoviridae↗
PubMed2002

A method for two-dimensional registration and construction of the two-dimensional atlas of gene expression patterns in situ.

We apply the fast redundant dyadic wavelet transform to the spatial registration of two-dimensional gene expression patterns of 736 Drosophila melanogaster embryos. This method is superior to the Fourier transform or windowed Fourier transform because of its ability to reduce noise and is of high resolution. In registration of the dataset we use two cost functions based on computing the Euclidean or Mahalanobis distance. The algorithm shows a high level of accuracy. For early temporal classes the cost function based on Mahalanobis distance gives better results. We have reported a method for construction of an integrated dataset elsewhere. In this paper the method is extended to the two-dimensional case. The procedure for data assembly provides for the preservation of some aspects of the nuclear structure of a two-dimensional gene expression pattern. It is based on creating an averaged model that reproduces the spatial distribution of nuclei over the embryo image. The average concentrations of each protein in each averaged nucleus are computed from the series of embryos of the same age.

Algorithms↗
PubMed2001

Distinctive expression of extracellular matrix molecules at mRNA and protein levels during formation of cellular and acellular cementum in the rat.

Little is known about differential expression of extracellular matrices secreted by cementoblasts between cellular and acellular cementum. We hypothesize that cementoblasts lining acellular cementum express extracellular matrix genes differently from those lining cellular cementum, thereby forming two distinct types of extracellular matrices. To test this hypothesis, we investigated spatial and temporal gene expression of selected extracellular matrix molecules, that is type I collagen, bone sialoprotein, osteocalcin and osteopontin, during formation of both cellular and acellular cementum using in situ hybridization. In addition, their extracellularly deposited and accumulated proteins were examined immunohistochemically. The mRNA transcripts of pro-alpha1 (I) collagen were primarily localized in cementoblasts of cellular cementum and cementocytes, while those of bone sialoprotein were predominantly seen in cementoblasts lining acellular cementum. In contrast, osteocalcin was expressed by both types of cementoblasts and cementocytes and so was osteopontin but only transiently. Our immunohistochemical examination revealed that translated proteins were localized extracellularly where the genes had been expressed intracellularly. The present study demonstrated the distinctive expression of genes and proteins of the extracellular matrix molecules between cellular and acellular cementum.

Animals↗
PubMed1996

The role of gap junction membrane channels in development.

In most developmental systems, gap junction-mediated cell-cell communication (GJC) can be detected from very early stages of embryogenesis. This usually results in the entire embryo becoming linked as a syncytium. However, as development progresses, GJC becomes restricted at discrete boundaries, leading to the subdivision of the embryo into communication compartment domains. Analysis of gap junction gene expression suggests that this functional subdivision of GJC may be mediated by the differential expression of the connexin gene family. The temporal-spatial pattern of connexin gene expression during mouse embryogenesis is highly suggestive of a role for gap junctions in inductive interactions, being regionally restricted in distinct developmentally significant domains. Using reverse genetic approaches to manipulate connexin gene function, direct evidence has been obtained for the connexin 43 (Cx43) gap junction gene playing a role in mammalian development. The challenges in the future are the identification of the target cell populations and the cell signaling processes in which Cx43-mediated cell-cell interactions are critically required in mammalian development. Our preliminary observations suggest that neural crest cells may be one such cell population.

Animals↗
PubMedDate not supplied

[Animal ontogenetic cell signaling pathways by the example of Notch cascade of Drosophila melanogaster].

Intercellular communications are coordinated in developing vertebrates and invertebrates embryos by a few signaling pathways. Structural and functional components of the pathways are encoded by cascade of genes. The signal transduction from cell surface to the nucleus is the common feature of these pathways. It is initiated by interaction of secreted ligand (signal) with the outer segment of transmembrane receptor. Then, activation of the intracellular segment of receptor provides modification of signal transducers in cytoplasm including transcription factors that regulates expression of target genes. Cell signal transduction development is conserved between species. In individual organism signal pathways provide various responses due to a time or spatial disjunction of gene expression. Morphogenetic features, genetic structure and signal transduction sequence of events are considered by the example of Notch cascade of Drosophila melanogaster.

Animals↗
PubMed2006

Spatial and temporal profiles for anti-inflammatory gene expression in leukocytes during a resolving model of peritonitis.

The recent appreciation of the role played by endogenous counterregulatory mechanisms in controlling the outcome of the host inflammatory response requires specific analysis of their spatial and temporal profiles. In this study, we have focused on the glucocorticoid-regulated anti-inflammatory mediator annexin 1. Induction of peritonitis in wild-type mice rapidly (4 h) produced the expected signs of inflammation, including marked activation of resident cells (e.g., mast cells), migration of blood-borne leukocytes, mirrored by blood neutrophilia. These changes subsided after 48-96 h. In annexin 1(null) mice, the peritonitis response was exaggerated ( approximately 40% at 4 h), with increased granulocyte migration and cytokine production. In blood leukocytes, annexin 1 gene expression was activated at 4, but not 24, h postzymosan, whereas protein levels were increased at both time points. Locally, endothelial and mast cell annexin 1 gene expression was not detectable in basal conditions, whereas it was switched on during the inflammatory response. The significance of annexin 1 system plasticity in the anti-inflammatory properties of dexamethasone was assessed. Clear induction of annexin 1 gene in response to dexamethasone treatment was evident in the circulating and migrated leukocytes, and in connective tissue mast cells; this was associated with the steroid failure to inhibit leukocyte trafficking, cytokine synthesis, and mast cell degranulation in the annexin 1(null) mouse. In conclusion, understanding how inflammation is brought under control will help clarify the complex interplay between pro- and anti-inflammatory pathways operating during the host response to injury and infection.

Animals↗
PubMed2000

Differentiation and histological analysis of embryonic stem cell-derived neural transplants in mice.

We report here that neural transplantation of in vitro-differentiated embryonic stem (ES) cells provides a versatile strategy for gene transfer into the central nervous system. ES cells were subjected to an optimized in vitro differentiation protocol to obtain embryoid bodies. These aggregates were stereotaxically transplanted into the brain of recipient adult mice, where they followed a strictly controlled differentiation pattern and eventually formed mature neural grafts. A marker gene, introduced into the ROSA26 locus allowed for precise determination of the fate of the descendants of the transplanted embryoid bodies and revealed that not only neurons but also astrocytes, oligodendrocytes and even microglial cells were graft-derived. Evaluation of long-term experiments showed viable grafts with a stable transgene expression and proved that this approach provides a tool for reliable gene expression within a spatially delimited area of neural tissue.

Animals↗
PubMed1997

Mechanisms of evolutionary changes in timing, spatial expression, and mRNA processing in the msp130 gene in a direct-developing sea urchin, Heliocidaris erythrogramma.

Developmental processes associated with skeletogenesis differ in the direct-developing sea urchin Heliocidaris erythrogramma from that in Heliocidaris tuberculata and other indirect-developing species. In H. erythrogramma, the differences include ingression of a much higher number of mesenchyme cells, failure of the cells to form the typical ring pattern of cells prior to the onset of skeletogenesis, a significantly reduced larval skeleton, and a delay in timing of expression of the skeletogenic cell-restricted gene msp130. We report that the heterochronic change in msp130 expression is regulated at the level of transcription. By transient expression of reporter constructs containing msp130 promoter regions from direct- and indirect-developing species, we found that this evolutionary change in regulation is consistent with changes in the timing of action of trans-acting factors in skeletogenic mesenchyme cells. We further used these experiments to show that the H. erythrogramma promoter contains elements required for correct spatial expression in the primary mesenchyme cells of an indirect-developing host. We finally show that alternate processing of H. erythrogramma msp130 is thus far specific to this species and not an aspect of adult skeletogenesis.

Alternative Splicing↗
PubMed2004

Direct visualization of electroporation-assisted in vivo gene delivery to tumors using intravital microscopy - spatial and time dependent distribution.

BACKGROUND: Electroporation is currently receiving much attention as a way to increase drug and DNA delivery. Recent studies demonstrated the feasibility of electrogene therapy using a range of therapeutic genes for the treatment of experimental tumors. However, the transfection efficiency of electroporation-assisted DNA delivery is still low compared to viral methods and there is a clear need to optimize this approach. In order to optimize treatment, knowledge about spatial and time dependency of gene expression following delivery is of utmost importance in order to improve gene delivery. Intravital microscopy of tumors growing in dorsal skin fold window chambers is a useful method for monitoring gene transfection, since it allows non-invasive dynamic monitoring of gene expression in tumors in a live animal. METHODS: Intravital microscopy was used to monitor real time spatial distribution of the green fluorescent protein (GFP) and time dependence of transfection efficiency in syngeneic P22 rat tumor model. DNA alone, liposome-DNA complexes and electroporation-assisted DNA delivery using two different sets of electric pulse parameters were compared. RESULTS: Electroporation-assisted DNA delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz was superior to other methods and resulted in 22% increase in fluorescence intensity in the tumors up to 6 days post-transfection, compared to the non-transfected area in granulation tissue. Functional GFP was detected within 5 h after transfection. Cells expressing GFP were detected throughout the tumor, but not in the surrounding tissue that was not exposed to electric pulses. CONCLUSIONS: Intravital microscopy was demonstrated to be a suitable method for monitoring time and spatial distribution of gene expression in experimental tumors and provided evidence that electroporation-assisted gene delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz is an effective method, resulting in early onset and homogenous distribution of gene expression in the syngeneic P22 rat tumor model.

Animals↗