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Brood cell size of Apis mellifera modifies the reproductive behavior of Varroa destructor

MAGGI, Matias; DAMIANI, Natalia; RUFFINENGO, Sergio; JONG, David De; PRINCIPAL, Judith; EGUARAS, Martin
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
55.71%
We undertook a field study to determine whether comb cell size affects the reproductive behavior of Varroa destructor under natural conditions. We examined the effect of brood cell width on the reproductive behavior of V. destructor in honey bee colonies, under natural conditions. Drone and worker brood combs were sampled from 11 colonies of Apis mellifera. A Pearson correlation test and a Tukey test were used to determine whether mite reproduction rate varied with brood cell width. Generalized additive model analysis showed that infestation rate increased positively and linearly with the width of worker and drone cells. The reproduction rate for viable mother mites was 0.96 viable female descendants per original invading female. No significant correlation was observed between brood cell width and number of offspring of V. destructor. Infertile mother mites were more frequent in narrower brood cells.; ANPCyT[07]

Efeito do tamanho da célula do favo de cria sobre a variabilidade morfológica das abelhas africanizadas (Apis mellifera) e sobre a infestação e reprodução do ácaro Varroa jacobsoni.; Effect of the brood comb cell size on the morphologic variability of the africanized honey bees (Apis mellifera) and on the infestation and reproduction of the mite Varroa jacobsoni.

Yapalucci, Giancarlo Antonio Piccirillo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/08/2001 PT
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65.83%
O presente trabalho teve como objetivo: 1. Determinar o efeito de diferentes tamanhos de células de cria de operárias (favos novos construídos naturalmente por abelhas Africanizadas e européias e favos velhos) sobre o peso e variabilidade morfológica das abelhas operárias emergentes em colônias de abelhas (Apis mellifera); 2. Examinar a influência das células de operárias de menor tamanho do favo velho em relação às células novas construídas por abelhas Africanizadas e às células de operárias construídas por abelhas européias (italianas e cárnicas) sobre a infestação e reprodução do ácaro Varroa jacobsoni. O trabalho foi todo realizado no Departamento de Genética da FMRP-USP em Ribeirão Preto. Foram utilizadas colônias de abelhas africanizadas do próprio apiário experimental (N=8). Foram usados neste experimento quatro tipos de favos: favo africanizado novo (FAFn), favo italiano novo (FITn), favo cárnico novo (FCAn) e favo velho africanizado (FVE) com as paredes das células engrossadas por efeito de muitas gerações de abelhas emergidas. Um total de três medidas foram feitas nas células de operárias de cada favo: diâmetro da célula (DC), profundidade da célula (PC) e peso da abelha emergente (PA). O volume da célula (VC) foi calculado a partir do DC e da PC. As abelhas...

The puc1 Cyclin Regulates the G1 Phase of the Fission Yeast Cell Cycle in Response to Cell Size

Martín-Castellanos, Cristina; Blanco, Miguel A.; de Prada, José M.; Moreno, Sergio
Fonte: The American Society for Cell Biology Publicador: The American Society for Cell Biology
Tipo: Artigo de Revista Científica
Publicado em /02/2000 EN
Relevância na Pesquisa
55.77%
Eukaryotic cells coordinate cell size with cell division by regulating the length of the G1 and G2 phases of the cell cycle. In fission yeast, the length of the G1 phase depends on a precise balance between levels of positive (cig1, cig2, puc1, and cdc13 cyclins) and negative (rum1 and ste9-APC) regulators of cdc2. Early in G1, cyclin proteolysis and rum1 inhibition keep the cdc2/cyclin complexes inactive. At the end of G1, the balance is reversed and cdc2/cyclin activity down-regulates both rum1 and the cyclin-degrading activity of the APC. Here we present data showing that the puc1 cyclin, a close relative of the Cln cyclins in budding yeast, plays an important role in regulating the length of G1. Fission yeast cells lacking cig1 and cig2 have a cell cycle distribution similar to that of wild-type cells, with a short G1 and a long G2. However, when the puc1+ gene is deleted in this genetic background, the length of G1 is extended and these cells undergo S phase with a greater cell size than wild-type cells. This G1 delay is completely abolished in cells lacking rum1. Cdc2/puc1 function may be important to down-regulate the rum1 Cdk inhibitor at the end of G1.

G2/M Arrest Caused by Actin Disruption Is a Manifestation of the Cell Size Checkpoint in Fission Yeast

Rupes̆, Ivan; Webb, Bradley A.; Mak, Alan; Young, Paul G.
Fonte: The American Society for Cell Biology Publicador: The American Society for Cell Biology
Tipo: Artigo de Revista Científica
Publicado em /12/2001 EN
Relevância na Pesquisa
55.78%
In budding yeast, actin disruption prevents nuclear division. This has been explained as activation of a morphogenesis checkpoint monitoring the integrity of the actin cytoskeleton. The checkpoint operates through inhibitory tyrosine phosphorylation of Cdc28, the budding yeast Cdc2 homolog. Wild-type Schizosaccharomyces pombe cells also arrest before mitosis after actin depolymerization. Oversized cells, however, enter mitosis uninhibited. We carried out a careful analysis of the kinetics of mitotic initiation after actin disruption in undersized and oversized cells. We show that an inability to reach the mitotic size threshold explains the arrest in smaller cells. Among the regulators that control the level of the inhibitory Cdc2-Tyr15 phosphorylation, the Cdc25 protein tyrosine phosphatase is required to link cell size monitoring to mitotic control. This represents a novel function of the Cdc25 phosphatase. Furthermore, we demonstrate that this cell size-monitoring system fulfills the formal criteria of a cell cycle checkpoint.

Regulation of Cell Size by Glucose Is Exerted via Repression of the CLN1 Promoter

Flick, Karin; Chapman-Shimshoni, Daphne; Stuart, David; Guaderrama, Marisela; Wittenberg, Curt
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/1998 EN
Relevância na Pesquisa
55.78%
Yeast cells are keenly sensitive to the availability and quality of nutrients. Addition of glucose to cells growing on a poorer carbon source elicits a cell cycle delay during G1 phase and a concomitant increase in the cell size. The signal is transduced through the RAS-cyclic AMP pathway. Using synchronized populations of G1 cells, we show that the increase in cell size required for budding depends upon CLN1 but not other G1 cyclins. This delay in cell cycle initiation is associated specifically with transcriptional repression of CLN1. CLN2 is not repressed. Repression of CLN1 is not limited to the first cycle following glucose addition but occurs in each cell cycle during growth on glucose. A 106-bp fragment of the CLN1 promoter containing the three MluI cell cycle box (MCB) core elements responsible for the majority of CLN1-associated upstream activation sequence activity is sufficient to confer glucose-induced repression on a heterologous reporter. A mutant CLN2 promoter that is rendered dependent upon its three MCB core elements due to inactivation of its Swi4-dependent cell cycle box (SCB) elements is also repressed by glucose. The response to glucose is partially suppressed by inactivation of SWI4, but not MBP1, which is consistent with the dependence of MCB core elements upon the SCB-binding transcription factor (SBF). We suggest that differential regulation of CLN1 and CLN2 by glucose results from differences in the capacity of SBF to activate transcription driven by SCB and MCB core elements. Finally...

Akt Maintains Cell Size and Survival by Increasing mTOR-dependent Nutrient Uptake

Edinger, Aimee L.; Thompson, Craig B.
Fonte: The American Society for Cell Biology Publicador: The American Society for Cell Biology
Tipo: Artigo de Revista Científica
Publicado em /07/2002 EN
Relevância na Pesquisa
55.69%
In multicellular organisms, constituent cells depend on extracellular signals for growth, proliferation, and survival. When cells are withdrawn from growth factors, they undergo apoptosis. Expression of constitutively active forms of the serine/threonine kinase Akt/PKB can prevent apoptosis upon growth factor withdrawal. Akt-mediated survival depends in part on the maintenance of glucose metabolism, suggesting that reduced glucose utilization contributes to growth factor withdrawal-induced death. However, it is unclear how restricting access to extracellular glucose alone would lead to the metabolic collapse observed after growth factor withdrawal. We report herein that growth factor withdrawal results in the loss of surface transporters for not only glucose but also amino acids, low-density lipoprotein, and iron. This coordinated decline in transporters and receptors for extracellular molecules creates a catabolic state characterized by atrophy and a decline in the mitochondrial membrane potential. Activated forms of Akt maintained these transporters on the cell surface in the absence of growth factor through an mTOR-dependent mechanism. The mTOR inhibitor rapamycin diminished Akt-mediated increases in cell size, mitochondrial membrane potential...

Growth Rate and Cell Size Modulate the Synthesis of, and Requirement for, G1-Phase Cyclins at Start

Schneider, Brandt L.; Zhang, Jian; Markwardt, J.; Tokiwa, George; Volpe, Tom; Honey, Sangeet; Futcher, Bruce
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /12/2004 EN
Relevância na Pesquisa
55.86%
In Saccharomyces cerevisiae, commitment to cell cycle progression occurs at Start. Progression past Start requires cell growth and protein synthesis, a minimum cell size, and G1-phase cyclins. We examined the relationships among these factors. Rapidly growing cells expressed, and required, dramatically more Cln protein than did slowly growing cells. To clarify the role of cell size, we expressed defined amounts of CLN mRNA in cells of different sizes. When Cln was expressed at nearly physiological levels, a critical threshold of Cln expression was required for cell cycle progression, and this critical threshold varied with both cell size and growth rate: as cells grew larger, they needed less CLN mRNA, but as cells grew faster, they needed more Cln protein. At least in part, large cells had a reduced requirement for CLN mRNA because large cells generated more Cln protein per unit of mRNA than did small cells. When Cln was overexpressed, it was capable of promoting Start rapidly, regardless of cell size or growth rate. In summary, the amount of Cln required for Start depends dramatically on both cell size and growth rate. Large cells generate more Cln1 or Cln2 protein for a given amount of CLN mRNA, suggesting the existence of a novel posttranscriptional size control mechanism.

Identification of Transcriptional and Metabolic Programs Related to Mammalian Cell Size

Miettinen, Teemu P.; Pessa, Heli K.J.; Caldez, Matias J.; Fuhrer, Tobias; Diril, M. Kasim; Sauer, Uwe; Kaldis, Philipp; Björklund, Mikael
Fonte: Cell Press Publicador: Cell Press
Tipo: Artigo de Revista Científica
Publicado em 17/03/2014 EN
Relevância na Pesquisa
55.8%
•Gene expression and metabolites levels relative to cell size are analyzed in liver•Mitochondrial gene expression is repressed cell-autonomously in larger cells•Cell size can be modulated by targeting mitochondria functions and lipid synthesis•Lipids are negative regulators of cell size because they promote cell proliferation

Auxin regulates SNARE-dependent vacuolar morphology restricting cell size

Löfke, Christian; Dünser, Kai; Scheuring, David; Kleine-Vehn, Jürgen
Fonte: eLife Sciences Publications, Ltd Publicador: eLife Sciences Publications, Ltd
Tipo: Artigo de Revista Científica
Publicado em 05/03/2015 EN
Relevância na Pesquisa
55.68%
The control of cellular growth is central to multicellular patterning. In plants, the encapsulating cell wall literally binds neighbouring cells to each other and limits cellular sliding/migration. In contrast to its developmental importance, growth regulation is poorly understood in plants. Here, we reveal that the phytohormone auxin impacts on the shape of the biggest plant organelle, the vacuole. TIR1/AFBs-dependent auxin signalling posttranslationally controls the protein abundance of vacuolar SNARE components. Genetic and pharmacological interference with the auxin effect on vacuolar SNAREs interrelates with auxin-resistant vacuolar morphogenesis and cell size regulation. Vacuolar SNARE VTI11 is strictly required for auxin-reliant vacuolar morphogenesis and loss of function renders cells largely insensitive to auxin-dependent growth inhibition. Our data suggests that the adaptation of SNARE-dependent vacuolar morphogenesis allows auxin to limit cellular expansion, contributing to root organ growth rates.

Size Control and Uniformity in Animal Cells

Ginzberg, Miriam Bracha
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation; text Formato: application/pdf
EN
Relevância na Pesquisa
45.94%
The homogeneity in cell size observed in many normal proliferating tissues, and the contrasting size disparities characteristic of several cancers, suggest that control mechanisms coordinate growth and cell cycle progression, but the existence of such mechanisms has not been firmly established. To address this problem, we used quantitative fluorescence microscopy to measure cell cycle position, total protein content, and the level of cell growth regulators such as phosphorylated ribosomal protein S6, in tandem in single cells. Measurements were made on large numbers of cells drawn from proliferating populations of both non-transformed and cancerous cells. Analysis of the joint distribution of cell size and cell cycle position revealed a control mechanism that restricts cells to a specified size range at several points in the cell cycle. Combining our measurements with live-cell imaging showed that this restriction is the result of a negative correlation between cell size and subsequent growth rate, indicating that cells can sense their own size and modulate their growth accordingly. We also observed cell-size-dependent adjustments of cell cycle length, which further reduced size variability. We then identified drugs that change the mean cell size without disrupting the cell-autonomous control mechanism...

Simultaneous regulation of cell size and chromosome replication in bacteria

Ho, Po-Yi; Amir, Ariel
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
65.84%
Bacteria are able to maintain a narrow distribution of cell sizes by regulating the timing of cell divisions. In rich nutrient conditions, cells divide much faster than their chromosomes replicate. This implies that cells maintain multiple rounds of chromosome replication per cell division by regulating the timing of chromosome replications. Here, we show that both cell size and chromosome replication may be simultaneously regulated by the long-standing initiator accumulation strategy. The strategy proposes that initiators are produced in proportion to the volume increase and is accumulated at each origin of replication, and chromosome replication is initiated when a critical amount per origin has accumulated. We show that this model maps to the incremental model of size control, which was previously shown to reproduce experimentally observed correlations between various events in the cell cycle and explains the exponential dependence of cell size on the growth rate of the cell. Furthermore, we show that this model also leads to the efficient regulation of the timing of initiation and the number of origins consistent with existing experimental results.

Unified changes in cell size permit coordinated leaf evolution

Brodribb, T.; Jordan, G.; Carpenter, R.
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
65.8%
THE processes by which the functions of interdependent tissues are coordinated as lineages diversify are poorly understood. HERE, we examine evolutionary coordination of vascular, epidermal and cortical leaf tissues in the anatomically, ecologically and morphologically diverse woody plant family Proteaceae. WE found that, across the phylogenetic range of Proteaceae, the sizes of guard, epidermal, palisade and xylem cells were positively correlated with each other but negatively associated with vein and stomatal densities. The link between venation and stomata resulted in a highly efficient match between potential maximum water loss (determined by stomatal conductance) and the leaf vascular system's capacity to replace that water. This important linkage is likely to be driven by stomatal size, because spatial limits in the packing of stomata onto the leaf surface apparently constrain the maximum size and density of stomata. WE conclude that unified evolutionary changes in cell sizes of independent tissues, possibly mediated by changes in genome size, provide a means of substantially modifying leaf function while maintaining important functional links between leaf tissues. Our data also imply the presence of alternative evolutionary strategies involving cellular miniaturization during radiation into closed forest...

Pole Age Affects Cell Size and the Timing of Cell Division in Methylobacterium extorquens AM1▿†

Bergmiller, Tobias; Ackermann, Martin
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /10/2011 EN
Relevância na Pesquisa
55.86%
A number of recent experiments at the single-cell level have shown that genetically identical bacteria that live in homogeneous environments often show a substantial degree of phenotypic variation between cells. Often, this variation is attributed to stochastic aspects of biology—the fact that many biological processes involve small numbers of molecules and are thus inherently variable. However, not all variation between cells needs to be stochastic in nature; one deterministic process that could be important for cell variability in some bacterial species is the age of the cell poles. Working with the alphaproteobacterium Methylobacterium extorquens, we monitored individuals in clonally growing populations over several divisions and determined the pole age, cell size, and interdivision intervals of individual cells. We observed the high levels of variation in cell size and the timing of cell division that have been reported before. A substantial fraction of this variation could be explained by each cell's pole age and the pole age of its mother: cell size increased with increasing pole age, and the interval between cell divisions decreased. A theoretical model predicted that populations governed by such processes will quickly reach a stable distribution of different age and size classes. These results show that the pole age distribution in bacterial populations can contribute substantially to cellular individuality. In addition...

Size diversity as an expression of phytoplankton community structure and the identification of its patterns on the scale of fjords and channels

Montecino, Vivian; Paredes, María Alejandra
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo de revista
EN
Relevância na Pesquisa
55.84%
Artículo de publicación ISI; Large microalgae, such as diatoms can generate high levels of biomass, unlike small phytoplankton components in the austral Fjords and estuarine systems of Chile. We propose a cell-size-based diversity index (H'(size)) measured as chlorophyll-a concentrations (Chl-a) to determine if the relationship between H'(size) versus Chl-a results in a hump-shaped distribution considering: (i) the intermediate disturbance hypothesis, (ii) phytoplankton size colonization strategies, and (iii) predictions of low H'(size) with high or low Chl-a levels and peaks in H'(size) with intermediate Chl-a levels. The functional responses of phytoplankton are tightly coupled to environmental conditions. Could, then, the relationship between H'(size) and Chl-a occur on a particular temporal/spatial scale? Herein, we analyze data from three CIMAR-Fiordos cruises performed between 2001 and 2002 within areas of different continental influence from 41 degrees to 47 degrees S. Phytoplankton samples were taken at different locations and depths, filtered to obtain Chl-a with and without size-fractionation (> 20 mu m, < 11 mu m), and then used to calculate H'(size). Total Chl-a (TChl-a) changed by two orders of magnitude between different cruises and areas. The small phytoplankton fraction (< 11 mu m) dominated with low TChl-a values (<= 1 mg m(-3))...

Environmental adaptation in stomatal size independent of the effects of genome size

Jordan, G.J.; Carpenter, R.J.; Koutoulis, A.; Price, A.; Brodribb, T.J.
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
Relevância na Pesquisa
55.87%
Cell sizes are linked across multiple tissues, including stomata, and this variation is closely correlated with genome size. These associations raise the question of whether generic changes in cell size cause suboptimal changes in stomata, requiring subsequent evolution under selection for stomatal size. We tested the relationships among guard cell length, genome size and vegetation type using phylogenetically independent analyses on 67 species of the ecologically and structurally diverse family, Proteaceae. We also compared how genome and stomatal sizes varied at ancient (among genera) and more recent (within genus) levels. The observed 60-fold range in genome size in Proteaceae largely reflected the mean chromosome size. Compared with variation among genera, genome size varied much less within genera (< 6% of total variance) than stomatal size, implying evolution in stomatal size subsequent to changes in genome size. Open vegetation and closed forest had significantly different relationships between stomatal and genome sizes. Ancient changes in genome size clearly influenced stomatal size in Proteaceae, but adaptation to habitat strongly modified the genome-stomatal size relationship. Direct adaptation to the environment in stomatal size argues that new proxies for past concentrations of atmospheric CO2 that incorporate stomatal size are superior to older models based solely on stomatal frequency.; Gregory J. Jordan...

Leaf Water Content and Palisade Cell Size

Canny, Martin; Huang, Cheng
Fonte: Cambridge University Press Publicador: Cambridge University Press
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.78%
• The palisade cell sizes in leaves of Eucalyptus pauciflora were estimated in paradermal sections of cryo-fixed leaves imaged in the cryo-scanning electron microscope, as a quantity called the cell area fraction (CAF). • Cell sizes were measured in d

Simultaneous regulation of cell size and chromosome replication in bacteria

Ho, Po-Yi; Amir, Ariel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/07/2015
Relevância na Pesquisa
55.81%
Bacteria are able to maintain a narrow distribution of cell sizes by regulating the timing of cell divisions. In rich nutrient conditions, cells divide much faster than their chromosomes replicate. This implies that cells maintain multiple rounds of chromosome replication per cell division by regulating the timing of chromosome replications. Here, we show that both cell size and chromosome replication may be simultaneously regulated by the long-standing initiator accumulation strategy. The strategy proposes that initiators are produced in proportion to the volume increase and is accumulated at each origin of replication, and chromosome replication is initiated when a critical amount per origin has accumulated. We show that this model maps to the incremental model of size control, which was previously shown to reproduce experimentally observed correlations between various events in the cell cycle and explains the exponential dependence of cell size on the growth rate of the cell. Furthermore, we show that this model also leads to the efficient regulation of the timing of initiation and the number of origins consistent with existing experimental results.

Cell size regulation in microorganisms

Amir, Ariel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.83%
Various rod-shaped bacteria such as the canonical gram negative Escherichia coli or the well-studied gram positive Bacillus subtilis divide symmetrically after they approximately double their volume. Their size at division is not constant, but is typically distributed over a narrow range. Here, we propose an analytically tractable model for cell size control, and calculate the cell size and inter-division time distributions. We suggest ways of extracting the model parameters from experimental data. Existing data for E. coli supports partial size control, and a particular explanation: a cell attempts to add a constant volume from the time of initiation of DNA replication to the next initiation event. This hypothesis explains how bacteria control their tight size distributions and accounts for the experimentally observed correlations between parents and daughters as well as the exponential dependence of size on growth rate.; Comment: typos in bibliography corrected

The Mitogen-Induced Increase in T Cell Size Involves PKC and NFAT Activation of Rel/NF-kB-Dependent c-myc Expression

Grumont, Raelene; Lock, Peter; Shannon, M Frances; Moore, Anna; Gerondakis, Steve; Mollinari, Michael
Fonte: Cell Press Publicador: Cell Press
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
65.77%
Cell growth during the G1 stage of the cell cycle is partly controlled by inducing c-myc expression, which in B cells is regulated by the NF-κB1 and c-Rel transcription factors. Here, we show that c-myc-dependent growth during T cell activation requires

Decreased endothelial size and connexin expression in rat caudal arteries during hypertension

Rummery, Nicole; McKenzie, Katja; Whitworth, Judith; Hill, Caryl
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.88%
Objectives: Hypertension is accompanied by endothelial dysfunction. The present study has investigated endothelial cell morphology and connexin expression in the caudal artery of the rat during the development of hypertension. Methods: A significant increase in systolic blood pressure was detected from 9 weeks of age in spontaneously hypertensive male rats (SHR) compared to normotensive Wistar-Kyoto (WKY) rats, reaching a maximum by 11-12 weeks of age. Immunohistochemistry was used to quantify cell size and expression of connexins (Cxs) 37, 40 and 43 in the endothelium of prehypertensive (3-week-old) and hypertensive (12-week-old) rats. Results: At 12 weeks, the size of endothelial cells and the expression of all three Cxs per endothelial cell were significantly less in SHR than WKY rats. At 3 weeks, there was no significant difference in cell size nor in the expression of Cxs 37 or 43; however, expression of Cx40 was significantly lower in SHR than in WKY rats. Between 3 and 12 weeks in WKY rats, there was no change in endothelial cell size, nor in the expression of Cxs 37, 40 and 43. In SHR, both cell size and Cx expression per endothelial cell were significantly decreased during the same developmental period, with a significant decrease in the density of Cx40 plaques. Conclusion: The development of hypertension in the SHR is accompanied by significant decreases in endothelial cell size and expression of Cx40...