Studies of the living embryo sacs of Torenia fournieri reveal that the actin cytoskeleton undergoes dramatic changes that correlate with nuclear migration within the central cell and the primary endosperm. Before pollination, actin filaments appear as short bundles randomly distributed in the cortex of the central cell. Two days after anthesis, they become organized into a distinct actin network.
View Article and Find Full Text PDFRoot growth is mainly determined by cell division and subsequent elongation in the root apical area. Components regulating cell division in root meristematic cells are largely unknown. Previous studies have identified rice (Oryza sativa) ROOT ARCHITECTURE ASSOCIATED1 (OsRAA1) as a regulator in root development.
View Article and Find Full Text PDFPeroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1alpha) is a multifunctional transcriptional regulator for the pathways controlling mitochondrial biogenesis, oxidative metabolism, and glucose homeostasis. Genetic studies have suggested that Gly482Ser polymorphism of the PGC-1alpha gene is associated with a higher risk of type 2 diabetes, obesity, and hypertension. Adiponectin is an antidiabetic and antiatherogenic adipocytokine that is specifically produced by adipose tissue, and the transcription of the adiponectin gene is regulated by PPARgamma.
View Article and Find Full Text PDFObjective: To investigate the effect of different habitats on rhubarb quality.
Method: The rhubarb samples from various parts of Qinghai province were analysed by fingerprint.
Results And Conclusion: The distribution and quality of wild Tangute rhubarb is better than Palmate sorrel rhubarb.
Purpose: In the central nervous system (CNS), increased mitochondrial DNA (mtDNA) damage is associated with aging and may underlie, contribute to, or increase the susceptibility to neurodegenerative diseases. Because of the focus on the retinal pigment epithelium (RPE) and choroid as tissue relevant to age-related macular degeneration (AMD), we examined young and aged RPE and choroid, harvested from rodent eyes, for DNA damage and for changes in selected DNA repair enzymes.
Methods: Immunohistochemical labeling and quantitative ELISA for the oxidative DNA damage marker, 8-hydroxy-2'-deoxy-guanosine (8-OHdG), were measured in young and aged rodent RPE and choroid.
Diabetic retinopathy involves an inflammatory response in the retina characterized by an increase in inflammatory cytokines and activation of microglia. The degree of microglia activation may influence the extent of retina injury following an inflammatory stimulus. Cytokines, released by activated microglia, regulate the influx of inflammatory cells to the damaged area.
View Article and Find Full Text PDFPlant Cell Physiol
November 2007
Although the results of some studies indicate that salt stress affects the organization of microtubules, it remains an open question whether microtubules play an active role in the plant's ability to withstand salt stress. In the present study, we showed that salt stress-induced wild-type Arabidopsis seedling roots display right-handed skewed growth and depolymerization of the cortical microtubules. The results of a long-term observational study showed that cortical microtubules depolymerized then reorganized themselves under salt stress.
View Article and Find Full Text PDFFen Zi Xi Bao Sheng Wu Xue Bao
June 2007
AtMAP65-1 gene was cloned from Arabidopsis genome. A plant expression vector containing AtMAP65-1-GFP fusion gene driven by 35S promoter was constructed and introduced into Arabidopsis by Agrobacterium infection. Under confocal laser scanning microscope (CLSM), it was found that in the light-induced opening guard cells AtMAP65-1 was distributed radiately from dorsal wall to ventral wall in a bundling way.
View Article and Find Full Text PDFWe characterize a novel, pollen-specific, microtubule-associated protein, SB401, found in Solanum berthaultii. This protein binds to and bundles taxol-stabilized microtubules and enhances tubulin polymerization in a concentration-dependent manner, particularly at lower temperatures. Electron microscopy revealed that the protein decorates the entire length of microtubules.
View Article and Find Full Text PDFPlant Cell Physiol
June 2007
The microtubule-associated protein AtMAP65-1 from Arabidopsis thaliana dimerizes and forms 25 nm cross-bridges between microtubules, but the exact mechanism is unknown. Here, we used the predicted three-dimensional structure of AtMAP65-1 as a basis for analyzing the actual cross-bridging in detail. Fold-recognition predicts that AtMAP65-1 contains four coiled-coil domains and a flexible extended loop.
View Article and Find Full Text PDFTo investigate whether or not the aging phenotype has increased vulnerability to axonal injury in vivo, we quantitated the loss of retinal ganglion cells (RGCs) after optic nerve crush. After crush, young animals lost 20% in 3 days and 50% of their RGCs in 7 days; however, old animals lost 40% in 3 days and 70% of their RGCs in 7 days. Our results showed that the time course in the loss of RGCs after crush in old mice is faster than that in young mice.
View Article and Find Full Text PDFIn Arabidopsis thaliana, the microtubule-associated protein AtMAP65-1 shows various functions on microtubule dynamics and organizations. However, it is still an open question about whether AtMAP65-1 binds to tubulin dimers and how it regulates microtubule dynamics. In present study, the tubulin-binding activity of AtMAP65-1 was investigated.
View Article and Find Full Text PDFBackground: Aging has been associated with widespread changes at the gene expression level in multiple mammalian tissues. We have used high density oligonucleotide arrays and novel statistical methods to identify specific transcriptional classes that may uncover biological processes that play a central role in mammalian aging.
Results: We identified 712 transcripts that are differentially expressed in young (5 month old) and old (25-month old) mouse skeletal muscle.
Three subtypes of beta-adrenoceptor, beta1, beta2 and beta3, are involved in the sympathetic nervous system, which plays an important role in the development of hypertension and hypertensive complications. These complications can include left ventricular hypertrophy and arterial stiffness, which are reported risk factors for cardiovascular diseases. We designed clinical trials to clarify the association between hypertensive complications and beta-adrenoceptor single nucleotide polymorphisms in essential hypertension.
View Article and Find Full Text PDFMicrotubule-associated proteins (MAPs) play important roles in the regulation of microtubule function in cells. We describe Arabidopsis thaliana MAP18, which binds to microtubules and inhibits tubulin polymerization in vitro and colocalizes along cortical microtubules as patches of dot-like structures. MAP18 is expressed mostly in the expanding cells.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
October 2012
The present study tested the hypothesis that the role of ERK in phasic and tonic contractile responses is declined by hindlimb unloading (HU) in rat femoral arteries. Male Wistar rats were randomised into HU and Control group (n=7). After 14d, the femoral arteries were isolated and cut into 3-mm ring segments.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
October 2012
The present study was to determine the effects of simulated microgravity (SM) on the pulmonary artery (PA) and aorta(TA), and to disclose the changes in pathophysiology of cardiovascular deconditioning(CVD) induced by SM and to explore the effects of NOS inhibitor (N-nitro-L-arginine methylester, L-NAME) on CVD. The high hemodynamics in pulmonary and systemic circulation of human bodies appeared during the initial period and super-regulatory phenomena under 6°head-down tilt bed.
View Article and Find Full Text PDFWe showed previously that primary keratinocytes selected for low desmoglein 3 (Dsg3) expression levels exhibited increased colony-forming efficiency and heightened proliferative potential relative to cells with higher Dsg3 expression levels, characteristics consistent with a more "stem/progenitor cell-like" phenotype. Here, we have confirmed that Dsg3(dim) cells derived from cultured primary human adult keratinocytes have comparability with alpha(6)(bri)/CD71(dim) stem cells in terms of colony-forming efficiency. Moreover, these Dsg3(dim) cells exhibit increased reconstituting ability in in vitro organotypic culture on de-epidermalized dermis (DED); they are small, actively cycling cells, and they express elevated levels of various p63 isoforms.
View Article and Find Full Text PDFZhongguo Wei Zhong Bing Ji Jiu Yi Xue
December 2006
Objective: To investigate the effects of the N omega-nitro-L-arginine methyl ester (L-NAME) on pulmonary artery of rats during 14 days simulated weightlessness.
Methods: Sixteen male Wistar rats were randomly divided into control group and tail-suspension (TP) group (each n=8). Vascular bathing technique was used to measure the contractile responses of rats pulmonary artery rings to phenylephrine (PE), dilatory responses to acetylcholine (Ach) and contractile response to PE in presence of L-NAME.
Although both clustering and identification of differentially expressed genes are equally essential in most microarray studies, the two tasks are often conducted without regard to each other. This is clearly not the most efficient way of extracting information. The main aim of this article is to develop a coherent statistical method that can simultaneously cluster and detect differentially expressed genes.
View Article and Find Full Text PDFComplete cellulose synthesis is required to form functional cell walls and to facilitate proper cell expansion during plant growth. AtCESA2 is a member of the cellulose synthase A family in Arabidopsis (Arabidopsis thaliana) that participates in cell wall formation. By analysis of transgenic seedlings, we demonstrated that AtCESA2 was expressed in all organs, except root hairs.
View Article and Find Full Text PDFJ Neurosci Res
December 2006
The phenotype of Wld(S) ("slow Wallerian degeneration") mice demonstrates prolonged survival of injured axons. However, whether the Wld(S) mutation delays degeneration of the neuronal cell body following axonal injury is unclear. We used a retrograde model of axonal transport failure in Wld(S) mice to test whether the mutant Wld(S) protein has any beneficial effect on the neuronal cell body.
View Article and Find Full Text PDFJ Mol Microbiol Biotechnol
March 2006
Pathogenic Yersinia species can evade phagocytosis by injecting virulence effectors that interfere with the phagocytic machinery of host cells. One of these virulence effectors is the protein tyrosine phosphatase YopH. Through its enzymatic activity, YopH interferes with the initial phagocytic process by affecting signalling for cytoskeletal rearrangements.
View Article and Find Full Text PDFThe breakage of fluorescence-labeled microtubules under irradiation of excitation light is found in our experiments. Its mechanism is studied. The results indicate that free radicals are the main reason for the photosensitive breakage.
View Article and Find Full Text PDFRan is an evolutionarily conserved eukaryotic GTPase. We previously identified a cDNA of TaRAN1, a novel Ran GTPase homologous gene in wheat (Triticum aestivum) and demonstrated that TaRAN1 is associated with regulation of genome integrity and cell division in yeast (Saccharomyces cerevisiae) systems. However, much less is known about the function of RAN in plant development.
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