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991.
Han N Shi Z Zhang K Gao X Zheng Z Gong P Guo Y Huang S Zhang F 《Cellular and molecular neurobiology》2011,31(5):695-700
Discs-large-related 3 (DLG3), a member of the membrane-associated guanylate kinases (MAGUKs) protein family, playing an important
role in regulating NMDA signal pathway and contributing to synaptic plasticity, may have an influence on the susceptibility
of non-syndromic mental retardation (NSMR). To investigate the possible genetic contribution of DLG3 gene to the NSMR of Chinese Han population, we performed an association study of 556 subjects (118 NSMR, 116 borderline NSMR,
and 322 controls in 275 males and 281 females) from Qin-Ba mountain region of Shaanxi province in the northwest of China by
five common SNPs in the gene. The results showed that there was no positive association between the genetic variations of
DLG3 and NSMR. In conclusion, the results of this study indicated that DLG3 did not associate with NSMR in Chinese Han population; however, further studies are needed. 相似文献
992.
Gong P Zhang F Lei X Wu X Chen D Zhang W Zhang K Zheng A Gao X 《Cellular and molecular neurobiology》2011,31(4):519-526
Reasoning skill is an advanced cognitive ability which is needed for drawing inferences from given information. It is well
known that the ability depends on the neural network of the frontal and parietal brain regions. In this study, we hypothesized
that some genes involved in neurotransmitter systems were related to reasoning skill. To confirm this hypothesis, we examined
the effects of 13 genes (BDNF, NRSF, COMT, DBH, DRD
2
, DRD
3
, DAT
1
, MAOA, GRM
1, GRIN2B, TPH
2
, 5-HT
2A
, and 5-HT
6
) in neurotransmitter systems on the non-verbal reasoning and verbal reasoning skills. The results indicated there were on
significant effects of the 17 functional variants of these genes on the performance of non-verbal reasoning and verbal analogical
reasoning skills (χ2 > 3.84, df = 1, P > 0.05). This study suggests that some of the functional variations in BDNF, COMT, DBH, DRD
2
, DRD
3
, MAOA, 5-HT
2A
, 5-HT
6
, GRM
1
, and GRIN2B have no observable effects on the certain reasoning skills in a young healthy Chinese Han population. 相似文献
993.
Heparan sulfate (HS), a polysaccharide ubiquitously expressed in animals, is essential for development and homeostasis. Degradation of HS by heparanase, an endoglucuronidase, may affect pathophysiological function. Expression of the heparanase gene has been found elevated in a number of pathological conditions. The goal of this work was to investigate the impact of heparanase on expression of other genes. DNA microarray analysis revealed that 1, 042 genes in the cortex and 1,039 genes in the thalamus are up- or down-regulated more than 2-fold in mouse brain overexpresssing human heparanase. Of these genes, two of the early growth response genes, Egr1 and Egr2, are substantially upregulated in the cortex, but essentially unchanged in the thalamus. RT-PCR analysis demonstrated a significant increase of Egr2, but a minor increase of Egr1, in human embryonic kidney cells stably overexpressing heparanase. The upregulated expression of Egr genes is also observed in hepatoma cells with upregulated expression of heparanase. Earlier studies reported that Egr1 induced heparanase expression; our findings suggest a possible reciprocal regulation of Egr and heparanase expression. Furthermore, overexpression of heparanase influenced expression of most genes involved in heparan sulfate proteoglycan biosynthesis, albeit to a different degree in the cortex and thalamus of the transgenic mice. 相似文献
994.
We present a study on the rupture behavior of single NIH 3T3 mouse fibroblasts under tension using micropipette aspiration. Membrane rupture was characterized by breaking and formation of an enclosed membrane linked to a tether at the cell apex. Three different rupture modes, namely: single break, initial multiple breaks, and continuous multiple breaks, were observed under similar loading condition. The measured mean tensile strengths of plasma membrane were 3.83 ± 1.94 and 3.98 ± 1.54mN/m for control cells and cells labeled with TubulinTracker, respectively. The tensile strength data was described by Weibull distribution. For the control cells, the Weibull modulus and characteristic strength were 1.86 and 4.40 mN/m, respectively; for cells labeled with TubulinTracker, the Weibull modulus and characteristic strength were 2.68 and 4.48 mN/m, respectively. Based on the experimental data, the estimated average transmembrane proteins-lipid cleavage strength was 2.64 ± 0.64 mN/m. From the random sampling of volume ratio of transmembrane proteins in cell membrane, we concluded that the Weibull characteristic of plasma membrane strength was likely to be originated from the variation in transmembrane proteins-lipid interactions. 相似文献
995.
Hong‐Sil Park Youngja Jung Hong‐Seog Park Mi Sook Hwang Eun‐Jeong Park Yong‐Gun Gong 《Journal of phycology》2011,47(4):821-828
Temperature is one of the major environmental factors that affect the distribution, growth rate, and life cycle of intertidal organisms, including red algae. In an effort to identify the genes involved in the high‐temperature tolerance of Porphyra, we generated 3,979 expression sequence tags (ESTs) from gametophyte thalli of P. seriata Kjellm. under normal growth conditions and high‐temperature conditions. A comparison of the ESTs from two cDNA libraries allowed us to identify the high temperature response (HTR) genes, which are induced or up‐regulated as the result of high‐temperature treatment. Among the HTRs, HTR2 encodes for a small polypeptide consisting of 144 amino acids, which is a noble nuclear protein. Chlamydomonas expressing the Porphyra HTR2 gene shows higher survival and growth rates than the wild‐type strain after high‐temperature treatment. These results suggest that HTR2 may be relevant to the tolerance of high‐temperature stress conditions, and this Porphyra EST data set will provide important genetic information for studies of the molecular basis of high‐temperature tolerance in marine algae, as well as in Porphyra. 相似文献
996.
Fleishman SJ Whitehead TA Strauch EM Corn JE Qin S Zhou HX Mitchell JC Demerdash ON Takeda-Shitaka M Terashi G Moal IH Li X Bates PA Zacharias M Park H Ko JS Lee H Seok C Bourquard T Bernauer J Poupon A Azé J Soner S Ovali SK Ozbek P Tal NB Haliloglu T Hwang H Vreven T Pierce BG Weng Z Pérez-Cano L Pons C Fernández-Recio J Jiang F Yang F Gong X Cao L Xu X Liu B Wang P Li C Wang C Robert CH Guharoy M Liu S Huang Y Li L Guo D Chen Y Xiao Y London N Itzhaki Z Schueler-Furman O Inbar Y Potapov V 《Journal of molecular biology》2011,414(2):289-302
The CAPRI (Critical Assessment of Predicted Interactions) and CASP (Critical Assessment of protein Structure Prediction) experiments have demonstrated the power of community-wide tests of methodology in assessing the current state of the art and spurring progress in the very challenging areas of protein docking and structure prediction. We sought to bring the power of community-wide experiments to bear on a very challenging protein design problem that provides a complementary but equally fundamental test of current understanding of protein-binding thermodynamics. We have generated a number of designed protein-protein interfaces with very favorable computed binding energies but which do not appear to be formed in experiments, suggesting that there may be important physical chemistry missing in the energy calculations. A total of 28 research groups took up the challenge of determining what is missing: we provided structures of 87 designed complexes and 120 naturally occurring complexes and asked participants to identify energetic contributions and/or structural features that distinguish between the two sets. The community found that electrostatics and solvation terms partially distinguish the designs from the natural complexes, largely due to the nonpolar character of the designed interactions. Beyond this polarity difference, the community found that the designed binding surfaces were, on average, structurally less embedded in the designed monomers, suggesting that backbone conformational rigidity at the designed surface is important for realization of the designed function. These results can be used to improve computational design strategies, but there is still much to be learned; for example, one designed complex, which does form in experiments, was classified by all metrics as a nonbinder. 相似文献
997.
Previous studies have shown that the late embryogenesis abundant (LEA) group 3 proteins significantly respond to changes in environmental conditions. However, reports that demonstrate their biological role, especially in Arabidopsis, are notably limited. This study examines the functional roles of the Arabidopsis LEA group 3 proteins AtLEA3-3 and AtLEA3-4 in abiotic stress and ABA treatments. Expression of AtLEA3-3 and AtLEA3-4 is upregulated by ABA, high salinity, and osmotic stress. Results on the ectopic expression of AtLEA3-3 and AtLEA3-4 in E. coli suggest that both proteins play important roles in resistance to cold stress. Overexpression of AtLEA3-3 in Arabidopsis (AtLEA3-3-OE) confers salt and osmotic stress tolerance that is characterized during germination and early seedling establishment. However, AtLEA3-3-OE lines show sensitivity to ABA treatment during early seedling development. These results suggest that accumulation of AtLEA3-3 mRNA and/or proteins may help heterologous ABA re-initiate second dormancy during seedling establishment. Analysis of yellow fluorescent fusion proteins localization shows that AtLEA3-3 and AtLEA3-4 are mainly distributed in the ER and that AtLEA3-3 also localizes in the nucleus, and in response to salt, mannitol, cold, or BFA treatments, the localization of AtLEA3-3 and AtLEA3-4 is altered and becomes more condensed. Protein translocalization may be a positive and effective strategy for responding to abiotic stresses. Taken together, these results suggest that AtLEA3-3 has an important function during seed germination and seedling development of Arabidopsis under abiotic stress conditions. 相似文献
998.
999.
1000.
Accelerated glucose metabolism leads to oxidative stress and DNA damage in cells; these effects are related to glucose toxicity. The precise mechanisms of glucose toxicity are still unclear. The aim of this work was to investigate the mechanism of poly(ADP‐ribose) polymerase 1 (PARP1), which is a DNA repair enzyme activated by high‐glucose‐induced oxidative stress, and its effect on glucose toxicity in HepG2 hepatocytes. HepG2 cells were cultured under normal (5.5 mM) or high (30 mM) glucose conditions for 4 days. PJ34, which is an inhibitor of PARP1, was used to determine the downstream effects of PARP1 activation. PARP1 activity in 30 mM‐glucose‐treated cells was more than that in 5.5 mM‐glucose‐treated cells, and the activity correlated with the increase in ROS generation and DNA damage. PJ34 suppressed PARP1 activation and prevented the high‐glucose‐induced suppression of SIRT1 and AMP‐activated protein kinase (AMPK) activity, which was similar to its effect on the restoration of intracellular nicotinamide adenine dinucleotide (NAD) content. Further, the phosphorylation of insulin receptor was attenuated in response to insulin stimulation under high glucose conditions, and PJ34 could reverse this effect. The results of transfection of HepG2 cells with PARP1 small interfering RNA were similar to those obtained by treatment of the cells with PARP1 inhibitor PJ34. These data suggest that high‐glucose‐induced PARP1 activation might play a role in glucose toxicity by down‐regulating SIRT1 and AMPK activity through NAD depletion and resulting in insulin insensitivity. J. Cell. Biochem. 112: 299–306, 2011. © 2010 Wiley‐Liss, Inc. 相似文献