留学生组织学全英文教学的探索与实践

我教研室已承担留学生组织学教学多年,在对留学生进行组织学全英文授课的教学实践中,为了提高教学质量,我们从课程安排、教材选用、教学方法、教学手段以及考试与成绩等方面进行了的探索和改革,并对留学生教学中遇到的语言交流问题进行分析,总结了提高外语水平的经验.本文就留学生组织学教学的探索与实践作了介绍,以便大家互相交流经验,共同提高.     

Mapping of qGL7-2,a grain length QTL on chromosome 7 of rice

A residual heterozygous line(RHL)carrying a heterozygous segment between two SSR loci RM11 and RM134 on the rice chromosome 7 was selected from a set of recombinant inbred lines from the cross D50(javanica)/HB277(indica).The former parent produces much longer grains than the latter.Selfed progenies of this selection were analyzed genotypically(SSRs)and phenotypically(grain length).Grain length was discontinuously variable in the mapping populations,allowing for the placement of this QTL qGL7-2 within a～4.8 cM interval defined by RM351 and RM234.A set of new markers within this region were developed,which narrowed the QTL to a 278 kb region defined by the markers Indel1 and RM21945.This region contains 49 predicted genes.The results also suggest that the novel allele for grain length will be used for the application of marker assisted selection for the improvement of grain length.     

Laccase‐catalysed polymeric dye synthesis from plant‐derived phenols for potential application in hair dyeing: Enzymatic colourations driven by homo‐ or hetero‐polymer synthesis

Laccase efficiently catalyses polymerization of phenolic compounds. However, knowledge on applications of polymers synthesized in this manner remains scarce. Here, the potential of laccase-catalysed polymerization of natural phenols to form products useful in hair dyeing was investigated. All 15 tested phenols yielded coloured products after laccase treatment and colour diversity was attained by using mixtures of two phenolic monomers. After exploring colour differentiation pattern of 120 different reactions with statistical regression analysis, three monomer combinations, namely gallic acid and syringic acid, catechin and catechol, and ferulic acid and syringic acid, giving rise to brown, black, and red materials, respectively, were further characterized because such colours are commercially important for grey hair dyeing. Selected polymers could strongly absorb visible light and their hydrodynamic sizes ranged from 100 to 400 nm. Analyses of enzyme kinetic constants, liquid chromatography and electrospray ionization-mass spectrometry (ESI-MS) coupled with collision-induced dissociation MS/MS indicate that both monomers in reactions involving catechin and catechol, and ferulic acid and syringic acid, are coloured by heteropolymer synthesis, but the gallic acid/syringic acid combination is based on homopolymer mixture formation. Comparison of colour parameters from these three reactions with those of corresponding artificial homopolymer mixtures also supported the idea that laccase may catalyse either hetero- or homo-polymer synthesis. We finally used selected materials to dye grey hair. Each material coloured hair appropriately and the dyeing showed excellent resistance to conventional shampooing. Our study indicates that laccase-catalysed polymerization of natural phenols is applicable to the development of new cosmetic pigments.     

Association between polymorphisms of matrix metalloproteinase 11 (MMP-11) and Kawasaki disease in the Korean population

AimsThis study was conducted to investigate the associations between single nucleotide polymorphisms (SNPs) of matrix metalloproteinases (MMPs) and Kawasaki disease (KD) in the Korean population.Main methodsA total 0f 101 KD patients and 306 healthy controls were examined. MMP7 (rs10502001, G/A, Arg77His), MMP11 (rs738792, T/C, Ala38Val), MMP12 (rs652438, A/G, Ile357Val) and MMP26 (rs2499953, A/G, Lys43Glu) genes were genotyped from the genomic DNA using direct sequencing. The results were then analyzed using logistic regression models, adjusting for gender as covariates.Key findingsThe four SNPs were in Hardy–Weinberg equilibrium. Only the MMP11 polymorphism (rs738792) was associated with KD. The SNP (rs738792) showed a statistically significant association with KD in the codominant (OR = 1.61, 95% CI = 1.11–2.34, P = 0.011) and dominant (OR = 1.92, 95% CI = 1.21–3.06, P = 0.006) models. However, there was no association between polymorphisms of other MMP genes and KD.SignificanceOverall, the results of this study indicate that MMP11 polymorphism may be associated with KD in the Korean population.     

Transplantation of endothelial progenitor cells alleviates renal interstitial fibrosis in a mouse model of unilateral ureteral obstruction

AimsThe present study investigated whether transplantation of bone marrow-derived endothelial progenitor cells (BM-EPCs) in renal capillary network improves renal interstitial fibrosis in unilateral ureteral obstruction (UUO) model in mice.Main methodsEx vivo generated, characterized, and cultivated mice BM-EPCs were identified by their vasculogenic properties in vitro. BM-EPCs were labelled with carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) before transplantation. The animal models of UUO were used. Histological changes in renal tubular interstitium were observed with HE and Masson staining. The protein levels of vascular endothelial growth factor(VEGF), hypoxia inducible factor-1α (HIF-1α) and connective tissue growth factor (CTGF) were analyzed by western blotting and immunohistochemistry. Transforming growth factor-β1 (TGF-β1) was detected by immunohistochemistry. Peritubular capillary (PTC) density was determined by CD31 immunostaining.Key findingsTransplanted BM-EPCs were successfully incorporated into the capillary network in the obstructed kidney in vivo. UUO induced a significant decrease in VEGF levels and PTC density in the kidney tissue, which was accompanied by a significant increase in HIF-1α, CTGF and TGF-β1. Transplantation of BM-EPCs increased PTC density, VEGF expression and alleviated the development of renal interstitial fibrosis in UUO mice. No significant pathological changes were found in control mice.SignificanceThe reduction of PTC density and up-regulation of HIF-1α are the important mechanisms of interstitial fibrosis in UUO mice. BM-EPCs transplantation may increase the number of capillary density and alleviate the development of renal fibrosis in obstructive nephropathy in mice.     

MODIFIED VACUOLE PHENOTYPE1 Is an Arabidopsis Myrosinase-Associated Protein Involved in Endomembrane Protein Trafficking

We identified an Arabidopsis (Arabidopsis thaliana) ethyl methanesulfonate mutant, modified vacuole phenotype1-1 (mvp1-1), in a fluorescent confocal microscopy screen for plants with mislocalization of a green fluorescent protein-δ tonoplast intrinsic protein fusion. The mvp1-1 mutant displayed static perinuclear aggregates of the reporter protein. mvp1 mutants also exhibited a number of vacuole-related phenotypes, as demonstrated by defects in growth, utilization of stored carbon, gravitropic response, salt sensitivity, and specific susceptibility to the fungal necrotroph Alternaria brassicicola. Similarly, crosses with other endomembrane marker fusions identified mislocalization to aggregate structures, indicating a general defect in protein trafficking. Map-based cloning showed that the mvp1-1 mutation altered a gene encoding a putative myrosinase-associated protein, and glutathione S-transferase pull-down assays demonstrated that MVP1 interacted specifically with the Arabidopsis myrosinase protein, THIOGLUCOSIDE GLUCOHYDROLASE2 (TGG2), but not TGG1. Moreover, the mvp1-1 mutant showed increased nitrile production during glucosinolate hydrolysis, suggesting that MVP1 may play a role in modulation of myrosinase activity. We propose that MVP1 is a myrosinase-associated protein that functions, in part, to correctly localize the myrosinase TGG2 and prevent inappropriate glucosinolate hydrolysis that could generate cytotoxic molecules.The plant endomembrane system is a complex network of subcellular compartments that includes the endoplasmic reticulum (ER), Golgi apparatus, vacuole, plasma membrane, secretory vesicles, and numerous intermediary compartments. Protein trafficking through the endomembrane system requires specific cargo recognition and delivery mechanisms that are mediated by a series of highly specific targeting signals (Surpin and Raikhel, 2004), whose proper recognition is critical for the function of numerous downstream processes, such as floral development (Sohn et al., 2007), gravitropism (Kato et al., 2002; Surpin et al., 2003; Yano et al., 2003), abiotic stress tolerance (Zhu et al., 2002), autophagy (Surpin et al., 2003; Bassham., 2007), pathogen defense (Robatzek, 2007), and turgor pressure and growth (De, 2000).The importance of protein trafficking for plant survival was demonstrated by the identification of the essential Arabidopsis (Arabidopsis thaliana) gene VACUOLELESS1 (VCL1; Rojo et al., 2001). VCL1 was identified as a homolog of Saccharomyces cerevisiae VPS16, which is critical for yeast vacuole biogenesis. Knockouts of yeast VPS16 lack discernible vacuoles but survive despite their severe phenotype. The absence of vacuoles in Arabidopsis vcl1-1 mutants results in embryo lethality (Rojo et al., 2001). The essential nature of trafficking in plants was also demonstrated by insertional mutagenesis of syntaxin genes, where lethality was observed after disruption of single genes in families with highly homologous members (Lukowitz et al., 1996; Sanderfoot et al., 2001). Thus, despite large families of endomembrane components with many homologous genes, many are not redundant in Arabidopsis.Although embryo-lethal mutations provide critical data, it is difficult to obtain additional information. Less severe mutations have proven successful for functional genetics studies of endomembrane trafficking proteins. For example, point mutations in the KATAMARI1/MURUS3 (KAM1/MUR3; Tamura et al., 2005) and KATAMARI2/GRAVITROPISM DEFECTIVE2 (KAM2/GRV2; Tamura et al., 2007; Silady et al., 2008) genes lead to disruption of endomembranes, resulting in the formation of perinuclear aggregates containing organelles. Nonlethal trafficking disruptions have also been generated using chemical genomics, where small molecules were used to perturb trafficking of a soluble cargo protein (Zouhar et al., 2004) and localization of endomembrane markers (Surpin et al., 2005; Robert et al., 2008). Such studies have provided valuable clues about these essential cellular processes.In order to obtain less severe, viable mutants with defects in endomembrane protein trafficking, we previously identified point mutants with defects in localization of a tonoplast reporter protein, GFP:δ-TIP (Avila et al., 2003). Two hundred one putative mutants were grouped into four categories based on the nature of their defects. One unique mutant, cell shape phenotype1, was recently characterized as a trehalose-6-phosphate synthase with roles in regulation of plant architecture, epidermal pavement cell shape, and trichome branching (Chary et al., 2008).Here, we describe an endomembrane trafficking mutant categorized by perinuclear aggregates of GFP:δ-TIP fluorescence (Avila et al., 2003). We refer to this mutant as modified vacuole phenotype1-1 (mvp1-1). At least five endomembrane fusion proteins are partially relocalized to these structures. Positional cloning identified MVP1 as a myrosinase-associated protein (MyAP) localized previously to the tonoplast by proteomics (Carter et al., 2004). mvp1-1 mutants showed reduced endomembrane system functionality, as demonstrated by defects in growth, utilization of stored carbon, gravitropic responsiveness, salt sensitivity, and increased susceptibility to a fungal necrotroph. MVP1 interacted specifically with THIOGLUCOSIDE GLUCOHYDROLASE2 (TGG2), a known myrosinase protein in Arabidopsis, and the mvp1-1 mutation had a significant effect on nitrile production during glucosinolate hydrolysis, suggesting a role in myrosinase function. Furthermore, MVP1 may function in quality control of glucosinolate hydrolysis by contributing to the proper tonoplast localization of TGG2.     

The C-terminal zinc finger domain of Arabidopsis cold shock domain proteins is important for RNA chaperone activity during cold adaptation

Among the four cold shock domain proteins (CSDPs) identified in Arabidopsis thaliana, it has recently been shown that CSDP1 harboring seven CCHC-type zinc fingers, but not CSDP2 harboring two CCHC-type zinc fingers, function as a RNA chaperone during cold adaptation. However, the structural features relevant to this differing RNA chaperone activity between CSDP1 and CSDP2 remain largely unknown. To determine which structural features are necessary for the RNA chaperone activity of the CSDPs, the importance of the N-terminal cold shock domain (CSD) and the C-terminal zinc finger glycine-rich domains of CSDP1 and CSDP2 were assessed. The results of sequence motif-swapping and deletion experiments showed that, although the CSD itself harbored RNA chaperone activity, the number and length of the zinc finger glycine-rich domains of CSDPs were crucial to the full activity of the RNA chaperones. The C-terminal domain itself of CSDP1, harboring seven CCHC-type zinc fingers, also has RNA chaperone activity. The RNA chaperone activity and nuclei acid-binding property of the native and chimeric proteins were closely correlated with each other. Collectively, these results indicate that a specific modular arrangement of the CSD and the zinc finger domain determines both the RNA chaperone activity and nucleic acid-binding property of CSDPs; this, in turn, contributes to enhanced cold tolerance in plants as well as in bacteria.     

选择性雌激素受体调节剂

雌激素替代疗法（estrogen replacement therapy,ERT）是治疗绝经后综合征的首选治疗方案,但是长期应用导致子宫内膜增生、乳腺癌等。选择性雌激素受体调节剂主要通过ER亚型、共调节子、靶启动子、雌激素受体相关受体等机制实现其组织选择性,在发挥骨骼、心血管保护作用的同时,减少了对乳腺及生殖系统的副作用。目前,选择性雌激素受体调节剂的种类、作用的组织特异性及其临床应用在医学界引起广泛关注,具有广阔的发展前景。     

Rapid and transient response of soil respiration to rain

The influence of rainstorm on soil respiration of a mixed forest in southern New England, USA was investigated with eddy covariance, rain simulation and laboratory incubation. Soil respiration is shown to respond rapidly and instantaneously to the onset of rain and return to the prerain rate shortly after the rain stops. The pulse‐like flux, most likely caused by the decomposition of active carbon compounds in the litter layer, can amount to a loss of 0.18 t C ha^?1 to the atmosphere in a single intensive storm, or 5–10% of the annual net ecosystem production of midlatitude forests. If precipitation becomes more variable in a future warmer world, the rain pulse should play an important part in the transient response of the ecosystem carbon balance to climate, particularly for ecosystems on ridge‐tops with rapid water drainage.