Functional classifications of coastal barrier island vegetation

Abstract. Due to the complexity of coastal barrier vegetation, it is useful to apply a functional-type approach to assess the response of barrier island vegetation to climate change. In this paper, a simple clustering analysis is applied to a group of 19 plant associations, based on six plant attributes and six environmental constraints. This analysis results in the suggestion that the main division of the vegetation types at Virginia Coast Reserve is between herbaceous and woody types, which differs from the existing classification which recognizes three groups: xeric-mesic herbaceous, woody and hydric-halophytic herbaceous. Considerations about grouping plant functional types are also addressed in this paper. At a global scale, inclusion of barrier plant functional types may not be so important for the climate-change response of vegetation, but it may be necessary to consider these important systems for spatially explicit modelling of landscape responses.     

The E3 ubiquitin ligase NEDD4 is an LC3-interactive protein and regulates autophagy

The MAP1LC3/LC3 family plays an essential role in autophagosomal biogenesis and transport. In this report, we show that the HECT family E3 ubiquitin ligase NEDD4 interacts with LC3 and is involved in autophagosomal biogenesis. NEDD4 binds to LC3 through a conserved WXXL LC3-binding motif in a region between the C2 and the WW2 domains. Knockdown of NEDD4 impaired starvation- or rapamycin-induced activation of autophagy and autophagosomal biogenesis and caused aggregates of the LC3 puncta colocalized with endoplasmic reticulum membrane markers. Electron microscopy observed gigantic deformed mitochondria in NEDD4 knockdown cells, suggesting that NEDD4 might function in mitophagy. Furthermore, SQSTM1 is ubiquitinated by NEDD4 while LC3 functions as an activator of NEDD4 ligase activity. Taken together, our studies define an important role of NEDD4 in regulation of autophagy.     

Focal adhesion kinase maintains,but not increases the adhesion of dental pulp cells

Focal adhesion kinase (FAK) functions as a key enzyme in the integrin-mediated adhesion-signalling pathway. Here, we aimed to investigate the effects of FAK on adhesion of human dental pulp (HDP) cells. We transfected lentiviral vectors to silence or overexpress FAK in HDP cells ex vivo. Early cell adhesion, cell survival and focal contacts (FCs)-related proteins (FAK and paxillin) were examined. By using immunofluorescence, the formation of FCs and cytoskeleton was detected, respectively. We found that both adhesion and survival of HDP cells were suppressed by FAK inhibition. However, FAK overexpression slightly inhibited cell adhesion and exhibited no change in cell survival compared with the control. A thick rim of cytoskeleton accumulated and smaller dot-shaped FCs appeared in FAK knockdown cells. Phosphorylation of paxillin (p-paxillin) was inhibited in FAK knockdown cells, verifying that the adhesion was inhibited. Less cytoskeleton and elongated FCs were observed in FAK-overexpressed cells. However, p-paxillin had no significant difference compared with the control. In conclusion, the data suggest that FAK maintains cell adhesion, survival and cytoskeleton formation, but excessive FAK has no positive effects on these aspects.     

Phosphorylation of Pkp1 by RIPK4 regulates epidermal differentiation and skin tumorigenesis

Tissue homeostasis of skin is sustained by epidermal progenitor cells localized within the basal layer of the skin epithelium. Post‐translational modification of the proteome, such as protein phosphorylation, plays a fundamental role in the regulation of stemness and differentiation of somatic stem cells. However, it remains unclear how phosphoproteomic changes occur and contribute to epidermal differentiation. In this study, we survey the epidermal cell differentiation in a systematic manner by combining quantitative phosphoproteomics with mammalian kinome cDNA library screen. This approach identified a key signaling event, phosphorylation of a desmosome component, PKP1 (plakophilin‐1) by RIPK4 (receptor‐interacting serine–threonine kinase 4) during epidermal differentiation. With genome‐editing and mouse genetics approach, we show that loss of function of either Pkp1 or Ripk4 impairs skin differentiation and enhances epidermal carcinogenesis in vivo. Phosphorylation of PKP1's N‐terminal domain by RIPK4 is essential for their role in epidermal differentiation. Taken together, our study presents a global view of phosphoproteomic changes that occur during epidermal differentiation, and identifies RIPK‐PKP1 signaling as novel axis involved in skin stratification and tumorigenesis.     

SYBR Green I荧光RT-PCR检测犬瘟热方法的建立和应用

根据GenBank发表的犬瘟热病毒（CDV）的F基因序列，经过分析在F片段的保守区域内设计引物，建立了SYBR Green I荧光RT-PCR检测CDV的方法，并通过对厦门市宠物医院收集的临床发病和疑似发病的犬病料（包括眼分泌物、鼻拭子、唾液、血液、尿液等）的检测，结果表明，本研究建立的快速检测CDV的SYBR Green I荧光RT-PCR方法具有特异性强、灵敏度高、操作简便等优点，值得推广应用。     

Chimeric contribution of human extended pluripotent stem cells to monkey embryos ex vivo

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南海南沙海域沉积物中可培养微生物及其多样性分析

【目的】为了从南沙海域中分离获得微生物菌种资源，【方法】本文通过沉积物采样、可培养菌分离及16S rRNA鉴定，【结果】从22个站点的沉积物样品中获得349株细菌，分属于87个种。发现产芽孢细菌分布最广，并在10个站点的分离株中占多数；它们是Bacillus，Halobacillus，Brevibacillus，Paenibacillus，Pontibacillus和Thalassobacillus。其中芽孢杆菌（Bacillus）无论在数量上还是种类上都最多，分别属于34种，其中有8个可能的新种。此外，g-Proteobacteria是分离率较高的另一亚群；其中，假单胞菌（Pseudomonas），海杆菌（Marinobacter），食烷菌（Alcanivorax）属的细菌最多。统计还发现，在深度750~2000 m之间，低GC含量的细菌最丰富，而深度2000 m以下，分离株则全部为g-Proteobacteria。【结论】南沙沉积物可培养微生物中产芽孢细菌及 g-Proteobacteria比较丰富；其中，产芽孢细菌的多样性最高，具有进一步研究开发价值。     

A general method for chimerization of monoclonal antibodies by inverse polymerase chain reaction which conserves authentic N-terminal sequences.

Chimerization of antibodies (Ab) by cloning the V (variable) regions encoding the light and heavy chains with degenerate oligodeoxyribonucleotide primers matching to framework region 1 and to the joining regions, leads to Ab with altered amino acids at the N-terminus compared to those of the parental Ab. This is due to N-terminal framework 1 sequences in the expression vectors [Larrick et al., Bio/Technology 7 (1989) 937-938; Le Boeuf et al., Gene (1989) 371-377; Orlandi et al., Proc. Natl. Acad. Sci. USA 86 (1989) 3833-3837]. This might lead to Ab with altered affinity to the antigen due to interaction of framework sequences with complementarity determining regions. Moreover, some V regions may be refractory to cloning by this procedure. Here, we describe a method to circumvent these potential problems. The V regions for both chains of the Ab are cloned by inverse polymerase chain reaction (PCR) with primers matching the known constant region sequences of the Ab. After sequencing, PCR fragments corresponding to the V regions of both chains are inserted in-frame into appropriate expression vectors leading to Ab with unaltered N-terminal sequences after expression in mammalian cells. The procedure is illustrated with an Ab directed against the beta chain of the human interleukin-2 receptor.