High-altitude tree growth responses to climate change across the Hindu Kush Himalaya

兴都库什喜马拉雅地区高海拔树木生长对气候变化的响应 高海拔地区快速升温可能导致树木对温度响应更为敏感,而限制高海拔地区树木生长的关键气候因子以及气候变化对树木生长产生多大程度的影响尚不清楚。本研究在兴都库什喜马拉雅地区收集了73 个样点的树轮数据,包括3个优势属的树种(Abies属、Juniperus属和Picea属),样点海拔均在3000 m以上。 将时间动态规整(dynamic time warping)的方法用于建立亚区域年表,以考虑不同站点年表之间变化的同步 性。同时,定量分析了气候因子对树木生长的贡献以及树木生长与气候因子关系的时空动态。研究结果发现,73个站点年表可以聚为3类,且与其所处的生物气候区相对应,即西喜马拉雅地区,中东喜马拉雅地区和藏东南地区。在干旱的西喜马拉雅地区,树木生长与冬、春两季的降水呈正相关关系,而在湿润的藏东南地区,树木生长与冬季温度和春季降水呈正相关关系。树木生长受最低温度的影响最大,特别是冬季温度,其重要性从西到东呈现递增趋势。滑动窗口相关分析表明,在中西喜马拉雅地区,影响树木生长的冬季温度信号在减弱,然而在藏东南地区该信号随着1980年以来的快速升温而增强。本研究结果表明,若该地区升温持续,在西喜马拉雅地区可能会因变暖引起的水分亏缺而造成森林衰退,而在藏东南地区因树木生长得益于变暖而使得森林扩张。     

Macrophage migration inhibitory factor regulates joint capsule fibrosis by promoting TGF-β1 production in fibroblasts

Joint capsule fibrosis caused by excessive inflammation results in post-traumatic joint contracture (PTJC). Transforming growth factor (TGF)-β1 plays a key role in PTJC by regulating fibroblast functions, however, cytokine-induced TGF-β1 expression in specific cell types remains poorly characterized. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine involved in inflammation- and fibrosis-associated pathophysiology. In this study, we investigated whether MIF can facilitate TGF-β1 production from fibroblasts and regulate joint capsule fibrosis following PTJC. Our data demonstrated that MIF and TGF-β1 significantly increased in fibroblasts of injured rat posterior joint capsules. Treatment the lesion sites with MIF inhibitor 4-Iodo-6-phenylpyrimidine (4-IPP) reduced TGF-β1 production and relieved joint capsule inflammation and fibrosis. In vitro, MIF facilitated TGF-β1 expression in primary joint capsule fibroblasts by activating mitogen-activated protein kinase (MAPK) (P38, ERK) signaling through coupling with membrane surface receptor CD74, which in turn affected fibroblast functions and promoted MIF production. Our results reveal a novel function of trauma-induced MIF in the occurrence and development of joint capsule fibrosis. Further investigation of the underlying mechanism may provide potential therapeutic targets for PTJC.     

Synergistic Therapy of Doxorubicin with Cationic Anticancer Peptide L-K6 Reverses Multidrug Resistance in MCF-7/ADR Cancer Cells In Vitro via P-glycoprotein Inhibition

International Journal of Peptide Research and Therapeutics - Multidrug resistance (MDR) is one of the major obstacles to efficient chemotherapy against cancers, resulting from the overexpression of...     

Peptides YYGGEGSSSEQG and SESEM Inhibit TNF-α-Induced Smooth Muscle Cells Proliferation and Migration Through Their Bindings to TNF-α Receptor

International Journal of Peptide Research and Therapeutics - The peptides YYGGEGSSSEQG and SESEM derived from rice α-globulin have been reported to possess anti-atherosclerotic activity, but...     

Identification and expression analysis of lncRNA in seven organs of Rhinopithecus roxellana

Long non-coding RNA (lncRNA) represents a new direction to identify expression profiles and regulatory mechanisms in various organisms. Here, we report the first dataset of lncRNAs of the golden snub-nosed monkey (GSM), including 12,557 putative lncRNAs identified from seven organs. Compared with mRNA, GSM lncRNA had fewer exons and isoforms, and longer length. LncRNA showed more obvious tissue-specific expression than mRNA. However, for the top ten most abundant genes in each organ, mRNAs expression was more tissue-specific than lncRNAs. By identification of specifically expressed lncRNAs and mRNAs in each organ, it indicates that the expression of SEG-lncRNA (specifically expressed lncRNA) and SEG-mRNA (specifically expressed mRNA) had high correlation. In particular, combined our lncRNA and mRNA data, we identified 92 heart SEG-lncRNAs targeted ten mRNA genes in the oxidative phosphorylation pathway and upregulated the expression of these target genes such as ND4, ATP6, and ATP8. These may contribute to GSM adaption to its high-elevation environment. We also identified 171 liver SEG-lncRNAs, which targeted 27 genes associated with the metabolism of xenobiotics and leaded to high expression of these target genes in liver. These lncRNAs may play important roles in GSM adaptation to a folivory diet.

     

The involvement of α-proteobacteria Phenylobacterium in maintaining the dominance of toxic Microcystis blooms in Lake Taihu,China

Lake Taihu in China has suffered serious harmful cyanobacterial blooms for decades. The algal blooms threaten the ecological sustainability, drinking water safety, and human health. Although the roles of abiotic factors (such as water temperature and nutrient loading) in promoting Microcystis blooms have been well studied, the importance of biotic factors (e.g. bacterial community) in promoting and meditating Microcystis blooms remains unclear. In this study, we investigated the ecological dynamics of bacterial community, the ratio of toxic Microcystis, as well as microcystin in Lake Taihu. High-throughput 16S rRNA sequencing and principal component analysis (PCA) revealed that the bacteria community compositions (BCCs) clustered into three groups, the partitioning of which corresponded to that of groups according to the toxic profiles (the ratio of toxic Microcystis to total Microcystis, and the microcystin concentrations) of the samples. Further Spearman's correlation network showed that the α-proteobacteria Phenylobacterium strongly positively correlated with the toxic profiles. Subsequent laboratory chemostats experiments demonstrated that three Phenylobacterium strains promoted the dominance of the toxic Microcystis aeruginosa PCC7806 when co-culturing with the non-toxic PCC7806 mcyB⁻ mutant. Taken together, our data suggested that the α-proteobacteria Phenylobacterium may play a vital role in the maintenance of toxic Microcystis dominance in Lake Taihu.     

5种相思树和尾巨桉人工林土壤养分和酶活性特征

为揭示固氮树种土壤养分转化的酶学机制,对固氮树种[厚荚相思(Acacia crassicarpa)、黑木相思(A. melanoxylon)、卷荚相思(A.cincinnata)、大叶相思(A.auriculiformis)和马占相思(A.mangium)]及非固氮树种尾巨桉(Eucalyptusurophylla×E.grandis)人工林的土壤养分含量、酶活性及其相关性进行研究。结果表明,相思林40～60cm土层的pH均高于尾巨桉林;5种相思林土壤各土层的TP、TK含量均低于尾巨桉林,而20～40 cm土层的TC、TN含量均高于尾巨桉林,黑木相思林和马占相思林各土层的有效养分均显著高于尾巨桉林(P0.05)。0～10 cm土层中,相思林的土壤酸性磷酸酶和纤维素酶活性均高于尾巨桉林,大叶相思林的土壤脲酶、蔗糖酶、纤维素酶和芳基硫酸酯酶活性显著高于尾巨桉林(P0.05),卷荚相思林的土壤脲酶、纤维素酶、几丁质酶和淀粉酶活性显著高于尾巨桉林(P0.05)。相关分析结果表明,土壤脲酶、蔗糖酶和几丁质酶活性与AP显著负相关(P0.05),蔗糖酶和纤维素酶活性与NH4+-N显著负相关(P 0.05),脲酶、纤维素酶、芳基硫酸酯酶与土壤TK显著负相关(P0.05),几丁质酶活性与TN含量呈显著正相关(P0.05),土壤淀粉酶活性与NH4+-N呈显著正相关(P 0.05),过氧化氢酶活性与土壤TK含量呈显著正相关。可见,与尾巨桉人工林相比,在我国南方退化山地引种相思树可提高土壤关键酶的活性,对土壤有效养分具有明显改良作用,有利于退化地土壤的生态修复及人工林长期生产力的维持。     

蒙古黄芪病程相关蛋白AmPR-10于大肠杆菌不同载体的可溶性表达策略研究

蒙古黄芪病程相关蛋白（Astragalus membranaceus pathogenesis-related protein-10, AmPR-10）具有核酸酶活性,对黄芪生长发育及抗病机制具有重要意义。但从天然黄芪中提取蛋白质的传统方法成本较高,蛋白得率较少。研究首次利用大肠杆菌表达体系对AmPR-10进行可溶性外源表达,构建了3种重组子：①以pET28a为载体构建pET28a-AmPR-10;②以pET30a为载体构建pET30a-AmPR-10;③以pET30a为载体、大肠杆菌分子伴侣skp修饰构建pET30a-skp-AmPR-10。通过SDS-PAGE分析,目的蛋白可溶性表达量比较结果是：pET30a-skp-AmPR-10 > pET30a-AmPR-10 > pET28a-AmPR-10。由蛋白质三级结构模拟分析发现,载体pET-30a上的标签S-tag通过影响AmPR-10局部α螺旋构象而提高目标蛋白的可溶性表达,分子伴侣skp通过提高融合蛋白整体α螺旋比例进一步提升目标蛋白可溶性表达量。研究解决了目前从天然黄芪中提取蛋白操作复杂、提取量小的问题。同时,经测定,目的蛋白具有核酸酶活性,为外源AmPR-10相关活性研究提供了依据。     

Derivation and characterization of cell cultures from the skin of the Indo-Pacific humpback dolphin Sousa chinensis

The marine mammalian Indo-Pacific humpback dolphin, once widely lived in waters of the Indian to western Pacific oceans, has become an endangered species. The individual number of this dolphin has significantly declined in recent decades, which raises the concern of extinction. Direct concentration on laboratorial conservation of the genetic and cell resources should be paid to this marine species. Here, we report the successful derivation of cell lines form the skin of Indo-Pacific humpback dolphin. The cell cultures displayed the characteristics of fibroblast in morphology and grew rapidly at early passages, but showed obvious growth arrest at higher passages. The karyotype of the cells consisted of 42 autosomes and sex chromosomes X and Y. The immortalized cell lines obtained by forced expression of the SV40 large T-antigen were capable of proliferation at high rate in long-term culture. Immortalization and long-term culture did not cause cytogenetically observable abnormality in the karyotype. The cell type of the primary cultures and immortalized cell lines were further characterized as fibroblasts by the specific expression of vimentin. Gene transfer experiments showed that exogenetic genes could be efficiently delivered into the cells by both plasmid transfection and lentivirus infection. The cells derived from the skin of the Indo-Pacific humpback dolphin may serve as a useful in vitro system for studies on the effects of environmental pollutants and pathogens in habitats on the dolphin animals. More importantly, because of their high proliferation rate and susceptibility to lentivirus, these cells are potential ideal materials for generation of induced pluripotent stem cells.