深远海浮游动物生态学研究进展

深远海浮游生态系统依据水深的差别可以被划分为几个子系统,包括上层、中层、深层和深渊层等。目前大量的研究结果表明在海洋上层,由于光照、温度、海冰和营养盐补充等因素的影响,浮游生物群落往往呈现出显著的时空变化。但在海洋中层及更深的区域,传统观点认为随着水深的增加,海洋的理化环境趋向于稳定,在这一区域生态系统的时空变化要弱于海洋上层。同时受调查技术和经费的限制,人们对于这一广阔区域内浮游生态系统时空变化规律的认识要局限的多。随着我国海洋科学的发展和海洋强国战略的实施,海洋科学研究也逐渐由过去的以近海研究为主发展到当前的近海、边缘海和深远海研究协同发展。但与我国近海浮游生态学过去数十年间积累的大量研究成果相比,我国科学家对深远海,特别是中层、深层和深渊层浮游生态学方面的研究极为缺乏。从大洋浮游动物群落的垂直分布及其变化、种间关系与生态位分化、深海浮游动物群落在碳沉降和生物地球化学循环中的作用等多个角度全面总结了当前国内外深海浮游生态学的研究进展,同时介绍过去十余年来深海浮游生态学研究技术手段上的巨大进步,以期为今后国内同行的研究提供参考和借鉴。     

Vimentin is important in the neural differentiation of PC12 cells promoted by sialylation

Sialic acid modification is a kind of post-translational modification. To investigate the regulation effect of sialic acid on neural differentiation, we used CycloManN propanyl perac (CycloManN pro), a metabolic precursor of sialic acid, to treat PC12 cells. We noted that CycloManN pro indeed robustly promoted global sialylation detected by MAL II lectin blot in PC12 cells. Simultaneously, we interestingly found that the neurite outgrowth of PC12 cells was significantly promoted by the CycloManN pro treatment. The profile analysis of sialylated proteins showed that a protein band at 55KD was greatly enhanced especially in PC12L cells after CycloManN pro treatment. After enrichment with lectin MAL II, the proteins in this band were analyzed by mass spectrometry. The results showed that 23 proteins were in the band, but the score of vimentin was the highest among them. To investigate further the role of vimentin in the process of neurite differentiation, vimentin construct was transfected into PC12 cells. We interestingly observed that ectopic expression of vimentin significantly enhanced the neurite outgrowth induced by CycloManN pro. However, after three potential glycosylation sites (Ser-7, Thr-33, Ser-34:) of vimentin were mutated to alanine, overexpression of the mutated vimentin completely lost the enhancement activity for the neural differentiation even in the presence of CycloManN pro. Taken together, our study demonstrated that vimentin was important in the induction of neural differentiation by CycloManN pro.     

Saitohin Q7R polymorphism is associated with late‐onset Alzheimer's disease susceptibility among caucasian populations: a meta‐analysis

Saitohin (STH) Q7R polymorphism has been reported to influence the individual's susceptibility to Alzheimer's disease (AD); however, conclusions remain controversial. Therefore, we performed this meta‐analysis to explore the association between STH Q7R polymorphism and AD risk. Systematic literature searches were performed in the PubMed, Embase, Cochrane Library and Web of Science for studies published before 31 August 2016. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of the association using a fixed‐ or random‐effects model. Subgroup analyses, Galbraith plot and sensitivity analyses were also performed. All statistical analyses were performed with STATA Version 12.0. A total of 19 case–control studies from 17 publications with 4387 cases and 3972 controls were included in our meta‐analysis. The results showed that the Q7R polymorphism was significantly associated with an increased risk of AD in a recessive model (RR versus QQ+QR, OR = 1.27, 95% CI = 1.01–1.60, P = 0.040). After excluding the four studies not carried out in caucasians, the overall association was unchanged in all comparison models. Further subgroup analyses stratified by the time of AD onset, and the quality of included studies provided statistical evidence of significant increased risk of AD in RR versus QQ+QR model only in late‐onset subjects (OR = 1.56, 95% CI = 1.07–2.26, P = 0.021) and in studies with high quality (OR = 1.37, 95% CI = 1.01–1.86, P = 0.043). This meta‐analysis suggests that the RR genotype in saitohin Q7R polymorphism may be a human‐specific risk factor for AD, especially among late‐onset AD subjects and caucasian populations.     

Down-regulated LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/FZD5/Wnt/β-catenin axis

Prostate cancer is the second most frequent malignancy in men worldwide, and its incidence is increasing. Therefore, it is urgently required to clarify the underlying mechanisms of prostate cancer. Although the long non-coding RNA LINC00115 was identified as an oncogene in several cancers, the expression and function of LINC00115 in prostate cancer have not been explored. Our results showed that LINC00115 was significantly up-regulated in prostate cancer tissues, which was significantly associated with a poor prognosis for prostate cancer patients. Functional studies showed that knockdown LINC00115 inhibited cell proliferation and invasion. In addition, LINC00115 served as a competing endogenous RNA (ceRNA) through sponging miR-212-5p to release Frizzled Family Receptor 5 (FZD5) expression. The expression of miR-212-5p was noticeably low in tumour tissues, and FZD5 expression level was down-regulated with the knockdown of LINC00115. Knockdown LINC00115 inhibited the Wnt/β‑catenin signalling pathway by inhibiting the expression of FZD5. Rescue experiments further showed that LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/ FZD5/ Wnt/β-catenin axis. The present study provided clues that LINC00115 may be a promising novel therapeutic target for prostate cancer patients.     

青藏高原三个盐碱湖的产甲烷菌群和产甲烷代谢途径分析

【目的】分析青藏高原不同类型盐碱湖中的优势产甲烷菌群和优势产甲烷代谢途径。【方法】以不同盐度和植被类型的公珠错、昆仲错和无植被的兹格塘错的沉积物为研究对象,通过高通量测序和q PCR定量古菌16S r RNA多样性分析优势古菌类群;模拟原位盐浓度及p H,比较不同产甲烷底物(甲醇、三甲胺、乙酸和H_2/CO_2)富集沉积物的产甲烷速率,分析其优势产甲烷菌代谢类型。通过添加产甲烷抑制剂(2-溴乙烷磺酸盐),检测沉积物中产甲烷底物积累,确定不同盐碱湖中主要的产甲烷途径。【结果】昆仲错的优势菌群包括甲基/乙酸型的甲烷八叠球菌科(Methanosarcinaceae,11%),乙酸型的甲烷鬃菌科(Methanosaetaceae,7.9%)和氢型甲烷菌甲烷杆菌目(Methanomicrobiales,7.4%);公珠错和兹格塘错的优势菌群为甲烷鬃菌科(Methanosaetaceae)分别占15%和15.3%,及甲烷杆菌属(Methanobacterium)和甲基型的甲烷叶菌属(Methanolobus)。公珠错和昆仲错分别以乙酸和甲醇产甲烷速率最高,而兹格塘错从不同底物产甲烷速率无差异。抑制甲烷产生后,公珠错主要积累乙酸,昆仲错主要积累甲醇;兹格塘错不仅甲烷排放低,也无产甲烷物质显著积累。【结论】昆仲错沉积物中的甲烷主要来自甲醇,公珠错中的甲烷主要来自乙酸,而兹格塘错产甲烷和底物积累不活跃。因而推测高原盐碱湖主要的产甲烷途径和菌群可能与周围植被类型的相关性更高,而与盐度的直接相关性较低。     

Oviposition preferences and antennal size in carrion flies

Carrion-feeding flies use odours emanating from the decomposing corpse as cues for oviposition and are described as generalists because the larvae feed on the corpses of diverse species. Whereas several features of the corpse may influence the oviposition choices of these flies, it is not known whether there is a preference for a particular species of corpse. We provided carrion flies with ovipositional (and feeding) choices in a field experiment, in which various odour sources were presented simultaneously. We found novel evidence of broadly consistent choices of carrion by flies from four families. Traps baited with decaying fish flesh captured the greatest number of individuals, whereas traps baited with decaying pig liver typically attracted the least. We also asked whether individuals captured in the various baits vary in antennal size, perhaps reflecting different capacities for odour detection. There was a trend for individuals of Lucilia sericata Meigen (Diptera: Calliphoridae) and the platystomatid collected from the traps baited with pig liver to have significantly larger antennae, whereas individuals of Muscina stabulans (Fallen) (Diptera: Muscidae) captured in traps baited with marine fish flesh had relatively longer antennae for their body size. Our data reveal a more nuanced pattern of oviposition behaviour in these generalist carrion flies, which may reflect differences in their preference of carrion with different nutrients, and in their capacity to detect particular odours.     

Maternal serum-derived exosomal lactoferrin as a marker in detecting and predicting ventricular septal defect in fetuses

Among different types of congenital heart diseases, ventricular septal defect is the most frequently diagnosed type and is frequently missed in early prenatal screening programs. Herein, we explored the role of maternal serum-derived exosomes in detecting and predicting ventricular septal defect in fetuses in the early stage of pregnancy. A total of 104 pregnant women consisting of 52 ventricular septal defect cases and 52 healthy controls were recruited. TMT/iTRAQ proteomic analysis uncovered 15 maternal serum exosomal proteins, which showed differential expression between ventricular septal defect and control groups. Among these, four down-regulated proteins, lactoferrin, SBSN, DCD, and MBD3, were validated by Western blot. The protein lactoferrin was additionally verified by ELISA which was able to distinguish ventricular septal defects from controls with area under the ROC curve (AUC) 0.804 (p < 0.001). Our findings reveal that lactoferrin in maternal serum-derived exosomes may be a potential biomarker for non-invasive prenatal diagnosis of fetal ventricular septal defects.     

微流控芯片监测绿色荧光蛋白在枯草芽孢杆菌中的表达

目前主要使用激光共聚焦扫描显微镜观察绿色荧光蛋白的表达,但需要昂贵的仪器并耗费大量时间。本研究开发了一种新型激光诱导的微流芯片检测系统来监测绿色荧光蛋白在枯草芽孢杆菌中的表达。该系统主要由激光装置、光路系统、微流控芯片、光电倍增管和计算机处理系统等5部分组成。对该系统的测试结果显示,随着诱导强度的增强监测信号峰也随之增强,并且与激光共聚焦显微镜观察的结果一致。利用该芯片系统能够快速准确地筛选和鉴定用绿色荧光蛋白作为标记的细胞克隆,可以替代PCR鉴定方法。但该系统仅仅能够监测表达强度,不能够满足蛋白定位等高水平研究,因此,该系统适合应用于环境的微生物监测、药物筛选和其他无需观察蛋白定位等研究。     

绞股蓝法呢基焦磷酸合酶基因的克隆及其序列分析

目的:克隆并分析绞股蓝法呢基焦磷酸合酶(FPS)基因的全长序列。方法:参照罗汉果法呢基焦磷酸合酶基因,设计扩增绞股蓝FPS基因的3′RACE引物,采用3'RACE和5'RACE法克隆绞股蓝FPS基因全长cDNA。结果:获得绞股蓝FPS基因全长cDNA序列共1288个核苷酸,包含一个1026核苷酸的开放读框,编码342个氨基酸残基,推断该蛋白的相对分子质量为3.94×104。NCBI Blast结果显示绞股蓝FPS基因编码蛋白的氨基酸序列与已知的植物FPS氨基酸序列的同源性为91%~74%,核酸序列的同源性为88%~78%。结论:克隆了绞股蓝FPS基因全长cDNA序列,为进一步研究绞股蓝FPS基因的表达及三萜皂苷合成通路关键酶分子的进化奠定了基础。