长江河口及上海地区鱼类新记录种——长身鳜（英文）

2008年5月在崇明岛西端潮间带水域进行鱼类调查时,发现一尾长江河口及上海地区的鱼类新记录种——长身鳜,隶属鲈形目鮨科。主要特征如下：体较细长,近似圆筒形;头长,稍平扁。吻尖。口裂大,下颌明显突出;上颌达眼下方。前鳃盖骨后缘有10枚细锯齿,腹缘有向前倾斜的鳃盖骨棘2枚。鳃盖后端有1枚扁平棘,其上端有较小的短棘1枚。体黄褐色,头背和体侧具不规则的黑点和黑斑。近数十年来由于过度捕捞和水环境污染等原因,导致其资源量急剧减少,已被我国列入濒危动物红皮书。目前,关于长身鳜的资源状况研究十分薄弱,尤其是其繁殖习性、食性和发育等生物学特征研究还未见报道。因此,亟待开展此方面的研究和保护工作。     

治疗酶的研究进展

随着生物技术和现代药剂学研究的进展,酶类药物的应用取得了快速发展,已成为生物药物的一个重要门类。以下对治疗用酶的新品种、作用机理和新技术在治疗酶中的应用、酶作为药物靶点的应用等进行了回顾,并对未来治疗酶的发展方向进行了讨论。     

紫云英根际微生物碳源利用多样性研究

为探究绿肥根际调控效果的原因,采用碳素利用法-BIOLOG生态版,分析紫云英根际微生物种群结构和功能多样性。结果表明:紫云英根际土壤微生物总活性比非根际高,其主要贡献者是以氨基酸、糖类、酯类和醇类四大碳源为生的微生物,而与以磷酸盐、羧酸和胺类为碳源的微生物关系不大。进一步分析发现:紫云英根际产生了以α-酮丁酸、2-羟基安息香酸、4-羟基安息香酸、D-半乳糖醛酸、α-环式糊精、D-木糖、β-甲基-D-葡萄糖、D-甘露醇和L-精氨酸作为碳源的新微生物种群,完全抑制了以γ-羟基丁酸和苯乙基胺为碳源的微生物种群活性;根泌物抑制了以D-苹果酸、衣康酸和肝糖为碳源的微生物活性,而对以D-化纤二糖、N-乙酰基-D-葡萄胺、丙酮酸甲酯、吐温40、吐温80、L-苯基丙氨酸、L-天门酰胺酸和腐胺为碳源的微生物有促进作用,但对以D-氨基葡糖酸、α-D-乳糖和I-赤藻糖醇为碳源的微生物活性无显著影响;另外,即使是以同一类物质为碳源的微生物种群,在紫云英根际的表现也不完全一样,如以D-乳酸γ-内酯和L-丝氨酸为碳源的可快速培养微生物受到抑制,可慢速培养的微生物活性则有提高,而以甘氨酰基-L-谷氨酸为碳源的微生物的表现正好与之相反。     

Molecular mechanisms of projection neuron production and maturation in the developing cerebral cortex

The cerebral cortex is a brain structure unique to mammals and highly adapted to process complex information. Through multiple developmental steps, the cerebral cortex is assembled as a huge diversity of neurons comprising a complex laminar structure, and with both local and long-distance connectivity within the nervous system. Key processes must take place during its construction, including: (i) regulation of the correct number of neurons produced by progenitor cells, (ii) temporal and spatial generation of neuronal diversity, and (iii) control of neuron migration and laminar positioning as well as terminal differentiation within the mature cortex. Here, we seek to highlight recent cellular and molecular findings underlying these sequential steps of neurogenesis, cell fate specification and migration during cortical development, with particular emphasis on cortical projection neurons.     

In vivo upregulation of nitric oxide synthases in healthy rats

Periodic acceleration (pGz), sinusoidal motion of the whole body in a head–foot direction in the spinal axis, is a novel noninvasive means for cardiopulmonary support and induction of pulsatile shear stress. pGz increases plasma nitrite levels, in vivo and in vitro. Additionally, pGz confers cardioprotection in models of ischemia reperfusion injury. We hypothesize that pGz may also confer a cardiac phenotypic change by upregulation of the expression of the various NO synthase (NOS) isoforms in vivo. pGz was applied for 1 h to awake restrained male rats at 2 frequencies (360 and 600 cpm) and acceleration (Gz) of ±3.4 m/s². pGz did not affect arterial blood gases or electrolytes. pGz significantly increased total nitrosylated protein levels, indicating increased NO production. pGz also increased mRNA and protein levels of eNOS and nNOS, and phosphorylated eNOS in heart. pGz increased Akt phosphorylation (p-AKT), but not total Akt, or phosphorylated ERK1/2. Inducible (i) NOS levels were undetectable with or without pGz. Immunoblotting revealed the localization of nNOS, exclusively in cardiomyocyte, and pGz increased its expression. We have demonstrated that pGz changes myocardial NOS phenotypes. Such upregulation of eNOS and nNOS was still evident 24 h after pGz. Further studies are needed to understand the biochemical and biomechanical signal transduction pathway for the observed NOS phenotype changed induced by pGz.     

A functional analysis of N-glycosylation-related genes on sialylation of recombinant erythropoietin in six commonly used mammalian cell lines

Significant efforts have been made to improve the sialylation of recombinant glycoproteins with the aim of extending their in vivo circulation time. Here, we report a systematic functional analysis of 31 N-glycosylation-related genes on sialylation of recombinant EPO in six cell lines. BHK and CHO cells were found to sialylate recombinant EPO most effectively. None of the 31 genes, individually or in combination, was able to improve EPO sialylation in these cells. HEK293, Cos-7 and 3T3 cells showed intermediate sialylation capabilities, whereas NS0 cells sialylated recombinant EPO poorly. Overexpression of ST6GalI, ST3GalIII or ST3GalIV, but not ST3GalVI, was able to improve EPO sialylation in these four cell lines. qRT-PCR experiments revealed that ST3GalIII and ST3GalIV are indeed under expressed in HEK293, 3T3 and NS0 cells. Co-expression of upstream glycogenes failed to synergize with these sialyltransferases to further enhance sialylation, suggesting that the upstream glycogenes are all expressed at sufficient levels.     

F-box Protein Arabidillo-1 Promotes Lateral Root Development by Depressing the Functioning of GA<Subscript>3</Subscript> in <Emphasis Type="Italic">Arabidopsis</Emphasis>

In Arabidopsis, Arabidillo-1 and Arabidillo-2 have great sequence homology to Dictyostelium and metazoan β–catenin/Armadillo, which are important to animal and Dictyostelium development. Arabidillo-1 and Arabidillo-2 promote lateral root formation redundantly in Arabidopsis. Here, we showed that gibberellins (GA₃) has a greater inhibitory effect on lateral root growth from the null mutant arabidillo-1 than from the wild type, suggesting that the mechanism for Arabidillo-1-regulated modulation of lateral root proliferation is associated with GA₃-metabolic or signaling pathways. Our yeast two-hybrid analysis demonstrated that Arabidillo-1 interacts with ASK2 and ASK11, and that ASK2 can bind with the F-box domain of Arabidillo-1. Therefore, Arabidillo-1 is involved in the ubiquitin/26S proteasome-mediated proteolytic pathway. Based on these results, we conclude that Arabidillo-1 can degrade some positive regulator of the GA₃ signaling pathway through selective protein degradation of ubiquitin/26S. Moreover, that process is believed to be the mechanism for Arabidillo-1 promotion of lateral root development in Arabidopsis.     

Floral ontogeny of Sinojackia xylocarpa (Styracaceae), with special reference to the development of the androecium

Using scanning electron microscopy, we studied the floral ontogeny of Sinojackia xylocarpa. There are 6–7 (–8) sepals. Sepal initiation is staggered; adaxial sepals arise later than abaxial and lateral ones. There are (5–) 6–7 (–8) petals, initiated simultaneously. Petals alternate with the sepals, and occasionally there are two petals instead of one between two sepals. The (10–) 12–14 (–16) stamens are initiated centripetally in two sets (whorls). These floral organ numbers deviate from those of the otherwise mostly pentamerous family Styracaceae. The ovary consists of three (rarely four) locules. In each of the locules, two rows of ovules are differentiated basipetally. Placentation is axile with (5–) 6 (–7) ovules in each locule. Ovules are unitegmic and are ascending with the micropyle directed downwards. Intra‐ovarian trichomes are present as in other representatives of Styracaceae and seem to be an apomorphic character of the family as they are absent in the closely related Symplocaceae and Diapensiaceae. Various levels of organ union occur in anthetic S. xylocarpa. The calyx is synsepalous and the ovary syncarpous. Possibly, the basal connation of petals and stamens is postgenital (and not congenital), but this needs further study. The outward curvature of the young anthers of the inner stamen whorl superficially simulates an obdiplostemonous androecium. However, the sequence of stamen initiation shows a diplostemonous pattern.     

Phenotypic analysis of the ccp1Δ and ccp1Δ-ccp1 mutant strains of Saccharomyces cerevisiae indicates that cytochrome c peroxidase functions in oxidative-stress signaling

Yeast cytochrome c peroxidase (CCP) efficiently catalyzes the reduction of H₂O₂ to H₂O by ferrocytochrome c in vitro. The physiological function of CCP, a heme peroxidase that is targeted to the mitochondrial intermembrane space of Saccharomyces cerevisiae, is not known. CCP1-null-mutant cells in the W303-1B genetic background (ccp1Δ) grew as well as wild-type cells with glucose, ethanol, glycerol or lactate as carbon sources but with a shorter initial doubling time. Monitoring growth over 10 days demonstrated that CCP1 does not enhance mitochondrial function in unstressed cells. No role for CCP1 was apparent in cells exposed to heat stress under aerobic or anaerobic conditions. However, the detoxification function of CCP protected respiring mitochondria when cells were challenged with H₂O₂. Transformation of ccp1Δ with ccp1^W191F, which encodes the CCP^W191F mutant enzyme lacking CCP activity, significantly increased the sensitivity to H₂O₂ of exponential-phase fermenting cells. In contrast, stationary-phase (7-day) ccp1Δ-ccp1^W191F exhibited wild-type tolerance to H₂O₂, which exceeded that of ccp1Δ. Challenge with H₂O₂ caused increased CCP, superoxide dismutase and catalase antioxidant enzyme activities (but not glutathione reductase activity) in exponentially growing cells and decreased antioxidant activities in stationary-phase cells. Although unstressed stationary-phase ccp1Δ exhibited the highest catalase and glutathione reductase activities, a greater loss of these antioxidant activities was observed on H₂O₂ exposure in ccp1Δ than in ccp1Δ-ccp1^W191F and wild-type cells. The phenotypic differences reported here between the ccp1Δ and ccp1Δ-ccp1^W191F strains lacking CCP activity provide strong evidence that CCP has separate antioxidant and signaling functions in yeast.