Genetic Manipulation of Sex Ratio for the Large-Scale Breeding of YY Super-Male and XY All-Male Yellow Catfish (Pelteobagrus fulvidraco (Richardson))

Yellow catfish has become one of the most important freshwater aquaculture species in China. The mono-sex male yellow catfish has important application value in aquaculture because the male grows generally faster than the sibling females under the same conditions. This study has screened YY super-male and YY physiological female yellow catfish by sex reversal, gynogenesis, and progeny testing, which can help to achieve the large-scale production of YY super-male and XY all-male. From 2008 to 2010, about 123,000 YY super-male were produced, and about 81 million XY all-male fry were produced with 100 % male rate by random sampling. Therefore, these results indicate that YY super-male and YY physiological female yellow catfish can be viable and fertile. We conclude that the mono-sex breeding technique by YY super-male yellow catfish is stable and reliable, which has great potential for application in yellow catfish aquaculture.     

不同种类氮肥对土壤释放N2O的影响

用培养试验模拟研究了在正常水分 ( 2 2 % )、干旱 ( 1 2 % )和高含水量 ( 32 % )条件下 ,普通碳酸氢铵 (普碳 )、尿素及新型肥料长效碳酸氢铵 (长碳 )对土壤释放N2 O的影响 ;同时考察了土壤NO-3 的形成时间和形成量 .结果表明 ,农田中施加的无机氮肥是大气中N2 O的重要来源 ,而长碳与普碳和尿素相比 ,不但可以明显延后N2 O释放高峰期出现时间 ,而且大多数情况下可以显著减少其释放量 (P <0 .0 1 ) .在 5个月的监测期内 ,与普碳和尿素相比其减少N2 O释放的比例分别为 80 .2 3和 88.41 % ( 1 2 %含水量 ) ,40 .0 0和2 7.59% ( 2 2 %含水量 ) ,无减少作用和 45.88% ( 32 %含水量 ) .本研究结果提示长碳具有作为农田生态系统N2 O减排措施的巨大潜力 ,同时暗示在农业中用长碳代替目前普遍应用的普碳 ,可以减少地下水中NO-3 引起的污染 .     

Comparative proteomics analysis of silkworm hemolymph during the stages of metamorphosis via liquid chromatography and mass spectrometry

The silkworm is a lepidopteran insect that has an open circulatory system with hemolymph consisting of blood and lymph fluid. Hemolymph is not only considered as a depository of nutrients and energy, but it also plays a key role in substance transportation, immunity response, and proteolysis. In this study, we used LC‐MS/MS to analyze the hemolymph proteins of four developmental stages during metamorphosis. A total of 728 proteins were identified from the hemolymph of the second day of wandering stage, first day of pupation, ninth day of pupation, and first day as an adult moth. GO annotations and categories showed that silkworm hemolymph proteins were enriched in carbohydrate metabolism, proteolysis, protein binding, and antibacterial humoral response. The levels of nutrient, immunity‐related, and structural proteins changed significantly during development and metamorphosis. Some, such as cuticle, odorant‐binding, and chemosensory proteins, showed stage‐specific expression in the hemolymph. In addition, the expression of several antimicrobial peptides exhibited their highest level of abundance in the hemolymph of the early pupal stage. These findings provide a comprehensive proteomic insight of the silkworm hemolymph and suggest additional molecular targets for studying insect metamorphosis.     

一种重组人α1型干扰素突变体IFN-α1/86D的纯化与鉴定

本文研究了重组人α1型干扰素突变体IFN-α1/86D在摇瓶培养和分批发酵培养的重组大肠杆菌DH5α株中的表达动态,并采用阳离子交换层析和抗α1型干扰素单克隆抗体亲和层析的两步流程对其进行了纯化,得到SDS-PAGE纯及高效液相层析(HPLC)纯的IFN-α1/86D产品,共比活性为2.3×10~7单位/毫克蛋白。N端氨基酸序列测定的结果表明,纯化产品的纯度在95％以上,但其N端不均一,产品中含有两种N端序列正确的IFN-α1/86D活性分子,即约75％为去Met分子和约25％为带Met分子。     

鸡减蛋综合征病毒（EDSV—76）末端前体蛋白的基因结构分析

从中国发病鸡群中分离的鸡减蛋综合征病毒弱毒株ＡＡ－２,经常规方法提取其病毒核酸后,组建了完整的限制性内切酶ＰｓｔＩ及ＨｉｎｇⅢ水解片段的基因文库,并对其中ＨｉｎｄⅢ,－ＳａｃⅠ进行了序列测定。同源比较分析证明：其Ｌ链含编码病毒末端前体蛋白,容量为５８０个氨基酸残基的开放读码框架。     

基于不同零模型的点格局分析

在种群空间格局研究中,定量分析格局及其形成过程已成为生态学家的主要目标。在量化分析的众多方法中,点格局分析是最常用的方法,而在选择零模型时,完全空间随机模型以外的复杂零模型很少使用,实际上,这些零模型可能有助于认识格局的内在特征。为此,我们在研究实例中,选择完全空间随机模型(complete spatial randomness)、泊松聚块模型(Poisson cluster process)和嵌套双聚块模型(nested double-cluster process)对典型草原处于不同恢复演替阶段的羊草(Leymus chinensis)种群空间格局进行了分析。结果发现:完全空间随机模型仅能检测种群在不同尺度下的格局类型;而通过泊松聚块模型和嵌套双聚块模型检验表明,在恢复演替的初期阶段,羊草种群在小尺度范围内偏离泊松聚块模型,而在整个取样范围内完全符合嵌套双聚块模型;随着恢复演替时间的推移,在恢复演替的后期,在整个取样尺度上,羊草种群与泊松聚块模型相吻合。这是很有意义的生态学现象。这一实例表明在应用点格局分析种群空间格局时,仅通过完全空间随机模型的检验来分析格局特征,或许很难论证复杂的生态过程,而选择一些完全空间随机模型以外的较复杂的零模型,可能发现一些有价值的生态学现象,对揭示格局掩盖下的内在机制有所裨益。     

GTPase Activity of MxB Contributes to Its Nuclear Location,Interaction with Nucleoporins and Anti-HIV-1 Activity

The human myxovirus resistance 2(Mx2/Mx B) protein, a member of interferon(IFN)-inducible dynamin-like large GTPases, restricts a number of virus infections. Inhibition of these viruses occurs at poorly-defined steps after viral entry and has a common requirement for Mx B oligomerization. However, the GTPase activity is essential for the anti-viral effects of Mx B against herpesviruses and HBV but not HIV-1. To understand the role of Mx B GTPase activity, including GTP binding and GTP hydrolysis, in restriction of HIV-1 infection, we genetically separated these two functions and evaluated their contributions to restriction. We found that both the GTP binding and hydrolysis function of Mx B involved in the restriction of HIV-1 replication. The GTPase activity of Mx B contributed to its nuclear location, interaction with nucleoporins(NUPs) and HIV-1 capsids. Furthermore, Mx B disrupted the association between NUPs and HIV-1 cores dependently upon its GTPase activity. The function of GTPase activity was therefore multi-faceted, led to fundamentally distinct mechanisms employed by wild-type Mx B and GTPase activity defective Mx B mutations to restrict HIV-1 replication.     

Simultaneous expression of glutaryl-7-aminocephalosporanic acid acylase gene and lysis genes of phage λ in a recombinant E. coli

Glutaryl-7-aminocephalosporanic acid acylase (GLA), recommended for use in the form of immobilized-enzyme, is one of the two key enzymes in the two-step synthesis of 7-aminocephalosporanic acid. For simplifying the process of cell disruption and immobilization, the lysis genes of phage λ (S⁻RRz) with the S amber mutation were designed to introduce into the over-expression system of GLA. A novel recombinant strain, E. coli TB1/pMKC-AS, simultaneously containing the maltose binding protein gene (malE), the lysis genes (S⁻RRz) and the target GLA gene (Acy) in a same operon, was successfully constructed. Under neutral pH conditions, cell growth and GLA activity of TB1/pMKC-AS was not affected by the presence of the lysis genes, however, autolysis phenomenon was observed under weak alkaline conditions. Through pH control and fed-batch culture, the GLA activity of TB1/pMKC-AS reached as high as 6810 U/L with 24.8 g/L dry cell density (OD₆₀₀ = 67.9) in a 5 L fermentor. In contrast to the cells of E. coli TB1/pMKC-Acy without the lysis genes, the mild EDTA/Tris buffer (pH 8.0) can cause the lysis of the cells of TB1/pMKC-AS containing the lysis genes. Correspondingly, a mild pH 9.0/42 °C incubation method was developed for conveniently degrading the recombinant cells of TB1/pMKC-AS, based on the expression of the lysis genes. Further experiments showed that the cell lysate after the mild incubation disruption can be directly immobilized by 10% polyacrylamide to make the immobilized enzymes. In comparison with the immobilized GLA from TB1/pMKC-Acy, the immobilized cell lysate of TB1/pMKC-AS has the similar characteristics of catalysis stability, implying a great potential for industrial application of the lysis genes-assisted cell disruption.     

不同型别的基因工程干扰素抗病毒活性的比较

对大肠杆菌生产的不同型别的基因工程干扰素rIFN-α1(α1)、rIFN-αA(αA)、rIFN-β17ser(β17ser)和rIFN-γ(γ),以及自然人白细胞干扰素nIFN-αco,在不同细胞上对不同病毒的抗病毒活性做了比较研究。证明:①α1抗病毒作用的细胞谱较广,尤其在牛肾MDBK细胞和猪肾PK细胞上有很高的活性,分别为在人细胞上的29倍和7倍。β17ser和γ在异种细胞上活性极低,在鼠、猪和牛肾细胞上的活性为人细胞上的1～2％以下。②5种干扰素对麻疹、CoxB1、Sindbis、腺病毒7型和Ⅰ、Ⅱ型单纯疱疹病毒的抗病毒活性无明显差异。但不同病毒对干扰素的敏感性有明显差别,以Sindbis病毒为最敏感,7型腺病毒最不敏感。③5种干扰素对流行性出血热病毒均有明显的抗病毒作用,尤以人α1型和β干扰素作用最强,α1对出血热病毒的抗病毒活性是对滤泡性口膜炎病毒(VSV)的1/2.85,人β干扰素是对VSV的1/4.1。上述结果为人基因工程干扰素的临床应用提供了实验依据。     

ON SOME NEW OSTRACODS FROM KWANGSI

IntroductionThe materials which form the subject of the present paper were collectedfrom the following formations and localities:(1)The Middle Devonian Yukiangformation of Yungchun district and(2)The Devonian lenticular limestone ofLingchuan district of Kwangsi.The ostracods of the second locality are preservedas internal moulds and therefore are far from being complete.