Coordinated mRNA and Protein Expression of Human LAMP-1 in Induction of Melanogenesis After UV-B Exposure and Co-Transfection of Human Tyrosinase and TRP-1 cDNAs

In order to better understand the cascade of melanogenic events in melanocytes, this report has introduced our two recent approaches for the expression of melanogenesis/or melanosome-associated genes and encoded proteins in melanocytes (melanoma cells) after repeated exposure to UV -B and after cotransfection of two human genes, i.e., tyrosinase and tyrosinase-related protein-1 (TRP-1). Repeated exposure of UV B (2.5–5.0 mJ/cm²) caused not only upregulation of tyrosinase and TRP-1 genes but also coordinated increase in the gene and protein synthesis expression of Lamp-1 (lysosome-associated membrane protein-1). When COS-7 kidney cells and amelanotic melanoma (C32 and SKMEL-24) and melanotic melanoma (G361 and SK-MEL-23) cells were exposed to cotransfection of human tyrosinase and TRP-1 cDNAs, there was also an increased expression of Lamp-1 mRNA and protein along with tyrosinase activation and new melanin synthesis. Importantly, single transfectants of human tyrosinase cDNA revealed marked cellular degeneration, whereas this degeneration was not seen in single transfectants of TRP-1 cDNA or cotransfectants of human tyrosinase and TRP-1 cDNAs, indicating that TRP-1 prevented, along with Lamp-1, programmed death of melanocytes after transfection of tyrosinase gene. The coordinated expression of TRP-1 and Lamp-1 was further confirmed by antisense oligodeoxynucleotide hybridization experiment against Lamp-1 gene, showing the decreased expression of TRP-1 as identified by three different types of anti-TRP-1 monoclonal antibodies. We propose therefore that human tyrosinase and TRP-l, when activated or expressed together, will coordinate to upregulate the mRNA expression and protein synthesis of Lamp-1. The Lamp-1 molecules will, in turn, cover the inner surface of melanosomal membrane, together with TRP-1 molecules, thus protecting the melanosomal membrane from toxic melanin intermediates generated during melanogenesis in the presence of active tyrosinase. In contrast, the expression of other lysosome-related proteins, e.g., β-galactosidase and CD63 is not stimulated in new melanogenesis.     

支序分类CLADISTICS在浮游多毛类眼蚕科ALCIOPIDAE系统演化研究中的应用

本论文运用支序分类学,借助于计算机技术,详细探讨了浮游多毛类眼蚕科(Alciopidae)九属的系统演化关系,并同前人的进化分类学和数值分类学研究结果进行了比较,对眼蚕科各属的演化途径提出了新的见解。     

柑橘大实蝇精巢、精泵和精泵内骨骼的生长发育状况

【目的】柑橘大实蝇是一种严重为害柑橘类果实的经济害虫。研究其精巢、精泵以及精泵内骨骼生长发育状况,有助于提高柑橘大实蝇人工繁殖效率以及其田间防治效果,为柑橘大实蝇的预测预报及防治提供理论基础。【方法】基于光学显微镜测量恒温和室温条件下柑橘大实蝇雄虫的精巢、精泵以及精泵内骨骼的长度和宽度,并建立其长度、宽度和指数的函数模型,比较恒温和室温2种饲养条件下其雄虫器官发育状况差异。【结果】无论是在恒温还是室温条件下饲养,随着柑橘大实蝇雄成虫日龄的增加,其精巢、精泵以及精泵内骨骼的长度、宽度和指数变化趋势均符合幂函数增长模型。在恒温和室温条件下,其雄虫的精巢宽度、精泵的长度和宽度以及指数、精泵内骨骼宽度均无明显差异。在室温条件下饲养的雄虫的精巢长度[(4.00±0.14) mm]及指数(3.40±0.14)、精泵内骨骼长度[(1.65±0.03) mm]及指数(1.84±0.08)均分别显著高于在恒温条件下饲养的雄虫的精巢长度[(3.75±0.13) mm]及指数(3.19±0.14)、精泵内骨骼长度[(1.61±0.03) mm]及指数(1.77±0.08)。【结论】变温(室温)比恒温更有利于柑橘大实蝇雄虫的精巢和精泵内骨骼的发育,并推荐使用精泵长度推断其雄虫日龄的方法。     

含吸氢酶基因（hup）嵌合质粒的构建和吸氢酶活性在阴沟肠杆菌中的表达

以质粒ｐＲＫ４０４为载体亚克隆含大豆根瘤菌吸氢酶结构基因（ｈｕｐ）的片段,构建成嵌合质粒ｐＨＲ１１、ｐＨＲ４和ｐＨＲ１０。通过三亲本杂交将这些嵌合质粒导入无吸氢活性的Ｒｈｏｄｏｂａｃｔｅｒｓｐｈａｅｒｏｉｄｅｓ２４１菌株（Ｈｕｐ－）,均获得Ｈｕｐ＋的接合子。利用启动子检测质粒ｐＭＰ２２０证明,在ｈｕｐ对结构基因上游１．２ｋｂ内存在ｈｕｐ启动基因片段。以ｐＲＫ２０１３为助质粒可将ｐＨＲ１１导入Ｅｎｔｅｒｏｂａｃｔｅｒｃｌｏａｃａｅ和Ｋｌｅｂｓｉｅｌｌａｏｘｙｔｏｃａ等土壤固氮菌株。本文以接合子Ｅ．ｃｌｏａｃａｅＥＨ１１１３为例,通过对基因组ＤＮＡＳｏｕｔｈｅｒｎ杂交分析证明,嵌合质粒ｐＨＲ１１在ＥＨ１１１３中稳定贮存和复制。Ｈ２诱导接合子ＥＨ１１１３吸氢酶活性高表达,吸氢活性与放氢活性比值约为对照的两倍。当以延胡索酸为电子受体时,吸氢酶的吸氢作用支持菌株固氮酶活性的提高。     

大肠杆菌rpoH基因的克隆,表达及其产物的纯化

本文用ＰＣＲ方法获得大肠杆菌热休克蛋白转录因子σ３２的编码基因ｒｐｏＨ,并克隆在含有ｔａｃ启动子的表达载体ｐＵＨＥ中,经ＩＰＴＧ诱导,在大肠杆菌中表达了Ｃ端融合有６个寡聚组氨酸的σ３２。表达产物经金属螯合层析一步纯化,达到ＳＤＳ－ＰＡＧＥ银染一条带纯度,氨基酸组成分析及Ｎ端序列分析结果与文献报道一致。３５Ｓ细胞内参入实验表明：即使在较低的温度下,表达产物σ３２（Ｈｉｓ）６也能导致热休克蛋白如ＧｒｏＥｌ、ＤｎａＫ、Ｈｔｐ的大量合成．     

油菜主序优势及其利用初析

油菜具有主序优势,主要表现在结角数上,在角粒数、千粒重及品质上也很显著。不同类型其优势强弱不同,白菜型和甘蓝型优势明显,芥菜型几乎不具有优势。在甘蓝型油菜中因品种、密度不同优势差异显著。增加密度可使主序在产量中的比例增加,在５万株／亩时可达７３．０５％．主序具有结角率高、成熟早等优点,通过选育优势强的品种,适当增加密度,合理调整布局,有望使油菜产量有较大幅度地提高     

O139霍乱弧菌检测方法的研究─诊断血清的制备

本文以Ｏ１３９死菌免疫健康家兔,经吸收去除非特异性凝集素制成的特异性诊断血清,专供诊断霍乱弧菌Ｏ１３９之用。采用玻片凝集试验对５株Ｏ１３９菌株及１２６株肠道菌进行验证,在敏感性和特异性方面均获得满意的结果。     

草鱼垂体生长激素分离纯化及其抗体制备的研究

应用碱性抽提,亲和层析,凝胶过滤和离子交换层析等技术从草鱼垂体中分离提纯出纯度高的草鱼生长激素（ｇｃＧＨ）用酶联免疫吸附测定法（ＥＬＩＳＡ）检测表明草鱼ＧＨ与大马哈鱼ＧＨ抗血清具有明显的免疫交叉反应,而与大马哈鱼催乳素（ＰＲＬ）抗血清没有交叉反应,聚丙烯酰胺凝胶电泳表明草鱼ＧＨ为单一蛋白带,其分子量约为２２５００道尔顿,等电聚焦揭示出草鱼ＧＨ主要由等电点为４．７和５．０的两条蛋白带组成,用纯化的草     

Synergistic effects of TAL1 over-expression and PHO13 deletion on the weak acid inhibition of xylose fermentation by industrial Saccharomyces cerevisiae strain

In the industrial production of bioethanol from lignocellulosic biomass, a strain of Saccharomyces cerevisiae that can ferment xylose in the presence of inhibitors is of utmost importance. The recombinant, industrial-flocculating S. cerevisiae strain NAPX37, which can ferment xylose, was used as the parent to delete the gene encoding p-nitrophenylphosphatase (PHO13) and overexpress the gene encoding transaldolase (TAL1) to evaluate the synergistic effects of these two genes on xylose fermentation in the presence of weak acid inhibitors, including formic, acetic, or levulinic acids. TAL1 over-expression or PHO13 deletion improved xylose fermentation as well as the tolerance of NAPX37 to all three weak acids. The simultaneous deletion of PHO13 and the over-expression of TAL1 had synergistic effects and improved ethanol production and reduction of xylitol accumulation in the absence and presence of weak acid inhibitors.