IFN-γ诱导过氧化酶抗病原体增殖的研究进展

IFN-γ是一种多效能的细胞因子 ,具有抗病毒、非病毒性病原体 ,抑制肿瘤细胞增殖和调节免疫反应等功能。IFN-γ可诱导细胞合成多种蛋白质和酶 ,其中某些产物被认为与其抗感染活性有关 ,如一氧化氮合酶 (NOS)、吲哚胺 2 ,3过氧化酶 (IDO)等。IDO是催化色氨酸降解的酶 ,而色氨酸是人体的一种必需氨基酸 ,是合成蛋白质不可缺少的原料 ,也是重要的神经递质5 -羟色胺的前体物质。色氨酸缺乏 ,细胞生长会受到影响。越来越多的证据显示 ,IDO降解色氨酸与 IFN- γ介导的限制细胞内外病原体生长 ,抑制肿瘤细胞增殖有关 ,本文就这方面的研究…     

用焦锑酸钾技术研究玉米叶片中的钙

应用改良的焦锑酸钾沉淀技术,研究了玉米叶绿体钙的亚细胞定位和缺钙对玉米叶片细胞结构的影响,结果表明,在玉米两种叶绿体的被膜、片层结构和基质中均有锑酸钙沉淀存在,其中的基粒类囊体和基质类囊体具有较高的钙水平.研究结果还表明,缺钙会引起玉米叶片维管束鞘细胞、筛管分子、伴胞和叶肉细胞内与膜结合的钙离子释放出来,呈不规则的锑酸钙沉淀散布在细胞内,同时使细胞的内膜结构(如内质网、液泡等)遭到破坏而解体,随着缺钙程度的加深,叶绿体的片层结构开始解体.这说明钙对叶绿体的功能和维持细胞膜结构的完整性起着重要的作用.     

灵芝有效化学成分研究进展

灵芝有效化学成分包括多糖、三萜类化合物、肽和氨基酸、蛋白质、腺苷、有机酸、生物碱等.从提取分离方法、结构鉴定、生物活性等方面进行了概述.     

豆腐渣的新用途

<正> 豆腐渣内含有一定数量的蛋白质。这种蛋白质含有色氨酸、蛋氨酸等多种氨基酸,不含胆固醇,是     

大棚蔬菜缺钙症及其防治

蔬菜作物大多喜钙,对钙的需要量较多.我国北方石灰性土壤分布很广,其含钙丰富,一般不缺钙,但是,近年来大棚蔬菜的缺钙症日趋增多,严重的影响了蔬菜的品质、质量和经济效益.     

海刺猬和中间球海胆性腺的组织学和组织化学

对海刺猬Glyptocidaris crerularis和中间球海胆Stronylocentrotus intermedius性腺的组织学和组织化学进行了比较研究。结果表明,两者性腺结构均为滤泡型,滤泡由生殖细胞和营养细胞组成,随着生殖细胞的发育成熟,营养细胞中颗粒逐渐减少,当生殖细胞排放后,营养颗粒的数量逐渐增加,且中间球海胆的营养颗粒数量较海刺猬多。观察和分析了海刺猬和中间球海胆的雌、雄生殖细胞、营养颗粒、滤泡细胞的DNA、RNA、多糖、蛋白质和结合脂类的分布、数量及其变化,发现中间球海胆滤泡中营养颗粒的多糖和蛋白质含量比海刺猬高,其它指标两者都很相近。     

多年生藤本豆多糖、蛋白质对小白鼠免疫功能的调节作用研究

目的:研究多年生藤本豆多糖、蛋白质对小白鼠免疫功能生理调节作用。方法:测定多年生藤本豆多糖、蛋白质对小鼠脾指数、胸腺指数、淋巴细胞增殖的情况。结果:多年生藤本豆多糖、蛋白质明显促进小鼠B淋巴细胞和T淋巴细胞的增殖,增强小白鼠巨噬细胞的吞噬活力和溶血素抗体生成。结论:多年生藤本豆多糖、蛋白质对小白鼠具有提高机体免疫防御能力。     

甜玉米的栽培技术

甜玉米既是一种风味食品,也是一种营养保健品,其籽粒含糖量高,糖、蛋白质含量都在13%以上.其蛋白质中富含人体所必需的赖氨酸、色氨酸,在18种氨基酸中,甜玉米含有人体所必需的8种氨基酸比普通玉米高1倍以上.甜玉米的籽粒可加工成罐头或速冻果穗,也可以生产饮料,同时,采收果穗后的茎叶也是发展畜牧业的好饲料,因此,甜玉米的综合利用前景十分广阔.     

中国对虾蛋白质的营养价值评价

为系统了解中国对虾蛋白质的营养价值,通过分析其基本营养成分含量及蛋白质的氨基酸组成,分别采用蛋白质氨基酸评分法、必需氨基酸化学评分法以及必需氨基酸指数法对其蛋白质的营养价值进行了评价.结果表明:中国对虾肉和对虾头的蛋白质含量丰富;组成中国对虾肉蛋白质的氨基酸(色氨酸除外)总量(以干重计,下同)为73.16 g/100 g,其中必需氨基酸总量为25.12 g/100 g,没有限制性氨基酸;组成对虾头蛋白质的氨基酸(色氨酸除外)总量为49.47 g/100 g,其中必需氨基酸总量为16.41 g/100 g,苯丙氨酸和酪氨酸为其限制性氨基酸.组成中国对虾肉和虾头蛋白质必需氨基酸化学评分最高的均是赖氨酸.中国对虾肉和虾头蛋白质的必需氨基酸指数分别为72.98%和68.37%.中国对虾蛋白质氨基酸组成平衡、合理,是高质量的蛋白质.     

龙眼果实挂树成熟与退糖期间的解剖学结构比较

以石硖和储良两个品种龙眼(Dimocarps longana Lour. cv. Shixia and Chuliang)果实为试材,比较了挂树成熟与衰老(退糖)期间果皮和果肉的解剖学结构,测定了成熟与衰老期间果肉可溶性固形物(TSS)含量。结果表明:石硖成熟期比储良短,分别为14 d和21 d,之后退糖,TSS含量的下降速率分别为每天0.60%和0.31%。完全成熟时,龙眼果皮组织结构较为完整,外果皮为数层平行排列的变形细胞,附着不连续的角质层和蜡块;中果皮为大的层状薄壁细胞,间以块状栓质组织、石细胞和维管束;内果皮为1~2层紧密排列的薄壁细胞,胞壁角质层深厚;果肉表面光滑,薄壁细胞结构清晰完整、排列整齐。退糖时,外表皮的蜡质层和表皮毛脱落,外、中果皮里的胞间隙或层状缝隙增大,内果皮表面出现破损和"钉"状突起物;果肉表面皱褶增多,结构塌陷,胞壁可能增厚。不同龙眼品种之间的果皮结构差异主要在于成熟时的中果皮,石硖细胞排列紧密、缝隙小而少,而储良细胞间隙较大;果肉结构差异在于成熟时石硖胞壁坚挺、呈长圆形,而储良胞壁卷曲、呈狭长型,刚性弱于石硖;退糖时储良果肉皱缩塌陷比石硖明显,但后者出现细胞壁纤维化增厚的特异现象。     

A proteomic approach to investigating the promotive effects of brassinolide on root growth of rice seedlings

Brassinolide influenced rice (Oryza sativa L.) root growth in a concentration-dependent manner. Roots grown in 0.1 nmol/L BL were 28% longer than those in the control. On the other hand, the roots grown in 1000 nmol/L BL were 65% shorter in comparison with those in the control. To investigate how BL influences rice root growth, proteome analysis techniques were applied. After BL treatments, total proteins from rice root were extracted separately. Extracted proteins were separated by two-dimensional polyacrylamide gel electrophoresis and analyzed using an automated protein sequencer and mass spectrometer. There were 33 proteins that showed differences in the accumulation levels as a result of treatments with BL. Proteins related to stress tolerance, enzymes, and cell structure were mainly found in the root. There were many proteins regulated by other hormone or light also. Results suggest that the physiologic functions of these proteins detected using powerful proteome analysis are implicated in root elongation triggered by BL. High-level brassinosteriod (BR) indicated that IAA amidohydrolase, which can release active IAA from IAA pool was increased, and the IAA level was so high that the root length was inhibited.     

杜仲ABC转运蛋白基因家族成员鉴定与分析

ABC转运蛋白(ATP—binding cassette transpoter)是一类庞大而古老的跨膜运输蛋白家族,在生物体内参与多种物质的转运积累、有害物质解毒、气孔调节、植物防御等生理活动。杜仲(Eucommia ulmoides Oliv)作为重要的中药材,其药用成分主要为次生代谢产物,次生代谢物转运与积累过程需要ABC转运蛋白的参与。利用生物信息学手段对杜仲ABC转运蛋白基因家族进行鉴定,并分析该家族蛋白质性质和结构、跨膜结构、亚细胞定位、系统进化关系。研究表明,EuABC家族生物信息学预测有76个成员,含有1~7个保守基序;编码蛋白多为稳定蛋白,主要分布于细胞质膜上,二级结构以α-螺旋和无规卷曲为主要构成元件;进化树分析表明,杜仲ABC转运蛋白家族可分为8个亚家族(A~G;I),每组成员数量分别为3、19、14、1、1、1、29、8。研究结果可为进一步研究杜仲次生代谢物质转运与积累奠定基础,也为其他植物ABC转运蛋白家族的研究提供了参考依据。     

植物诱导抗病机理的研究进展

从诱导植株相关酶活性变化、细胞壁的保护反应,植物抗毒素的积累以及新蛋白的合成四个方面综述了植物诱导抗病机理的研究进展。     

Unravelling transcriptome changes between two distinct maize inbred lines using RNA-seq

Seed size play a significant role in maize yield production. Two maize inbred lines with distinct seed size and weight, V671 (a large-seed inbred line) and Mc (a small-seed inbred line), were investigated by RNA-seq at 14 days after pollination (DAP), when maize endosperm undergoes an active transition from mitosis to storage accumulation. RNA-seq expression data showed that the small-seed line Mc had a higher storage accumulation activity, whereas the large-seed kernel line V671 possessed a higher DNA synthesis activity. An investigation of the pattern of increasing kernel width at serial DAPs showed that V671 experienced an increased kernel width later than did Mc, but the rate and duration of increase were longer in V671. SDS-PAGE of the storage proteins and quantitative RT-PCR of cell cycle-related genes and indole-3-acetic (IAA) synthesis genes certified that the transition from mitosis to storage accumulation starts earlier in Mc. We hypothesized that the difference in the mitosis-to-storage accumulation transition accounts for the larger seed size in V671 vs. Mc.     

Accumulation of Protein Fractions during Grain Filling of Wheat Genotypes Differing in Protein Content and Baking Quality

The accumulation of protein fractions was analyzed on developing and mature wheat grains of three cultivars differing in protein content and baking quality. There was a slight difference in the accumulation of cytoplasmic proteins in the cultivars used. The high yield but low protein cultivar showed a consistent decline of protein content during grain filling but the high - protein cultivars increased their psotein contant after 25 days post-anthcsis. The accumulation of storage proteins was different from that of cytoplasmic protein, and there were also cultivar variations. However, all cultivars reached their, maximum-synthesizing capacity for storage proteins at maturity. The relationship between the protein fractions or their ratio and baking quality was also discussed.     

枣果实不同发育阶段蛋白质组动态研究

枣果实在发育和成熟过程中涉及多种复杂的生理生化变化。为了解枣果实在发育过程中蛋白质组的变化情况,利用液质联用(LC-MS)技术对主栽制干枣品种——骏枣幼果期、膨大期、白熟期、初红期和全红期5个阶段的果实进行了非标记定量蛋白质组动态变化研究。结果表明,各时期果实与其前一阶段相比分别有差异表达蛋白189、356、82、69个。基因本体(GO)注释结果显示:幼果与膨大果的差异蛋白主要富集在核酸代谢过程,膨大期果实与白熟果的差异蛋白主要富集在碳水化合物代谢过程。从5个阶段的果实中分别鉴定到604、186、91、83、189个特异表达蛋白。Mercator注释和KEGG通路注释结果显示,幼果期特异表达蛋白主要参与了RNA转运通路。加权基因共表达网络(WGCNA)分析显示,幼果期高表达蛋白主要与核糖体合成相关。总之,枣果实在白熟期以前与细胞分裂和膨大相关的蛋白表达量和富集程度高,从白熟期开始与碳水化合物积累相关的蛋白质表达上调。本研究从蛋白质组学水平阐明了枣果实发育成熟过程中蛋白质组分的动态变化,为提高枣果实品质奠定了理论基础。     

Identification of monocyte chemotactic activity produced by malignant cells

Human malignant cells secrete low molecular size proteins that attract peripheral blood monocytes and may be responsible for the accumulation of tumor-associated macrophages observed in vivo. Similar chemotactic proteins are secreted by cultured vascular smooth muscle cells. The predominant monocyte chemoattractants produced by tumor cells of differing origin were demonstrated to be related to smooth muscle cell-derived chemotactic factor. Thus, a single class of chemotactic proteins is produced by different cell types, which suggests a common mechanism for the recruitment of monocytes and macrophages. These results are significant in view of the potential of macrophages to affect tumor growth.     

博落回对铅的耐性、富集及生理响应研究

以草本植物博落回（Macleaya cordata）为供试植物,采用沙培盆栽实验研究其对重金属铅（Pb）的耐性、富集及生理响应机制。结果表明：博落回能耐受500 mg/L的Pb胁迫而其生长发育不受影响,高于此浓度时植株生长发育受到抑制。不同组织对Pb的富集能力表现为根>茎>叶,博落回对Pb的富集与转运能力皆随Pb胁迫浓度的升高而减弱。Pb胁迫引起丙二醛（Malondialdehyde, MDA）在植物体内累积。低于500 mg/L的Pb促进叶绿素、可溶性蛋白的合成和抗氧化酶活性的提高,高于此浓度时,则表现为抑制,且导致膜脂过氧化与生物膜的损伤。Pb主要以迁移活性低的化学形态存在于细胞壁和可溶性组分中,浓度升高会导致Pb向迁移毒性强的形态转化。透射电子显微镜（TEM）观察到高浓度的Pb胁迫会损害细胞壁结构,使Pb进入细胞内部,对细胞造成毒害。傅里叶红外光谱仪（FTIR）分析表明,Pb胁迫会提高细胞内-OH、-COOH等基团和有机酸、蛋白质的含量,在低浓度时可与Pb结合,削弱其对博落回的毒性。     

Toxic proteins in neurodegenerative disease

A broad range of neurodegenerative disorders is characterized by neuronal damage that may be caused by toxic, aggregation-prone proteins. As genes are identified for these disorders and cell culture and animal models are developed, it has become clear that a major effect of mutations in these genes is the abnormal processing and accumulation of misfolded protein in neuronal inclusions and plaques. Increased understanding of the cellular mechanisms for disposal of abnormal proteins and of the effects of toxic protein accumulation on neuronal survival may allow the development of rational, effective treatment for these disorders.     

杜仲胶在杜仲叶发育过程中的含量变化研究

综合应用石蜡切片法和实验室提胶法研究了杜仲胶在杜仲叶生长发育过程中的变化规律,探讨了杜仲叶结构发育与杜仲胶积累的关系.结果表明,杜仲叶含胶细胞在一年中的形成积累具有一定的独立性.从叶片展开到叶片停止生长仅有1个月时间,叶片大小在生长30 d以后基本保持恒定.随着叶片栅栏组织、海绵组织等叶肉细胞的分化发育,叶片内含胶细胞也在不断地形成积累;叶片各结构生长停止后,含胶细胞仍继续增加和生长,叶片含胶率总体上呈增加的趋势.由于杜仲叶片内杜仲胶分泌、积累与叶片生命周期在1年中同步,使在将近黄落的11月份叶片含胶率较高,可达1.11％.