最新病毒研究国外信息(1-3)

根据NS1蛋白是一种多功能促进病毒复制的组分,并有拮抗干扰素的作用,应用基于酵母的测定方法,筛选获得了抑制NS1功能的化合物。这一化合物有反转抑制干扰素mRNA的功能,不仅可作为药物开发,还可用于探讨NS1生物功能（J Virol,2009,83（4）：1881—1891）。     

RNA Modified Uridines VI: Conformations of 3-[3-(S)-Amino-3-Carboxypropyl]Uridine (acp3U) from tRNA and 1-Methyl-3-[3-(S)-Amino-3-Carboxypropyl]Pseudouridine (m1acp3Ψ) from rRNA

Abstract

The conformation of chemically synthesized acp³U is 60& 3′-endo, gauche⁺, whereas that of m¹acp³Ψ is 60& 2′-endo, gauche⁺. We conclude that the difference in conformation probably imparts important local structures to their respective tRNA and rRNA.     

甲1(H1N1)和甲3(H3N2)型流感病毒在小鼠体内诱导细胞免疫反应的研究

比较了甲型流感病毒A/HK/123/77(H1N1)和A/Qld/6/72(H3N2)及其具有相应表面抗原的两个冷适应基因重分配株(Cold-Adapted Reassortant)的子代毒株CR35和CR6,在小鼠体内诱导初次细胞毒性T细胞(简称Tc)反应的能力。静脉注射相同剂量病毒后第6天,甲3型A/QLd和CR6所诱导的脾细胞Tc活性均比甲1型A/HK和CR35者高100倍。编码内部蛋白的基因相同而表面抗原的基因不同的CR6与CR35所诱导的Tc活性也不同,说明了表面抗原决定着初次Tc反应的强度。用无关的流感病毒A/SW/72(H6N5)攻击已用低剂量(10~4EID_(?))病毒致敏的小鼠表明,对A/Qld和CR6致敏者所诱导的第二次Tc活性,比A/HK和CR3S致敏者的稍高;但对用大剂量病毒致敏者,则均能产生同样好的第二次Tc活性。对Tc识别感染靶细胞上的病毒成份进行了讨论。     

模型系统(HONH_3HOH)~(-1)中的质子传递研究

本文提出了一个包含两个氢键涉及单质子和双质子传递的简化模型系统(HONH_3HOH)~(-1),并用MINDO/3方法研究了质子传递过程,得到了有关两质子传递的势能面,其每一步都选择性地进行了几何优化.单质子传递的两个势阱是不对称的,它的位垒随着氢键变长而急剧增高.α质子的转移导致体系电荷的不均匀堆积,因此其位阻较大,通过β质子传递可大大降低它的位垒,在这种意义上双质子传递比单质子传递更可能.最后讨论了它和丝氨酸蛋白酶体系催化机理的关系.     

问题解答(1)

问:绿色植物在有阳光时行光合作用吸二氧化碳放出氧气,在晚上没阳光时只有呼吸作用吸氧气放二氧化碳,为什么总说早晨到树林中散步空气好呢? 答:因为空气流动得很厉害,所以在一般树林中白天夜晚O_2及CO_2含量的改变是极小的.说早晨空气好,并不是植物起了什么作用,而是因为夜间人们的活动停止了,车马不在路上奔驰了,工厂的烟囱不冒烟了.加上树林中的湿度较大,尘土都降落在地上,空气就更为清洁了.我们夜间睡在屋中,屋中温度较高,不好气味的有机物(器物中发出或人呼出)空气中也很多,所以一到树林中,凉爽而清洁的空气,眼界的开朗就使我们心神为之一振.(吴相钰、董愚得答)     

TGFβ-activated kinase 1 (TAK1)-binding proteins (TAB) 2 and 3 negatively regulate autophagy

Transforming growth factor β-activated protein kinase 1 (TAK1)-binding protein 2 (TAB2) and its close homolog TAB3 are initially characterized as adapter proteins essential for TAK1 activation in response to interleukin-1β and tumour necrosis factor-α. However, the physiological roles of TAB2 and TAB3 are still not fully understood. Here we report that TAB2 and TAB3 bind to Beclin1 and colocalize in the cytoplasm. TAB2 also interacts with ATG13 and is phosphorylated by ULK1. Overexpression of TAB2 or TAB3 induces punctate localization of ATG5 under the normal culture condition. Knockdown of TAB2 and TAB3 results in the decrease in endogenous protein level of p62/SQSTM1 under the normal culture condition, while overexpression of TAB2 results in the accumulation of p62/SQSTM1 independently of TAK1. The decrease of p62/SQSTM1 induced by the knockdown of TAB2 and TAB3 is largely dependent on ATG5. These results suggest that TAB2 and TAB3 negatively regulate autophagy independently of TAK1 activity.     

1-Bromo-3-(1',1'-dimethylalkyl)-1-deoxy-Δ(8)-tetrahydrocannabinols: New selective ligands for the cannabinoid CB(2) receptor

Δ(8)-Tetrahydrocannabinol (26), 3-(1',1'-dimethylbutyl)- (12), 3-(1',1'-dimethylpentyl)- (13), 3-(1',1'-dimethylhexyl)- (14) and 3-(1',1'-dimethylheptyl)-Δ(8)-tetrahydrocannabinol (15) have been converted into the corresponding 1-bromo-1-deoxy-Δ(8)-tetrahydrocannabinols (25, 8-11). This was accomplished using a protocol developed in our laboratory in which the trifluoromethanesulfonate of a phenol undergoes palladium mediated coupling with pinacolborane. Reaction of this dioxaborolane with aqueous-methanolic copper(II) bromide provides the aryl bromide. The affinities of these bromo cannabinoids for the cannabinoid CB(1) and CB(2) receptors were determined. All of these compounds showed selectivity for the CB(2) receptor and one of them, 1-bromo-1-deoxy-3-(1',1'-dimethylhexyl)-Δ(8)-tetrahydrocannabinol (10), exhibits 52-fold selectivity for this receptor with good (28nM) affinity.     

Linkage of acid α-glucosidase (Gaa) and Thymidine kinase (Tk-1) to Esterase-3 (Es-3) on mouse Chromosome 11

Inheritance in recombinant inbred (RI) strains of restriction fragment length variants (RFLVs) detected by probes specific for Gaa and Tk-1 showed tight linkage of both to Es-3 on mouse Chromosome (Chr) 11. This result extends the region of homology between mouse Chr 11 and human chr 17q.     

(1–3)-β-Glucan synthesis ofNeurospora crassa

(1–3)--d-Glucan synthase activity ofNeurospora crassa was localized to the plasma membrane by autoradiography of colloidal gold-labeled plasma membranes. The active site of glucan synthase for substrate hydrolysis was determined to be cytoplasmic facing. However, glucan synthase activity present in intact protoplasts was partially sensitive to Novozym 234 and to glutaraldehyde treatments, suggestive that enzyme activity is transmembrane. Enzyme activity also directed the formation of microfibrils in vitro. Taken together, these and previous results support the following scheme for glucan synthesis: 1. The sequential addition of glucose residues from UDP-glucose to glucan chains occurs on the cytoplasmically facing portion of glucan synthase. 2. As each glucan chain is synthesized, it is extruded to the extracytoplasmic side of the plasma membrane. 3. As each chain is extruded, it forms interchain hydrogen bonds with adjacent chains, resulting in glucan microfibril assembly.     

Untersuchungen zum C′3-Polymorphismus (β 1c-Globulin)

Zusammenfassung Serumproben von 1322 Blutspendern aus Hessen, 40 Familien mit 89 Kindern, 20 Mutter-Kind-Kombinationen und 268 Sera einer Bantupopulation aus Portugiesisch Angola wurden mit einer modifizierten Technik der Hochspannungs-Dünnschichtelektrophorese auf Agarosegel hinsichtlich des C3-Polymorphismus untersucht. Die Genfrequenzen für Weiße (C3^S=0.779, C3^F=0.215) und Neger (C3^S=0.95, C3^F=0,048) stimmen gut mit den Werten anderer Autoren überein. Insgesamt ließen sich bei Weißen 9 Phänotypen sicher abgrenzen, bei Negern 3. Familienstudien bestätigten den für die Allele C3^S und C3^F angenommenen Vererbungsmodus (autosomal codominant) ausnahmslos. Die Frage der Lagerungsstabilität des C3 wurde abschließend untersucht.

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Investigations on C3-polymorphism ( _1c-Globulin)Gene frequencies and family studies in blood donors from Hessen and a Bantu population

Summary Serum samples of 1322 unrelated individuals from Hessen (Germany), 40 families with 89 children, 20 mother-child-combinations and 268 sera of a Bantu population from Angola were examined for C3 polymorphism using a modified technique of high voltage agarose gel electrophoresis. The gene frequencies for Caucasians (C3^S=0.779, C3^F=0.215) and negroes (C3^S=0.95, C^F=0.048) are in good accordance with those obtained by other authors. In total 9 different phenotypes were observed in Caucasians, 3 phenotypes in negroes. Family studies verify the supposed way of inheritance (autosomal codominant for C3^S and C3^F) without exception. Finally the problem of C3-inactivation by storage was investigated.