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1.
Suzanne Camus Sergio Menéndez Kenneth Fernandes Nelly Kua Geng Liu Dimitris P. Xirodimas David P. Lane Jean-Christophe Bourdon 《Cell cycle (Georgetown, Tex.)》2012,11(8):1646-1655
The discovery that the single p53 gene encodes several different p53 protein isoforms has initiated a flurry of research into the function and regulation of these novel p53 proteins. Full-length p53 protein level is primarily regulated by the E3-ligase Mdm2, which promotes p53 ubiquitination and degradation. Here, we report that all of the novel p53 isoforms are ubiquitinated and degraded to varying degrees in an Mdm2-dependent and -independent manner, and that high-risk human papillomavirus can degrade some but not all of the novel isoforms, demonstrating that full-length p53 and the p53 isoforms are differentially regulated. In addition, we provide the first evidence that Mdm2 promotes the NEDDylation of p53β. Altogether, our data indicates that Mdm2 can distinguish between the p53 isoforms and modify them differently. 相似文献
2.
Jian‐Yong Guo Yong‐Sheng Wang Tian Chen Xiao‐Xu Jiang Ping Wu Tao Geng Zhong‐Hua Pan Meng‐Ke Shang Cheng‐Xiang Hou Kun Gao Xi‐Jie Guo 《Insect Science》2020,27(3):449-462
Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) is a major pathogen of the economic insect silkworm, Bombyx mori. Virus‐encoded microRNAs (miRNAs) have been proven to play important roles in host–pathogen interactions. In this study we identified a BmCPV‐derived miRNA‐like 21 nt small RNA, BmCPV‐miR‐1, from the small RNA deep sequencing of BmCPV‐infected silkworm larvae by stem‐loop quantitative real‐time PCR (qPCR) and investigated its functions with qPCR and lentiviral expression systems. Bombyx mori inhibitor of apoptosis protein (BmIAP) gene was predicted by both target prediction software miRanda and Targetscan to be one of its target genes with a binding site for BmCPV‐miR‐1 at the 5′ untranslated region. It was found that the expression of BmCPV‐miR‐1 and its target gene BmIAP were both up‐regulated in BmCPV‐infected larvae. At the same time, it was confirmed that BmCPV‐miR‐1 could up‐regulate the expression of BmIAP gene in HEK293T cells with lentiviral expression systems and in BmN cells by transfecting mimics. Furthermore, BmCPV‐miR‐1 mimics could up‐regulate the expression level of BmIAP gene in midgut and fat body in the silkworm. In the midgut of BmCPV‐infected larvae, BmCPV‐miR‐1 mimics could be further up‐regulated and inhibitors could lower the virus‐mediated expression of BmIAP gene. With the viral genomic RNA segments S1 and S10 as indicators, BmCPV‐miR‐1 mimics could up‐regulate and inhibitors down‐regulate their replication in the infected silkworm. These results implied that BmCPV‐miR‐1 could inhibit cell apoptosis in the infected silkworm through up‐regulating BmIAP expression, providing the virus with a better cell circumstance for its replication. 相似文献
3.
Wenjun Geng Jinggong Xiangyu Xiuzhen Li Zhongning Zhang Deyuan Han Yongwei Li 《Insect Science》1997,4(4):364-368
Abstract Field trials by sex pheromone of aphid to trap peach aphids Myzus persicae have been carried out in 1995 and in 1996. Suitable time and the effect of ratio of two components nepetalactone and nepetalactol to apply the lure have been observed. 相似文献
4.
耿宝印 《Acta Botanica Sinica》1989,31(7):554-560
十年前在云南省早泥盆世的地层中发现了轮生钩藻(Uncataella verticillata),限于当时的材料,其分类位置未定。本研究所用材料采自它的模式标本产地,化石植物保存良好,首次发现了着生在植物体上的雌性生殖器官——藏卵器。根据藏卵器和植物体其它部分显示的形态特征,本文修订了它的原始描述并对其系统位置进行了探讨,认为轮生钩藻是一种原始的轮藻植物,很可能属于直立轮藻目直立轮藻科中的一个成员。 相似文献
5.
中国大痣小蜂属食植群记述(膜翅目:长尾小蜂科) 总被引:7,自引:1,他引:6
本文报导中国大痣小蜂属Megastigmus食植群Phytophagous group 12种,其中包括5新种:黄杉大痣小蜂Megastigmus pseudotsugaphilus sp.nov.(寄生华东黄杉Pseudotsugagassenii),拟海棠大痣小蜂Megastigmus pseudomali sp.n.(寄主不明),基室大痣小蜂Megastigmus cellus sp.nov 相似文献
6.
Effects of aluminium on growth and cation uptake in seedlings of Eucalyptus mannifera and Pinus radiata 总被引:1,自引:0,他引:1
This experiment was designed to examine the effects of aluminium (Al) on the growth of Pinus radiata (D. Don) and Eucalyptus mannifera subsp. mannifera (Mudie) seedlings in culture solutions in a glasshouse to help explain the failure of radiata pine trees on some acid, low
fertility soils in Australia on which the native eucalypts flourish. Aluminium (Al) in culture solution increased the growth
of roots and shoots of seedlings of both species but while growth of the eucalypt continued to increase with increases in
Al to 2.222 μM, growth of the pine was largest at 370 μM Al. In addition to total root length, specific root length (length per unit dry weight), a measure of fineness of the root,
increased in the eucalypt seedlings as the substrate Al increased. Growth of the shoots and roots of the pine in the absence
of any added Al was extremely poor suggesting that Al, in low concentrations, may be an essential element or ameliorate some
other factors in solution culture at low pH.
Root and shoot concentrations of K increased with increasing Al, whilst Ca and Mg Concentrations decreased and Mn concentrations
were unaffected in both species. Tissue Ca and Mg concentrations were 2 to 3 times higher in the eucalypt seedlings than the
pine at all levels of added Al due to greater uptake of these elements by the eucalypt. In contrast, at the highest concentration
of Al in the medium, shoot Al concentrations were lower in the cucalypt than in the pine due to a greater proportion of Al
being retained in the eucalypt roots.
These differences between the seedlings in terms of root growth and tissue cation concentrations may help explain the ability
of eucalypt species to maintain vigorous growth on acid soils high in Al and low in Ca and P, where growth of the pines failed. 相似文献
7.
Renee Ford Geng Wang Parissa Jannati Douglas Adler Peter Racanelli Paul J. Higgins Lisa Staiano-Coico 《Experimental cell research》1993,206(2)
Expression of SPARC (secreted protein acidic and rich in cysteine), a 43-kDa extracellular matrix-associated glycoprotein involved in tissue remodeling, was quantitated during normal human keratinocyte (NHK) growth in culture and as a function of sodium n-butyrate (NaB)-induced differentiation to mature enucleate cornified envelopes (CEs). Low levels of SPARC expression were observed in the basal-like cells of control NHKs, with isolated cells showing intense SPARC expression on the ventral surface. After addition of NaB, SPARC expression increased and the pattern of expression shifted to one involving predominantly suprabasal cells (i.e., spinous cells, pre-CEs, and mature CEs). Dense deposits of SPARC often surrounded the mature CEs. Flow cytometric analysis indicated that approximately 13% of NHKs expressed SPARC within 24 h of seeding into culture. This fraction of SPARC+ cells increased with time and peaked immediately postconfluence (31.3 ± 6.3% SPARC+). Cellular SPARC expression then decreased to baseline levels during entrance into plateau phase growth. SPARC was detectable in all phases of the cell cycle. SPARC levels were more intense and heterogeneous within the G2/M and G1 phases while S phase cells exhibited relatively homogeneous, low intensity, SPARC expression. During NaB-induced NHK differentiation, SPARC intracellular content increased prior to the onset of CE formation (i.e., 2 days after its addition) followed by a period of extracellular accumulation which coincided with the time of maximal CE generation (i.e., Days 4 and 5 after NaB addition). Correlation of cell size with anti-SPARC immunoreactivity revealed a predominance of SPARC expression in cells with a suprabasal phenotype. NHKs cultured on fibronectin (FN), an established modulator of epidermal cell maturation in vitro, showed a similar response to NaB. In general, however, the level of NaB-induced SPARC expression was considerably reduced in FN cultures correlating with a lower efficiency of CE formation. Induced SPARC expression was, in large part, dependent on autocrine transforming growth factor-β (TGF-β) production since incubation in the presence of NaB + neutralizing antibodies to TGF-β inhibited both the expression of SPARC by 72% and development of mature CEs. 相似文献
8.
9.
This paper is dedicated as a token of homage and gratitude to Prof. Mu. En-zhi, the nestor in the field of graptolite studies, who introduced us chitinozoan studies with constant supports in many ways, and who died on 8th April, 1987. The Palaeontological Society of China has decided to publish a specieal volume in memory of this outstanding scientist. 相似文献
10.
单爪螯蜂属二新种:膜翅目:螯蜂科;单爪螯蜂亚科 总被引:2,自引:2,他引:0
本文记述单爪螯蜂属二新种;梳垫单瓜螯蜂Anteon pectinarolium,sp.nov。和滑盾单爪螯蜂Anteon blanduscutum,sp.nov。新种的模式标本保存在浙江农业大学植物保护系。 相似文献