Isolation and cDNA cloning of an Em-like protein from mung bean (Vigna radiata) axes

Until now no 'early-methionine-labelled' (Em) proteins have been reported in the Fabaceae. To check whether a previously isolated low-molecular mass albumin from dry mung bean embryonic axes possibly corresponded to an Em-like protein, the protein was purified, sequenced and its cDNA clone isolated and characterized. N-terminal sequencing of cyanogen bromide cleavage products of the protein revealed homology with previously described Em-like proteins from other species. Analysis of cDNA clones encoding the mung bean Em protein revealed the presence of two classes of Em proteins and confirmed their homology to the previously characterized Em-like proteins. In vivo labelling and northern blot analysis further demonstrated that the mung bean protein is synthesized during early germination of the axes and that abscisic acid (ABA) extends its synthesis. It appears, therefore, that legumes also contain maturation-specific, ABA-responsive Em-like proteins.     

SSA/Ro52 autoantigen interacts with Dcp2 to enhance its decapping activity

We identified human decapping enzyme 2 (hDCP2) as a binding protein with Ro52, being colocalized in processing bodies (p-bodies). We also showed that the N-terminus and C-terminus of Ro52 bound to hDCP2. Moreover, Ro52 enhanced decapping activity of hDCP2 in a dose-dependent manner. Our data support the novel notion of the association between Ro52 with hDCP2 protein in cytoplasmic p-bodies, playing a role in mRNA metabolism in response to cellular stimulation.     

醛固酮对心室成纤维细胞分泌内皮素的影响

用细胞培养、内皮素放射免疫测定和RT-PCR的方法,探讨醛固酮对心室成纤维细胞分泌内皮素的影响。结果显示,醛固酮(1×10     

Novel Alternative Splicing Predicts a Truncated Isoform of the NMDA Receptor Subunit 1 (NR1) in Embryonic Rat Brain

The expression of mesencephalic brain derived neurotrophic factor (BDNF) has been shown to be regulated by dopaminergic neuronal functioning and glutamate receptors (GluRs). In turn, BDNF participates in the regulation of mesencephalic GluRs’ expression. In the present study we analyzed, using semi-quantitative RT-PCR, the effect of BDNF as well as of the GluRs agonists NMDA and trans-(±)-1-Amino-(1S,3R)-cyclopentane dicarboxylic acid (t-ACPD), on the expression levels of the NMDA GluR subunit 1 (NR1) mRNA, using rat cultured mesencephalic neurons. In the course of this study, a novel rat mRNA splice variant of NR1 was identified. This new NR1 mRNA isoform is characterized by the insertion of an 82 base pair intron containing an inframe stop codon, thus predicting the expression of a putative truncated protein of 465 amino acids. The RT-PCR and in situ hybridization reveals that the novel NR1 mRNA is expressed in various brain regions of the rat embryo, whereas no expression was detected in the adult rat brain. The modulation of the novel NR1 mRNA isoform by both BDNF and the metabotropic GluR agonist t-ACPD, suggests that the resulting putative NR1 truncated protein may be relevant in the regulatory network of glutamatergic neurotransmission in the developing central nervous system.     

细胞生物活性肽-蛋氨酸脑啡肽对小鼠CD4~+T细胞mRNA的影响

从基因水平探讨蛋氨酸脑啡肽对小鼠CD4'T细胞mRNA转录的影响。6～8周龄BALB/c雌性小鼠体内、外不同浓度MEK刺激。采用RT-PCR技术检测mRNA,所得不同浓度MEK刺激的CD4+T细胞mRNA和β-actin条带密度比值作为相对表达强度,所得数据采用SPSS11.5软件进行统计分析。4mg/mLMEK体内刺激及10-9～10-12mol/mL的MEK体外刺激促进小鼠CD4'T细胞mRNA转录;10-1～10-8mol/mL的MEK抑制小鼠CD4+T细胞mRNA的转录。10-13～10-14mol/mL的MEK对小鼠CD4'T细胞mRNA的转录无明显变化。适量浓度的MEK体内、外刺激能促进小鼠CD4+T细胞mRNA转录的高效表达。