l-Aspartate 4-decarboxylase catalyzes the conversion of aspartate to alanine and CO₂. The wild-type enzyme was observed as dodecamers at pH 5.0. The mutation of Ser298 into Arg resulted in an almost complete loss of the enzyme activity, and caused regional structural distortion and defects in the enzyme assembly, as shown in circular dichroism spectra and gel filtration profiles. Mutating Tyr207 and Pro257 into His also resulted in inactivation of the enzyme, but did not affect the overall structure. Computer modeling suggests that Ser298 is located on the surface, and its mutation may result in enzyme disassembly,...

To study the alkali denaturation of supercoiled DNA, plasmid pBR322 was treated with gradient concentrations of NaOH solution. The results of gel electrophoresis showed that the alkali denaturation of the supercoiled DNA occurred in a narrow range of pH value (12.88–12.90). The alkali-denatured supercoiled DNA ran, as a sharp band, faster than the supercoiled DNA. The supercoiled plasmid DNA of pBR322, pACYC184 and pJGX15A were denatured by NaOH, and then visualized by atomic force microscopy. Compared with the supercoiled DNA, the atomic force microscopy images of the alkali-denatured supercoiled DNA showed rough surface with many kinks, bulges on...

Histone lysine methylation is an evolutionally conserved modification involved in determining chromatin states associated with gene activation or repression. Here we report that the Arabidopsis SET domain group 8 (SDG8) protein is a histone H3 methyltransferase involved in regulating shoot branching. Knockout mutations of the SDG8 gene markedly reduce the global levels of histone H3 trimethylation at lysines 9 and 36 as well as dimethylation at lysine 36. The sdg8 mutants produce more shoot branches than wild-type plants. The expression of SPS/BUS (supershoot/bushy), a repressor of shoot branching, is decreased in sdg8 mutants,...

Neurodegenerative disorders such as Alzheimer’s, Huntington’s, and prion diseases are characterized by abnormal protein deposits in the brain of affected patients. In prion diseases, a key event in the pathogenesis is the conversion of the normal prion protein (PrP^c) into abnormal protease resistant PrP^Sc deposits, a phenomenon associated with a higher sensitivity to oxidative stress in vitro. In cellular models of Alzheimer and Huntington diseases, the disaccharide trehalose has been shown to be effective in inhibiting huntingtin and Aβ peptide aggregates and reducing their associated toxicity. We show in this study that trehalose treatment of...

Crk is a member of a family of adaptor proteins that are involved in intracellular signal pathways altering cell adhesion, proliferation, and migration. Increased expression of Crk has been described in lung cancer and associated with increased tumor invasiveness. MicroRNAs (miRNAs) are a family of small non-coding RNAs (approximately 21–25 nt long) that are capable of targeting genes for either degradation of mRNA or inhibition of translation. Crk is a predicted putative target gene for miR-126. Over-expression of miR126 in a lung cancer cell line resulted in a decrease in Crk protein without any alteration in the associated...

Recombinant fusion proteins containing the aa 286–426 of the dengue envelope protein fused to P64k protein from Neisseria meningitidis have been previously reported. Particularly, the immunogenicity and protective capacity of the dengue 2 recombinant protein was demonstrated in Macaca fascicularis monkeys. Here we evaluate the recombinant fusion protein containing the domain III of the dengue 1 envelope protein (PD10) in non-human primates (M. fascicularis and rhesus monkeys) and compare the effect of aluminum hydroxide and Freund adjuvant on the immunity induced. The PD10 protein emulsified in Freund adjuvant was highly immunogenic in M. fascicularis...