In snapdragon flowers, the volatile ester methyl benzoate is the most abundant scent compound. It is synthesized by and emitted from only the upper and lower lobes of petals, where pollinators (bumblebees) come in contact with the flower. Emission of methyl benzoate occurs in a rhythmic manner, with maximum emission during the day, which correlates with pollinator activity. A novel S -adenosyl-L -methionine:benzoic acid carboxyl methyl transferase (BAMT), the final enzyme in the biosynthesis of methyl benzoate, and its corresponding cDNA have been isolated and characterized. The complete amino acid sequence of the BAMT protein has only low levels of sequence similarity to other previously characterized proteins, including plant O -methyl transferases. During the life span of the flower, the levels of methyl benzoate emission, BAMT activity, BAMT gene expression, and the amounts of BAMT protein and benzoic acid are developmentally and differentially regulated. Linear regression analysis revealed that production of methyl benzoate is regulated by the amount of benzoic acid and the amount of BAMT protein, which in turn is regulated at the transcriptional level.

In snapdragon flowers, the volatile ester methyl benzoate is the most abundant scent compound. It is synthesized by and emitted from only the upper and lower lobes of petals, where pollinators (bumblebees) come in contact with the flower. Emission of methyl benzoate occurs in a rhythmic manner, with maximum emission during the day, which correlates with pollinator activity. A novel S-adenosyl-l-methionine:benzoic acid carboxyl methyl transferase (BAMT), the final enzyme in the biosynthesis of methyl benzoate, and its corresponding cDNA have been isolated and characterized. The complete amino acid sequence of the BAMT protein has only low levels of sequence similarity to other previously characterized proteins, including plant O-methyl transferases. During the life span of the flower, the levels of methyl benzoate emission, BAMT activity, BAMT gene expression, and the amounts of BAMT protein and benzoic acid are developmentally and differentially regulated. Linear regression analysis revealed that production of methyl benzoate is regulated by the amount of benzoic acid and the amount of BAMT protein, which in turn is regulated at the transcriptional level.

Parkinson's disease (PD) is a neurologic disorder characterized by dopaminergic cell death in the substantia nigra. PD pathogenesis involves mitochondrial dysfunction, proteasome impairment, and α-synuclein aggregation, insults that may be especially toxic to oxidatively stressed cells including dopaminergic neurons. The enzyme methionine sulfoxide reductase A (MsrA) plays a critical role in the antioxidant response by repairing methionine-oxidized proteins and by participating in cycles of methionine oxidation and reduction that have the net effect of consuming reactive oxygen species. Here, we show that MsrA suppresses dopaminergic cell death and protein aggregation induced by the complex I inhibitor rotenone or mutant α-synuclein, but not by the proteasome inhibitor MG132. By comparing the effects of MsrA and the small-molecule antioxidants N-acetyl-cysteine and vitamin E, we provide evidence that MsrA protects against PD-related stresses primarily via methionine sulfoxide repair rather than by scavenging reactive oxygen species. We also demonstrate that MsrA efficiently reduces oxidized methionine residues in recombinant α-synuclein. These findings suggest that enhancing MsrA function may be a reasonable therapeutic strategy in PD. Keywords aggresome; dopamine; glutathione; heat shock protein; methionine sulfoxide reductase; neurodegeneration; oxidative stress; Parkinson's disease; proteasome; protofibril; rotenone; synuclein Parkinson's disease (PD) is a neurologic disorder that involves a selective loss of dopaminergic neurons from the substantia nigra [1,2]. The postmortem brains of PD patients are characterized by reduced activity of mitochondrial complex I, an enzyme of the mitochondrial electron transport chain [3,4]. In turn, this defect may cause a 'leakage' of electrons from mitochondria, leading to the accumulation of reactive oxygen species (ROS) that damage *Corresponding author. Address: Jean-Christophe Rochet, Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, 575 Stadium Mall Drive, RHPH 410A, West Lafayette, Indiana, 47907-209147907- . Fax: 765-494-1414. E-mail: rochet@pharmacy.purdue.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author ManuscriptFree Radic Biol Med. Author manuscript; available in PMC 2009 August 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript proteins, lipids, and nucleic acids [3,5]. The brains of PD patients also show evidence of impaired proteasomal function [6], a defect that results in increased oxidative stress and decreased elimination...

A series of near-isogenic glycinebetaine-containing and -deficient F, pairs of Zea mays 1. (maize) lines were developed. The pairs of lines differ for alternative alleles of a single locus; the wild-type allele conferring glycinebetaine accumulation is designated Betl and the mutant (recessive) allele is designated betl. The nearisogenic lines were used to investigate whether glycinebetaine deficiency affects the pool size of the glycinebetaine precursor, choline, using a new method for glycinebetaine and choline determination: stable isotope dilution plasma desorption mass spectrometry. Glycinebetaine deficiency in maize was associated with a significant expansion of the free choline pool, but the difference in choline pool size was not equal to the difference in glycinebetaine pool size, suggesting that choline must down-regulate its own synthesis. Consistent with this, glycinebetaine deficiency was also associated with the accumulation of the choline precursor, serine. A randomly amplified polymorphic DNA marker was identified that detects the betl allele. In 62 F, families tested the 10-mer primer 5'-GTCCTCGTAG produced a 1.2-kb polymerase chain reaction product only when DNA from Betl/betl or betl/betl lines was used as template. AI1 26 homozygous Betl/Betl F, families tested were null for this marker.It is now well established that betaines and their sulfonio analogs can play important roles in osmotic adjustment and/or osmoprotection in bacteria (Csonka and Hanson, 1991), cyanobacteria (Borowitzka, 1986), marine algae (Blunden and Gordon, 1986), and mammals (Garcia-Perez and Burg, 1991) (see Yancey [1994] for a recent review of the role of betaines and their sulfonio analogs as compatible solutes). It is probable that these compounds have similar functions in higher plants (Robinson and Jones, 1986;Rhodes and Hanson, 1993). Toward the goal of genetically testing the role of glycinebetaine in osmotic stress resistance in maize (Zea mays L.), we have developed a series of near-

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tion, many organisms synthesize solutes that either help retain water within cells or protect cellular components Glycinebetaine (GB) accumulation has been suggested to be an from injury caused by dehydration. One such solute, glyadaptive response to several abiotic environmental stresses. Genetic cinebetaine (GB) has been shown to act in both capacitand metabolic studies of GB accumulation in maize (Zea mays L.) indicate that recessive alleles of a single locus are responsible for the

Nanoparticulate drug carriers exploit the enhanced permeability of tumor vasculature to achieve selective delivery of chemotherapeutic drugs. For this purpose, nanoparticles (NPs) need to circulate with a long half-life, enter tumors via the permeable vasculature and stay in tumors via favorable interactions with tumor cells. To fulfill these requirements, albumin-coated nanocrystal formulation of paclitaxel (PTX), Cim-F-alb, featuring high drug loading content, physical stability in serum, and surface-bound albumin in its native conformation is prepared. The pharmacokinetic and biodistribution (PK/BD) profiles of Cim-F-alb in a mouse model of B16F10 melanoma show that Cim-F-alb exhibits a longer plasma half-life and a greater PTX deposition in tumors than Abraxane by ~1.5 and ~4.6 fold, respectively. Biolayer interferometry analysis indicates that Cim-F-alb has less interaction with serum proteins than nanocrystals lacking albumin coating, indicating the protective effect of the surface-bound albumin against opsonization in the initial deposition phase. With the advantageous PK/BD profiles, Cim-F-alb shows greater and longer-lasting anti-cancer efficacy than Abraxane at the equivalent dose. This study demonstrates the significance of controlling circulation stability and surface property of NPs in efficient drug delivery to tumors and enhanced anti-cancer efficacy.

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