Effects of phytosulfokine-α on growth and tropane alkaloid production in transformed roots of Atropa belladonna

Phytosulfokine (PSK)- is a sulphated pentapeptide, isolated fromthe medium of cultured Asparagus officinalis mesophyllcells, that promotes cell proliferation. It is a putative key factor inconditioned medium required for the growth of low-density plant cell cultures.The present study investigates the effect of PSK- on growth and tropanealkaloid production in Atropa belladonna hairy rootstransformed with Agrobacterium rhizogenes (MAFF 03-01724). Although the growth rates ofhairy roots cultured in medium with orwithout PSK- for 4 weeks did not show any differences, the productivityof tropane alkaloids, especially of hyoscyamine, was enhanced by10^–7 or 10^–8 M PSK-. Inaddition, the content of tropane alkaloids in transformed roots treated withPSK- was 1.4 times higher than that of untreated roots after 4 weeks ofculture. The time course of growth and tropane alkaloid production inAtropa belladonna transformed roots suggested thatPSK- influenced the growth of transformed roots during the activegrowingphase, but not tropane alkaloid production.     

The obesity in bilateral ovariectomized rats is related to a decrease in the expression of leptin receptors in the brain.

We investigated the expression levels of leptin receptors in the brain of ovariectomized (OVX) rats. The mean expression level of ob mRNA in adipose tissues of OVX rats was significantly (P < 0.01) lower than that in the SHAM operation group rats, and the mean body weight of OVX rats was significantly (P < 0.01) greater than that in the SHAM group rats. However, there were no differences between serum leptin concentrations in these two groups. The mean level of leptin receptor (OB-R) mRNA expression in the brain tissue and the mean level of long form type OB-R (OB-RL) mRNA expression in the hypothalamus of the OVX rats were significantly (P < 0.05) lower than those in the SHAM group rats. These changes were cancelled by supplementation with 17 beta-estradiol in OVX rats. These results suggested that not only changes in the expression level of ob mRNA in adipose tissue and the serum leptin concentration but also changes in the OB-R mRNA in the brain are involved in the body weight increase in OVX rats and that a decrease in OB-R makes transmission of signals to suppress the amount of food intake difficult, thus leading to an increase in body weight.     

Thelephantins D-H: five p-terphenyl derivatives from the inedible mushroom Thelephora aurantiotincta

Five p-terphenyl derivatives named thelephantins D-H (1-5) together with nine known compounds, thelephantins A-C (6-8), ganbajunin E (9), p-hydroxylbenzoic acid (10), ganbajunin C (11), thelephorin A (12), 2-O-methylatromentin (13) and atromentin (14), were isolated from the methanolic extract of fruit bodies of the Thelephoraceous Basidiomycete Thelephora aurantiotincta. Their structures were elucidated by high-resolution MS, 2D NMR, IR and UV spectroscopic analysis.     

4-Hydroxybenzyl alcohol accumulates in flowers and developing fruits of carrot and inhibits seed formation

Somatic embryogenesis in carrot (Daucus carota) is autonomously inhibited by 4-hydroxybenzyl alcohol (4HBA), which is produced by embryogenic cells. Because somatic embryogenesis is used as a model of zygotic embryogenesis, we assayed for 4HBA in carrot seeds and analyzed the effect of 4HBA on seed formation to determine whether 4HBA is also produced during zygotic embryogenesis. HPLC analysis showed that 4HBA accumulated in flowers and immature and mature fruits, but not in vegetative tissues. The concentration of 4HBA was highest after flowering, when the zygote developed into the early globular-stage embryo. 4HBA accumulation then decreased with seed development. Exogenous application of 4HBA to immature carrot fruits inhibited seed formation. Many 4HBA-treated seeds did not include a mature embryo. These results indicate that the production and accumulation of 4HBA occurs during carrot seed development and that 4HBA has an inhibitory effect on carrot seed formation.     

Kinetic and site-directed mutagenesis studies of prevotella intermedia acid phosphatase

Site-directed mutagenesis was used to examine the roles of the conserved histidine, arginine and cysteine residues in acid phosphatase from Prevotella intermedia (PiACP). The replacement of histidine and arginine residues resulted in the elimination of the PiACP activity while the cysteine mutants retained activity. These results suggest that the histidine and arginine residues are essential for catalysis.     

Neonatal presentation of adult-onset type II citrullinemia

Adult-onset type II citrullinemia (CTLN2) is characterized by a liver-specific argininosuccinate synthetase deficiency caused by a deficiency of the citrin protein encoded by the SLC25A13 gene. Until now, however, no SLC25A13 mutations have been reported in children with liver diseases. We described three infants who presented as neonates with intrahepatic cholestasis associated with hypermethioninemia or hypergalactosemia detected by neonatal mass screening. DNA analyses of SLC25A13 revealed that one patient was a compound heterozygote for the 851de14 and IVS11+IG-->A mutations and two patients (siblings) were homozygotes for the IVS11+lG-->A mutation. These results suggested that there may be a variety of liver diseases related to CTLN2 in children.     

Suppression of Fas-mediated hepatic apoptosis by caspase inhibitor-encapsulated nanoparticles bearing poly-(N-p-vinylbenzyl-O-β-D-galactopyranosyl-[1-4]-D-gluconamide)

To develop a drug delivery system for acute hepatic injury, we prepared Z-Asp, a general caspase inhibitor, encapsulated in poly (DL-lactic-co-glycolic acid) (50:50) (mol/mol) nanoparticles bearing poly-(N-p-vinylbenzyl-O--d-galactopyranosyl-[1-4]-d-gluconamide) (PVLA) on their surface. These nanoparticles specifically interacted with the primary cultured hepatocytes via the asialoglycoprotein receptors on surface and effectively inhibited the fulminant hepatic cell death induced by anti-mouse Fas antibody while these particles did not affect the cell death of an asialoglycoprotein receptor null cell line, A20. These nanoparticles are thus a promising therapy for acute liver injury.     

Iron accumulation in tobacco plants expressing soyabean ferritin gene

High iron-content transgenic tobacco plants have been produced by transfer via Agrobacterium tumefaciens of soyabean ferritin cDNA under the control of a CaMV 35S promoter. Immunoblot analysis of protein from transgenic tobacco plants suggested mature ferritin subunits are produced by cleavage of transit peptides. The expressed ferritin was observed in the tissues of leaves and stems. The maximal iron content of transformant leaves was approximately 30% higher than leaves from non-transformants. The increased iron content of each transformant was correlated with increases in ferritin content. These results demonstrate the potential of breeding high iron content crops by introduction of the ferritin gene