Gibberellin A(3) Is Biosynthesized from Gibberellin A(20) via Gibberellin A(5) in Shoots of Zea mays L

[17-¹³C,³H]-Labeled gibberellin A₂₀ (GA₂₀), GA₅, and GA₁ were fed to homozygous normal (+/+), heterozygous dominant dwarf (D8/+), and homozygous dominant dwarf (D8/D8) seedlings of Zea mays L. (maize). ¹³C-Labeled GA₂₉, GA₈, GA₅, GA₁, and 3-epi-GA₁, as well as unmetabolized [¹³C]GA₂₀, were identified by gas chromatography-selected ion monitoring (GC-SIM) from feeds of [17-¹³C, ³H]GA₂₀ to all three genotypes. ¹³C-Labeled GA₈ and 3-epi-G₁, as well as unmetabolized [¹³C]GA₁, were identified by GC-SIM from feeds of [17-¹³C, ³H]GA₁ to all three genotypes. From feeds of [17-¹³C, ³H]GA₅, ¹³C-labeled GA₃ and the GA₃-isolactone, as well as unmetabolized [¹³C]GA₅, were identified by GC-SIM from +/+ and D8/D8, and by full scan GC-MS from D8/+. No evidence was found for the metabolism of [17-¹³C, ³H]GA₅ to [¹³C]GA₁, either by full scan GC-mass spectrometry or by GC-SIM. The results demonstrate the presence in maize seedlings of three separate branches from GA₂₀, as follows: (a) GA₂₀ → GA₁ → GA₈; (b) GA₂₀ → GA₅ → GA₃; and (c) GA₂₀ → GA₂₉. The in vivo biogenesis of GA₃ from GA₅, as well as the origin of GA₅ from GA₂₀, are conclusively established for the first time in a higher plant (maize shoots).     

Monogamy and long-term pair bonding in vertebrates

The term 'monogamy' represents a complex of mating systems that has been relalively neglected. Monogamy is generally associated with significant biparental care and is most common among birds. Recent work has addressed such aspects as the evolutionary incentives for (and value of) contributions by the male parent, how the distributions of females and critical nesting resources can promote monogamy, male defense of genetic paternity, the causes of long-term mate-retention in certain species, and the subtle means by which sexual selection operates within basically monogamous systems. New advances in testing genetic relatedness, especially DNA fingerprinting, promise much for the assessment of individual costs and benefits of monogamy.     

Regional changes in muscle mass and strength following 20 days of bed rest, and the effects on orthostatic tolerance capacity in young subjects

To this day, many studies have suggested that prolonged bed rest (BR) affects on muscle mass and strength not only in gravity muscles but also in ungravity muscles. However, it is still unclear whether the decrease in regional muscle strength after BR is due to the alterations in the corresponding muscle mass, or not. On the other hand, if BR decreases the mass of antigravity muscles (UGM) as well as muscle strength and then increases tissue compliance of the antigravity muscles, orthostatic tolerance capacity will be decreased by the reduction in cardiac output (CO) in spite of the increase in myocardial contractility because the more decrease in venous return due to the more increase in blood pooling within the compliant tissues of the lower body. However, this is also unclear. To make these questions clear, the present study investigated the regional muscle mass and strength and orthostatic tolerance capacity before and after 20 days of bed rest in young subjects.     

Biosynthesis of brassinolide from castasterone in cultured cells of Catharanthus roseus

Feeding experiments with tritium- and deuterium-labeled castasterone (CS) were conducted with three cell lines of Catharanthus roseus, including crown gall cells and nontransformed cells. In all three cell lines, the conversion of CS to brassinolide (BL) was observed and unequivocally confirmed by gas chromatography/mass spectrometry (GC/MS). This is the first conclusive evidence that CS is the biosynthetic precursor of BL.Biosynthesis of brassinosteroids in Catharanthus roseus. Part II. Part I of this series: Yokota et al. (1990a).     

Controlled release of adeno-associated virus from alginate hydrogel microbeads with enhanced sensitivity to ultrasound

Adeno-associated virus (AAV)-based gene therapy holds promise as a fundamental treatment for genetic disorders. For clinical applications, it is necessary to control AAV release timing to avoid an immune response to AAV. Here we propose an ultrasound (US)-triggered on-demand AAV release system using alginate hydrogel microbeads (AHMs) with a release enhancer. By using a centrifuge-based microdroplet shooting device, the AHMs encapsulating AAV with tungsten microparticles (W-MPs) are fabricated. Since W-MPs work as release enhancers, the AHMs have high sensitivity to the US with localized variation in acoustic impedance for improving the release of AAV. Furthermore, AHMs were coated with poly-l -lysine (PLL) to adjust the release of AAV. By applying US to the AAV encapsulating AHMs with W-MPs, the AAV was released on demand, and gene transfection to cells by AAV was confirmed without loss of AAV activity. This proposed US-triggered AAV release system expands methodological possibilities in gene therapy.     

Plasmodium falciparum protein associated with the invasion junction contains a conserved oxidoreductase domain

The merozoite cap protein-1 (MCP-1) of Plasmodium falciparum follows the distribution of the moving Junction during invasion of erythrocytes. We have cloned the gene encoding this protein from a cDNA library using a monoclonal antibody. The protein lacks a signal sequence and has no predicted trans-membrane domains; none of the antisera reacts with the surfaces of intact merozoites, indicating that the cap distribution is submembranous. MCP-1 is divided into three domains. The N-terminal domain includes a 52-amino-acid region that is highly conserved in a large family of bacterial and eukaryotic proteins. Based on the known functions of two proteins of this family and the pattern of amino acid conservation, it is predicted that this domain may possess oxido-reductase activity, since the active cysteine residue of this domain is invariant in all proteins of the family. The other two domains of MCP-1 are not found in any other members of this protein family and may reflect the specific function of MCP-1 in invasion. The middle domain is negatively charged and enriched in glutamate; the C-terminal domain is positively charged and enriched in lysine. By virtue of its positive charge, the C-terminal domain resembles domains in some cytoskeleton-associated proteins and may mediate the interaction of MCP-1 with cytoskeleton in Plasmodium.     

Seven guaianolides from Eupatorium chinense

Two allyl hydroperoxy guaianolide sesquiterpene lactones (peroxyeupahakonin-A and -B) and five new guaianolides (eupahakonin-A and -B, eupahakonenin-A and -B, and eupahakonesin) were isolated from E. chinense and characterized. The allyl hydroperoxy sesquiterpene lactones were characterized by spectral and chemical methods. They were prepared chemically by photosensitized oxygenation of eupahakonin-A.     

(+)-Arctigenin,a lignan from Wikstroemia indica

A new lignan, (+)-aretigenin has been isolated from the roots of Wikstroemia indica (Nan-Ling-Jao-Hua) and identified as 8(R) 8′(S)-4′-hydroxy-3, 4,3′-trimethoxylignan-olid (9, 9′) on the basis of spectral evidence as well as a direct comparison with its enantiomer, (?)-arctigenin.     

15-Acetoxycostunolide from Magnolia sieboldii

A new germacranolide isolated from M. sieboldii was shown to be 15-acetoxycostunolide by spectroscopic and chemical methods. ¹H NMR spin decoupling and NOE experiments in the presence of a lanthanide shift reagent were used for structure elucidation.