Genetic polymorphisms of blood proteins in the troops of Japanese macaques,Macaca fuscata: IV. Erythrocyte esterase polymorphism inMacaca fuscata

Genetic variation at the locus controlling A₁ band of erythrocyte esterase was found in the Japanese macaque,Macaca fuscata. Existence of four alleles,Es-A ₁ ¹ ,Es-A ₁ ² ,Es-A ₁ ³ , andEs-A ₁ ⁴ , controlling the mobility of the band and codominance relation between them were postulated. A majority of the troops examined were monomorphic inEs-A ₁ 1-1 phenotype, and the variant phenotypes were observed to occur only in Yugawara-Ihama, Arashiyama, and Koshima areas.     

Carbohydrate composition of the isolated cell walls of dermatophytes

In an attempt to evaluate taxonomic character of sugar composition of dermatophytes, the purified cell walls from 13 species are analyzed on neutral sugar composition by gas liquid chromatography. The results were principally compatible with those obtained by conventional morphological examination. Neutral sugar components of dermatophytes cell walls were mannose and glucose in the ratio of 1∶2.7 for Epidermophyton and 1∶1.4 for Microsporum. There were two types in Trichophyton, in which the ratios of mannose to glucose were 1∶1.6 and 1∶3.8. The cases of Trichophyton ferrugineum and Trichophyton mentagrophytes were exceptional. The ratio of the former was 1∶1.4, which implied the relation to Microsporum group, and the ratio of the latter was 1∶2.3, which was supposed to be the intermediate of two types of Trichophyton group. Albino type cell wall of Epidermophyton floccosum was more rich in glucose than pigmented type one.     

Experimental Approach Reveals the Role of alx1 in the Evolution of the Echinoderm Larval Skeleton

Over the course of evolution, the acquisition of novel structures has ultimately led to wide variation in morphology among extant multicellular organisms. Thus, the origins of genetic systems for new morphological structures are a subject of great interest in evolutionary biology. The larval skeleton is a novel structure acquired in some echinoderm lineages via the activation of the adult skeletogenic machinery. Previously, VEGF signaling was suggested to have played an important role in the acquisition of the larval skeleton. In the present study, we compared expression patterns of Alx genes among echinoderm classes to further explore the factors involved in the acquisition of a larval skeleton. We found that the alx1 gene, originally described as crucial for sea urchin skeletogenesis, may have also played an essential role in the evolution of the larval skeleton. Unlike those echinoderms that have a larval skeleton, we found that alx1 of starfish was barely expressed in early larvae that have no skeleton. When alx1 overexpression was induced via injection of alx1 mRNA into starfish eggs, the expression patterns of certain genes, including those possibly involved in skeletogenesis, were altered. This suggested that a portion of the skeletogenic program was induced solely by alx1. However, we observed no obvious external phenotype or skeleton. We concluded that alx1 was necessary but not sufficient for the acquisition of the larval skeleton, which, in fact, requires several genetic events. Based on these results, we discuss how the larval expression of alx1 contributed to the acquisition of the larval skeleton in the putative ancestral lineage of echinoderms.     

Decreased Expression of Matrix Metalloproteinase-9 and Increased Expression of Tissue Inhibitors of Matrix Metalloproteinase-1 in Paratuberculosis-Infected Cattle in the ELISA-Negative Subclinical Stage

We investigated the gene expression of matrix metalloproteinases-9 (MMP-9) and tissue inhibitors of matrix metalloproteinases-1 (TIMP-1) in peripheral blood cells from infected cattle with Mycobacterium avium subsp. paratuberculosis (Map) in the ELISA-negative subclinical stage compared with uninfected control cattle. Significant decreased MMP-9 expression and increased TIMP-1 expression were found in peripheral blood cells from Map-infected cattle after stimulation with Map lysate and Map purified protein derivative (PPD) than in control cattle by real-time RT-PCR analysis. In contrast to the uninfected controls, the activity of MMP-9 was also decreased in peripheral blood cell culture supernatants from Map-infected cattle at 24 hr after Map lysate and MapPPD stimulation by gelatin zymography analysis. As a result, the MMP-9 may play an important role in the development of Mycobacterium avium subsp. paratuberculosis disease.     

Osmotic Stress Responses and Plant Growth Controlled by Potassium Transporters in Arabidopsis

Osmotic adjustment plays a fundamental role in water stress responses and growth in plants; however, the molecular mechanisms governing this process are not fully understood. Here, we demonstrated that the KUP potassium transporter family plays important roles in this process, under the control of abscisic acid (ABA) and auxin. We generated Arabidopsis thaliana multiple mutants for K⁺ uptake transporter 6 (KUP6), KUP8, KUP2/SHORT HYPOCOTYL3, and an ABA-responsive potassium efflux channel, guard cell outward rectifying K⁺ channel (GORK). The triple mutants, kup268 and kup68 gork, exhibited enhanced cell expansion, suggesting that these KUPs negatively regulate turgor-dependent growth. Potassium uptake experiments using ⁸⁶radioactive rubidium ion (⁸⁶Rb⁺) in the mutants indicated that these KUPs might be involved in potassium efflux in Arabidopsis roots. The mutants showed increased auxin responses and decreased sensitivity to an auxin inhibitor (1-N-naphthylphthalamic acid) and ABA in lateral root growth. During water deficit stress, kup68 gork impaired ABA-mediated stomatal closing, and kup268 and kup68 gork decreased survival of drought stress. The protein kinase SNF1-related protein kinases 2E (SRK2E), a key component of ABA signaling, interacted with and phosphorylated KUP6, suggesting that KUP functions are regulated directly via an ABA signaling complex. We propose that the KUP6 subfamily transporters act as key factors in osmotic adjustment by balancing potassium homeostasis in cell growth and drought stress responses.     

The influence of blood glucose on neutrophil function in individuals without diabetes

We assessed the association of neutrophil function with glycated hemoglobin (HbA1c) levels in a Japanese general population. Participants were 809 males and females who were over 20 years old living in the Iwaki region in Aomori Prefecture located in northern Japan. Lifestyle parameters (smoking, alcohol consumption, and exercise habits), HbA1c and neutrophil function such as reactive oxygen species (ROS) production capability and phagocytic activity (PA) were measured. ROS production capability was measured before and after phagocytic stimulus to obtain basal ROS production and stimulated ROS production. Level of HbA1c had a positive correlation with basal ROS production (p=0.053), a negative correlation with stimulated ROS production (p=0.072) and PA (p=0.059) only in post‐menopausal groups, and not in pre‐menopausal groups. However, there were no correlations between levels of HbA1c and neutrophil functions in male. In conclusion, in the present study, despite the presence of diabetes, chronic hyperglycemia was found to cause an increase in daily basal ROS production of neutrophils, and increased susceptibility to infection caused by reduced neutrophilic reaction in females in their menopause. Therefore, from the oxidative point of view, strict glycemic control is necessary to prevent post‐menopausal females from developing diabetic complications in spite of the presence of diabetes.     

Molecular Conformation of 2′-Deoxy-2′-methylidene-cytidine: A Potent Antineoplastic Nucleoside

Abstract

2′-Deoxy-2′-methylidenecytidine (DMDC), a potent inhibitor of the growth of tumor cells, was crystallized with two different forms. One is dihydrated (DMDC·2H₂O) and the other is its hydrochloride salt (DMDC·HCLl). Both crystal and molecular structures have been determined by the X-ray diffraction method. In both forms the glycosidic and sugar conformations are anti and C(4′)-exo, respectively, whereas the conformation about the exocyclic bond is trans for DMDC·2H₂O and gauche ⁺ for DMDC·HCl. Proton nuclear magnetic resonance data of DMDC indicate a preference for the anti C(4′)-exo conformation found in the solid state. These molecular conformations were compared with the related pyrimidine nucleosides. When the cytosine bases are brought into coincidence, DMDC displays the exocyclic C(4′)-C(5′) bond located on the very close position to those of pyrimidine nucleosides with typical overall conformations. On the other hand, the hydroxyl O(3′)-H groups are separated by ca. 3 Å in the cases of DMDC and other pyrimidine nucleosides which have the C(2′)-endo sugar conformation. This result may be useful for the implication about the mechanism of the biological activity of DMDC.     

Two Types of Alpha Satellite DNA in Distinct Chromosomal Locations in Azara's Owl Monkey

Alpha satellite DNA is a repetitive sequence known to be a major DNA component of centromeres in primates (order Primates). New World monkeys form one major taxon (parvorder Platyrrhini) of primates, and their alpha satellite DNA is known to comprise repeat units of around 340 bp. In one species (Azara''s owl monkey Aotus azarae) of this taxon, we identified two types of alpha satellite DNA consisting of 185- and 344-bp repeat units that we designated as OwlAlp1 and OwlAlp2, respectively. OwlAlp2 exhibits similarity throughout its entire sequence to the alpha satellite DNA of other New World monkeys. The chromosomal locations of the two types of sequence are markedly distinct: OwlAlp1 was observed at the centromeric constrictions, whereas OwlAlp2 was found in the pericentric regions. From these results, we inferred that OwlAlp1 was derived from OwlAlp2 and rapidly replaced OwlAlp2 as the principal alpha satellite DNA on a short time scale at the speciation level. A less likely alternative explanation is also discussed.     

Plant communities and environmental factors in the Guayana Highlands: monitoring for conservation under future climate change

The Guayana Highlands (GH) constitute a highly diverse, but relatively poorly studied Neotropical biome, comprised of ～50 flat-topped mountain summits (called tepuis). Previous studies based on warming forecasts for the region suggested that an upward displacement of environmental conditions of 500–700 m could occur by 2100, potentially resulting in the extinction of c. 50% of its endemic flora due to total habitat loss. To assess the ecological responses of the species to climate change, and select the appropriate conservation measures, long-term monitoring of the GH plant communities will be necessary. In this study, the baseline state for future comparisons was established for the best explored tepui in terms of its flora, Roraima-tepui (2810 m), through a floristic characterization of its different vegetation types. We also identified the environmental gradients underlying the major plant communities, and assessed the effects of human activities on the chemistry of soils and water at three field camps. Our results yielded five main community types: three meadows, one shrubland, and one forest, with their corresponding diagnostic species. The herbaceous communities were mainly influenced by the presence of flat sandy soils, with varying flooding capacity. Shrublands and forests were characterized by irregular organic soils with very low pH. Finally, pH values below 3 were measured on an organic soil of a field camp, although further studies will be necessary to attribute this deviation to human activities.