Somatic Embryogenesis in Cultured Carrot Cells

Somatic embryogenesis in cultured plant cells is an ideal system for investigating the whole process of differentiation and development from single cells to whole plants, and especially the molecular mechanism of expression of totipotency. This review reports recent progress the studies on somatic embryogenesis.     

Structure of the “Peroxy-Y Base” from Liver tRNA<Superscript>Phe</Superscript>

WE wish to report that reconstituted sperm whale myoglobin prepared by the method of Breslow¹ (except that pH 2 was found sufficient to remove all the haem) (I) crystallizes² in a different habit from those prepared by the method of Rossi-Fanelli et al.³ (II) using haemin of Sigma lot 77B-0220 and our own ⁵⁷Fe photoporphyrin preparation and the native myoglobin (III). Although all three form type A³ monoclinic prisms, the best developed plane is [001] for II and III, it is [100] for I. There seems to be great interest in reconstituted haemoproteins^4,5, so it is important that crystallization habit may be a sensitive test for subtle changes in protein structures.     

Potential fragmentation and loss of thermal habitats for charrs in the Japanese archipelago due to climatic warming

1. The upper thermal limits of the present distributions of two charr species, Dolly Varden, Salvelinus malma , and white-spotted charr, S. leucomaenis , in streams of the Japanese archipelago were examined using groundwater temperature as an index of thermal condition. The lower limits of the altitudinal distributions of Dolly Varden and white-spotted charr were delineated, respectively, by 8 and 16 °C groundwater isotherms.
2. The potential impact of future climatic warming on the geographical distribution, habitat extent and population fragmentation of each species was predicted at both the full archipelago and individual catchment levels.
3. For Dolly Varden, analysis at the full archipelago level indicated a loss of 27.6, 67.2, 79.6 and 89.6% of the current geographical range, respectively, for a 1, 2, 3 and 4 °C increase in mean annual air temperature. The present distribution area of white-spotted charr would likewise reduce by 4.1, 20.5, 33.8 and 45.6%, respectively.
4. Based on the analyses of three individual catchments, one for Dolly Varden and two for white-spotted charr, the lower habitat boundaries for the two charr species could be expected to rise increasingly to higher elevations in each catchment as warming proceeded. As a consequence, there would be large reductions in mean habitat area, with increasing habitat fragmentation followed by localized extinctions of the two species.     

Primers Designed for Amplification of Echinococcus multilocularis DNA Amplify the DNA of Encephalitozoon-Like Spores in the Polymerase Chain Reaction

ABSTRACT. Microsporidian spores were developed from cells which were grown in vitro from a human liver lesion which was due to larval Echinococcus multilocularis . The microsporidian spores developed in the same fashion as an Encephalitozoon cuniculi . The Encephalitozoon -like spores were completely separated on Percoll gradients. The separated spores contained DNA capable of amplification by two different primer sets designed for the polymerase chain reaction (PCR) of E. multilocularis DNA. However, the cell DNA from which microsporidium developed was thoroughly insensitive to the PCR using the E. multilocularis primer sets. The results strongly suggested that Encephalitozoon should be taken into consideration, when DNA isolated from larval E. multilocularis is analyzed.     

Potential fragmentation and loss of thermal habitats for charrs in the Japanese archipelago due to climatic warming

1. The upper thermal limits of the present distributions of two charr species, Dolly Varden, Salvelinus malma , and white-spotted charr, S. leucomaenis , in streams of the Japanese archipelago were examined using groundwater temperature as an index of thermal condition. The lower limits of the altitudinal distributions of Dolly Varden and white-spotted charr were delineated, respectively, by 8 and 16 °C groundwater isotherms.
2. The potential impact of future climatic warming on the geographical distribution, habitat extent and population fragmentation of each species was predicted at both the full archipelago and individual catchment levels.
3. For Dolly Varden, analysis at the full archipelago level indicated a loss of 27.6, 67.2, 79.6 and 89.6% of the current geographical range, respectively, for a 1, 2, 3 and 4 °C increase in mean annual air temperature. The present distribution area of white-spotted charr would likewise reduce by 4.1, 20.5, 33.8 and 45.6%, respectively.
4. Based on the analyses of three individual catchments, one for Dolly Varden and two for white-spotted charr, the lower habitat boundaries for the two charr species could be expected to rise increasingly to higher elevations in each catchment as warming proceeded. As a consequence, there would be large reductions in mean habitat area, with increasing habitat fragmentation followed by localized extinctions of the two species.     

A parallel geographical mosaic of morphological and behavioural aposematic traits of the newt, Cynops pyrrhogaster (Urodela: Salamandridae)

Aposematic animals advertise their unprofitability to potential predators with conspicuous coloration, occasionally in combination with other life-history traits. Theory posits that selection on functionally interrelated aposematic characters promotes the unidirectional evolution of these characters, resulting in an increase or decrease in the effectiveness of the signal. To test whether this prediction applies on a microevolutionary scale, the intra- and interpopulational variations in aposematic coloration, behaviour (which enhances the effectiveness of the coloration) and body size of newts, Cynops pyrrhogaster (Urodela: Salamandridae), were investigated. A parallel geographical mosaic of variation in aposematic coloration and behaviour among populations, independent of body size, was found. Newts on islands displayed more conspicuous aposematic traits than those on the mainland, both morphologically and behaviourally. There was no significant relationship between variation in coloration and behaviour within populations. Male newts displayed more conspicuous coloration than females. Surveys of potential predators suggest that variable natural selection at a local scale, such as predation pressure, may primarily be responsible for the microevolution of variable aposematic traits in newts.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 613–622.     

Impacts of light and temperature on shoot branching gradient and expression of strigolactone synthesis and signalling genes in rose

Light and temperature are two environmental factors that deeply affect bud outgrowth. However, little is known about their impact on the bud burst gradient along a stem and their interactions with the molecular mechanisms of bud burst control. We investigated this question in two acrotonic rose cultivars. We demonstrated that the darkening of distal buds or exposure to cold (5 °C) prior to transfer to mild temperatures (20 °C) both repress acrotony, allowing the burst of quiescent medial and proximal buds. We sequenced the strigolactone pathway MAX‐homologous genes in rose and studied their expression in buds and internodes along the stem. Only expressions of RwMAX1, RwMAX2 and RwMAX4 were detected. Darkening of the distal part of the shoot triggered a strong increase of RwMAX2 expression in darkened buds and bark‐phloem samples, whereas it suppressed the acropetal gradient of the expression of RwMAX1 observed in stems fully exposed to light. Cold treatment induced an acropetal gradient of expression of RwMAX1 in internodes and of RwMAX2 in buds along the stem. Our results suggest that the bud burst gradient along the stem cannot be explained by a gradient of expression of RwMAX genes but rather by their local level of expression at each individual position.     

Isolation of the Antheridiogen of Anemia phyllitidis

The antheridiogen (antheridium-inducing substance) of the fern species Anemia phyllitidis has been obtained in pure form based on the isolation procedure described below. Pure antheridiogen is active to a dilution of 10 μg/l in antheridium formation and 0.3 μg/l in dark-germination. Its molecular formula is C₁₉H₂₂O₅.     

ONTOGENY OF CHICKEN HEMOGLOBIN II. CHROMATOGRAPHIC STUDY OF THE HETEROGENEITY OF HEMOGLOBIN IN DEVELOPMENT

Some properties of the carbonmonoxyhemoglobin (HbCO) from chicken embryos of ages 5, 10 and 15 days of incubation, from 1-day posthatching and from adult chickens have been investigated by chromatography on carboxymethylcellulose (CM-cellulose) column and by starch gel electrophoresis.
Chromatogram of the hemoglobin (Hb) from 5-day chicken embryos has shown that it consists of at least 6 components. Starch gel electrophoresis of each isolated component from the column in phosphate (pH 6.8), in borate (pH 8.6) and in formate buffer (pH 1.9) has shown later that there are 3–4 embryonic type Hb components in 5-day embryos.
Chromatogram of the hemoglobin from adult chickens has shown that it consists of at least 4 components, but the examination of each isolated component from the column by electrophoresis in phosphate (pH 6.8), in borate (pH 8.6) and in formate buffer (pH 1.9) has shown that there are 4–6 adult type Hb components in adults.
In ontogenic process, embryonic Hb type is detectable in embryos up to 15 days of incubation. Fetal Hb type, which is not detectable in adult chickens, can be first found in 10-day embryos.     

GENERAL PATTERN, 35SO4-INCORPORATION AND INTRACELLULAR LOCALIZATION OF GLYCANS IN DEVELOPING SEA URCHIN (ANTHOCIDARIS) EMBRYOS

Glycosaminoglycan (GAG) prepared from sea urchin embryos ( Anthocidaris crassispina ) at various stages with or without pulse ³⁵SO₄-labelling was separated into various fractions by chromatography on DEAE-cellulose with a linear NaCl concentration gradient: fraction "P" (nonacidic) and fractions "A" through "F" (of increasing acidities). The ³⁵SO₄-radioactivity was negligible in "P" and "A", largest in "B" and "C", and decreased in the other fractions three alphabetical order. During development (hatched blastulae to gastrulae) the glycans in fractions "P" and "A" decreased in amount, whereas those in "E" and "F" increased. "E" contained heparin-like (AMPS-1) and dermatanpolysulfate-like (AMPS-2) GAG in addition to a sulfated fucogalactan-like (E₁) glycan. Another sulfated fucogalactan-like (F₁) glycan was found in "F". A sulfated polysialic acid-like (S₁) glycan was found in "C". An EDTA-extract of gastrulae gave AMPS-2, E₁ and F₁. The mitochondria-rich fraction gave AMPS-1, whereas the yolk granule-rich fraction gave S₁. Most of the other still unidentified components in "B", "C", and "D" appeared to be derived from glycoproteins and were mainly located in the crude yolk-mitochondrial and cytosol fractions.