Meiotic studies ofElymus nutans andE. jacquemontii (Poaceae,Triticeae) and their hybrids withPseudoroegneria spicata and seventeenElymus species

Hybridizations ofElymus nutans andE. jacquemontii were carried out with one species ofPseudoroegneria (S genome), and 20Elymus species, each containing either of the SH, SY, SYH, or SYW genomes. Chromosome configurations were analysed at metaphase I of the two target taxa and their interspecific hybrids. It is concluded that (i)E. nutans is an allohexaploid containing the SYH genomes, andE. jacquemontii is an allotetraploid having the SY genomes; (ii) the genomic affinity is associated with the geographic distance between the species studied; (iii) minor genomic structural rearrangements have occurred within the hexaploid taxon ofE. nutans.     

Polymorphism of the HLA DR1 haplotype in the Israeli population investigated at the serological,cellular, and genomic levels

In the present report, we used serological, cellular, and restriction fragment length polymorphism (RFLP) to investigate the DR1 haplotype in the Israeli population. We describe an Israeli homozygous typing cell (HTC), HLA-DwLVA, which defines a new lymphocyte-activating determinant associated with Bw65, DR1 and distinct from Dwl. The parents of this donor, non-Ashkenazi Algerian Jews, are first cousins and share HLA-Cw8, Bw65, BfS, DR1, DQw1, DPw4. No specificity could be assigned to HLA-DwLVA using the 91 Ninth Workshop HTCs. Two families and forty unrelated DR1 individuals were studied with DwLVA and a panel of DR1/Dw1 HTCs. HLA-DwLVA showed segregation as a single determinant within families. This new specificity was present in 24 out of 40 (60%) unrelated DR1 individuals, indicating that in the Israeli population DwLVA is the main lymphocyte-defined determinant associated with the serologically defined DRI specificity, in contrast to non-Jewish Caucasoids where DR1 is significantly associated with Dw1. The vast majority of DwLVA-positive carriers were also Bw65 carriers, indicating that Bw65, DR1, DwLVA may represent a typical allele combination in the Israeli population. The RFLP analysis established the correlation of certain RFLPs with Dw1 and DwLVA. In addition, we describe a cluster of RFLPs that may correspond to a new Dw subtype associated with DR1, for which no serological and cellular reagents have been described so far.     

Observations on the fine structure of the cercaria of Notocotylus attenuatus and formation of the cyst wall of the metacercaria

Summary The dorsal tegument of the mature cercaria of Notocotylus attenuatus is a syncytial, cytoplasmic layer, containing two types of secretory granule which are identifiable ultrastructurally. The type 1 secretory bodies are electron lucid, whereas most type 2 granules have a banded appearance. The ventral tegument contains granules which are secreted from the type 3 cells; the type 3 granules are membrane bound, electron dense, and consist of both an amorphous and a finely striated zone. The type 4 cells mainly contain cigar-shaped granules consisting of an amorphous core surrounded by concentric striations. The granules exhibit structural variability in shape and content. The type 4 cells undergo a cellular migration to the tegument during encystment. The structure of the posterior-lateral glands and mode of secretion of the granules are described. Possible functions of microtubules are discussed for each cell type. Details of some secretory processes involved in the formation of the hemispherical cyst wall are described. The layers of the cyst wall may be related to the granular contents of the various parenchymal cells of the cercaria. The tegument of the metacercaria originates primarily from the cytoplasm of the type 1, type 2, type 3 and type 4 cells.     

The rapid switch-off of nitrogenase activity in obligate methane-oxidizing bacteria

Nitrogenase activity in the obligate methaneoxidizing bacterium Methylococcus capsulatus (Bath) was added ammonia. This observation was extended to include other ammonia. This observation was extended to include other representative N₂-fixing species of methanotrophs. The ammonia switch-off of nitrogenase in M. capsulatus (Bath) was reversed on washing cells to remove excess ammonia, in the presence of chloramphenicol, suggesting that a form of covalent modification of nitrogenase may occur. Replacing the oxidizable substrate methanol with formaldehyde, formate, ethanol or hydrogen had no effect on nitrogenase switch-off. A number of potential nitrogen sources or intermediates of nitrogen metabolism such as glutamine, asparagine, glutamate and alanine when tested, did not effect switch-off. However, the rapid inhibition of nitrogenase activity of M. capsulatus (Bath) could be achieved by adding the uncoupler carbonylcyanide m-chlorophenylhydrazone or nitrite. The glutamine synthetase inhibitor methionine sulphoximine blocked the switch-off effect of ammonia, indicating that the metabolism of ammonia may be essential for switch-off to occur. Inhibitors of glutamate synthase did not alleviate the ammonia switch-off response. Methionine sulphoximine did not alleviate the rapid inhibition of nitrogenase by carbonylcyanide m-chlorophenylhydrazone indicating that the shortterm regulation of nitrogenase by uncouplers and ammonia proceed via different mechanisms.Abbreviations MSX methionine-DL-sulphoximine - DON 6-diazo-5-oxo-L-norleucine - GS glutamine synthetase - GOGAT glutamine 2-oxoglutarate aminotransferase (glutamate synthase) - CCCP carbonylcyanide m-chlorophenyl hydrazone     

Polygonal inequalities as a key to neuronic equations

Neuronic or decision equations, first proposed as a mathematical model of neural activity, have shown, after their exact, compact solution was found, typical behaviours that make them natural tools for General Systems studies. It is shown here that their mathematical investigation is remarkably furthered by generalizing the triangular inequality to polygonal ones. These permit the immediate computation of the tensorial expansion of linearly separable boolean functions, and exhibit clearly the connection between their continuous and discontinuous aspects.     

Einige Bemerkungen über die Ersatzgeschlechtstiere vonReticulitermes

Zusammenfassung An Laboratoriumszuchten vonReticulitermes lucifugus Rossi undReticulitermes flavipes Kollar (aus den Hamburger Befallsgebieten) werden Beobachtungen zur Biologie der Ersatzgeschlechtstiere mitgeteilt. Für die Durchführung dieser Beobachtungen wurden besondere Schaunester eingerichtet. Folgende Punkte der beobachteten Verhaltensweisen werden hier hervorgehoben: Die Nymphen der Ersatzgeschlechtstiere sammeln sich stets in Herden von 80–100 Einzeltieren und werden von einer Gruppe Arbeiter (als Hütehunde) bewacht. Die Arbeiter halten die Nymphen auf einem engen Raum zusammen und versuchen andere Nestgenossen von den Nymphen fernzuhalten. Alle ein bis zwei Tage wechseln die Herden ihren Standort. Das Weiterziehen geschieht gleichfalls in Form von Herden.Die Ernährung der Nymphen geschieht auf stomodealem Wege durch die Arbeiter. *** DIRECT SUPPORT *** A0180089 00007     

Histochemical studies on the distribution of β-glucuronidase and succinic dehydrogenase in young and old spinal ganglion cells of the rat

Summary The present study compares the distribution of -glucuronidase and succinic dehydrogenase in young and old spinal ganglion cells of rat. In young cells there are indications of cyclic activity of these enzymes, i.e., in some stages there are perinuclear concentrations of the enzymes, at other times -glucuronidase and succinic dehydrogenase are uniformly distributed throughout the cytoplasm. These stages have been discussed with the identical distribution of mitochondria. However, in old spinal ganglion cells both -glucuronidase and succinic dehydrogenase become mainly concentrated in the pigment areas, suggesting thereby their possible role in the production of pigment, through the medium of the mitochondria.     

Studies on aneuploids of Petunia

Summary The seven possible primary trisomics of Petunia (2 n= 14) located in the progenies of triploid, hypertriploid and hypotriploid plants were distinguished from one another and from diploid on the basis of cytological and morphological criteria. They were provisionally named as Oval, Semi, Slender, Pseudonormal, Arrow, Narrow and Giant. In three of the trisomics, the extra chromosome was identified for the first time at pachytene stage. Postpachytene studies revealed no precise relationship between the length of extra chromosome and the frequency of multiple association.     

A comparison of male and female recombination frequency in wheat using RFLP maps of homoeologous group 6 and 7 chromosomes

A novel approach was used to compare male and female recombination rates in wheat. Doubled haploid lines were developed from an F₁ using two distinct approaches: the anther-culture technique and the Hordeum bulbosum system, from which sets of lines were developed from male and female meioses, respectively. The genotype of the lines was established at RFLP and isozyme markers polymorphic on chromosomes of homoeologous groups 6 and 7, and male and female linkage maps were calculated using this information. The markers in one segment of chromosome 6B exhibited disturbed segregation frequencies in the anther-culture population. The male and female maps differed significantly in recombination frequency between some markers on two chromosomes, and these were consistent in direction within chromosomes and inconsistent in direction between chromosomes. In two of the four chromosomes studied the male map was much longer than the female map. These results suggest that significant differences may exist in male and female recombination frequencies in bread wheat which are specific to certain chromosomal segments but are inconsistent in direction between chromosomes. Other factors, such as environmental influences, may also be important in creating differences.     

Cytological analysis on the distribution and origin of the alien chromosome pair conferring blue aleurone color in several European common wheat (Triticum aestivum L.) strains

Summary Meiotic chromosome pairing and Giemsa C-banding analyses in crosses of several European blue-grained wheat strains with Chinese Spring double ditelosomic and other aneuploid lines showed that Triticum aestivum Blaukorn strains Berlin, Probstdorf, Tschermak, and Weihenstephan are chromosome substitutions, in which the complete wheat chromosome 4A pair is replaced, whereas the strains Brünn and Moskau are 4B substitutions. The alien chromosome pair in all of these strains is an A genome chromosome (4A) from diploid Triticum monococcum or T. boeoticum not present in common tetraploid and hexaploid cultivated wheats. The Blaukorn strain Weihenstephan W 70a86 possesses, in addition to a rye chromosome pair 5R compensating for the loss of part of chromosome 5D, a 4A/5DL translocation replacing chromosome pair 4B of wheat.     

Charles Darwin's theory of evolution: A review of our present understanding

The paper characterizes Darwin's theory, providing a synthesis of recent historical investigations in this area. Darwin's reading of Malthus led him to appreciate the importance of population pressures, and subsequently of natural selection, with the help of the wedge metaphor. But, in itself, natural selection did not furnish an adequate account of the origin of species, for which a principle of divergence was needed. Initially, Darwin attributed this to geographical isolation, but later, following his work on barnacles which underscored the significance of variation, and arising from his work on botanical arithmetic, he supposed that diversity allowed more places to be occupied in a given region. So isolation was not regarded as essential. Large regions with intense competition, and with ample variation spread by blending, would facilitate speciation. The notion of place was different from niche, and it is questioned whether Darwin's views on ecology were as modern as is commonly supposed. Two notions of struggle are found in Darwin's theory; and three notions of variation. Criticisms of his theory led him to emphasize the importance of variation over a range of forms. Hence the theory was populational rather than typological. The theory required a Lamarckian notion of inheritable changes initiated by the environment as a source of variation. Also, Darwin deployed a use/habit theory; and the notion of sexual selection. Selection normally acted at the level of the individual, though kin selection was possible. Group selection was hinted at for man. Darwin's thinking (and also the exposition of his theory) was generally guided by the domestic-organism analogy, which satisfied his methodological requirement of a vera causa principle.     

Mutants of Arabidopsis thaliana with altered phototropism

Thirty five strains of Arabidopsis thaliana (L.) Heynh. have been identified with altered phototropic responses to 450-nm light. Four of these mutants have been more thoroughly characterized. Strain JK224 shows normal gravitropism and second positive phototropism. However, while the amplitude for first positive phototropism is the same as that in the wild-type, the threshold and fluence for the maximum response in first positive phototropism are shifted to higher fluence by a factor of 20–30. This mutant may represent an alteration in the photoreceptor pigment for phototropism. Strain JK218 exhibits no curvature to light at any fluence from 1 mol·m^-2 to 2700 mol·m^-2, but shows normal gravitropism. Strain JK345 shows no first positive phototropism, and reduced gravitropism and second positive phototropism. Strain JK229 shows no measurable first positive phototropism, but normal gravitropism and second positive phototropism. Based on these data, it is suggested that: 1. gravitropism and phototropism contain at least one common element; 2. first positive and second positive phototropism contain at least one common element; and 3. first positive phototropism can be substantially altered without any apparent alteration of second positive phototropism.Abbreviation WT wild-type     

Polymorphism and Mendelian inheritance of photosystem II 23-kilodalton polypeptide

Soluble proteins from leaves of Nicotiana glauca Grah., N. langsdorffii Weinm., their reciprocal hybrids and amphiploid hybrid (N. glaucaxN. langsdorffii) were resolved by two-dimensional gel electrophoresis. Among a group of well-resolved polypeptides, in the isoelectric-point range of 5–5.5 and relative-molecular-mass (M_r) range of 18–23 kilodaltons (kDa), species-specific variation was observed. Polypeptides designated L and l are specific to N. langsdorffii, and G and g to N. glauca, while C is common to both species. Polypeptides L, G and C are localized in the chloroplasts and associated with thylakoid membranes. Polypeptide L is more acidic than polypeptide G, and both polypeptides have an M_r of 23 kDa. They were isolated from two-dimensional gels and their first 13 N-terminal amino-acid sequences were determined. These were found to be identical to the 13N-terminal amino acids of the photosystem II (PSII) 23-kDa polypeptide from spinach (T. Jansen et al. (1987) FEBS Lett. 216, 234–240) and, except for one change, to those from pea (R. Wales et al. (1989) Plant Molec. Biol., in press). Polypeptides G and L cross-react with antiserum against the PSII 23-kDa polypeptide from pea. Therefore, polypeptides G and L are extrinsic PSII 23-kDa polypeptides. They appear jointly and in equal amounts in the reciprocal hybrids. Since chloroplasts in Nicotiana are maternally inherited, these results demonstrate that polypeptides G and L are encoded by nuclear genes, are polymorphic variants of the PSII 23-kDa polypeptide, and are inherited in a Mendelian manner.Abbreviations kDa kilodalton - LS large subunit of Rubisco - M_r relative molecular mass - NEPHGE non-equilibrium pH gradient gel electrophoresis - PSII photosystem II - Rubisco ribulose-1,5-bisphosphate carboxylase/oxygenase - SDS-PAGE sodium dodecyl sulfate polyacrylamide gel electrophoresis - SS small subunit of Rubisco     

The hypothalamo-hypophysial system in acipenseridae

Summary The neurohypophysis of sexually mature male and female Acipenser güldenstädti Brandt and Acipenser stellatus Pallas was studied light and electron microscopically. The recessus hypophysei lined with ependymal cells of two main types, narrow and wide, are in the center of the neurohypophysial roots. Processes from both cell types run radially to the basement membrane of the connective tissue layers abutting on the hypophysial intermediate lobe. Protrusions penetrating deep into the recessus hypophyseus are found in the apical parts of the wide cells. Pituicytes are rare in the neurohypophysis. The ultrastructure of both ependymal cell types and of the pituicytes is described. Nonmyelinated Gomori-positive (peptidergic) neurosecretory A₁ and A₂ type fibres and their terminals containing elementary neurosecretory granules (1400–1800 Å and 1000–1400 Å respectively) are the main structural elements of the neurohypophysis. Some dark and single myelinated neurosecretory fibres have been found. The adrenergic fibres (type B) were described earlier (Polenov et al., 1972a). The structural peculiarities of the neurohypophysis are discussed in functional and comparative-morphological terms.     

Induction,polarity and spatial control of cytokinesis in some abnormal subsidiary cell mother cells ofZea mays

Summary Cytokinesis in the subsidiary cell mother cells (SMCs) ofZea mays leaves grown in the presence of 5 mM of caffeine solution is usually partially inhibited. A continuous wall strip, resembling a portion of the subsidiary cell (SC) wall, is laid down in the preprophase microtubule band (PMB) cortical zone. Sometimes, the incomplete SC (SC) wall grows centripetally in the absence of a phragmoplast and the gap becomes smaller or closes. The SC nucleus escapes through the SC wall gap into the larger SMC compartment and may fuse with the other nucleus.The aberrant SMCs (a-SMCs) pass through another division cycle, reattempting to produce a SC. A typical PMB is found in the SC space, in the site of the previous PMB. Moreover, in some preprophase SMCs, the cytoplasm adjacent to the SC wall is traversed by a small number of microtubules. The preprophase nuclei are partly or totally separated from the PMB by the perforated SC wall and may lie far from the latter.Usually, one mitotic spindle is assembled. The cycling paired polarized nuclei appear to synchronize and their chromosomes line up together on a single metaphase plate. Although the mitotic spindle axis is diversely oriented, one of its poles tends to be stabilized in the proximity of the SC wall gap. These divisions separate abnormal cells. Most or all the cell plate edges fuse with wall regions far from the PMB cortical zone. However, when some of them approach the SC wall strips, they are attracted and intersect their rims. In rare occasions the cell plate, invading the SC space is guided by the PMB cortical zone to create a SC-like curved wall portion, in absence of a daughter nucleus.Observations show that the cell plate arrangement in redividing aberrant SMCs is not subjected to a strict spatial control. The disorder of polarization sequence generated by the SC wall ring and especially the perturbation of the spatial (and functional?) relationship between PMB-PMB cortical zone and the nucleus—mitotic spindle is a causal factor of the variable cell plate arrangements.     

Screening of white-rot fungi for biological pretreatment of wheat straw for biogas production

Summary Twenty two basidiomycetes, mostly white rot fungi, were grown on wheat straw. Lignin-, cellulose-, and hemicellulose-degradation was recorded in order to find a species growing on lignin preferably. The oyster-mushroomPleurotus sp. florida showed fastest delignification of all tested fungi.Straw pretreated by this fungus was fermented anaerobically to biogas. The gas yield produced from myco-straw is twice the amount from untreated straw.     

Saponin-like substances inhibit α-galactosidase production in the endosperm of fenugreek seeds

When fenugreek (Trigonella foenum-graecum L.) endosperms plus testa (endosperms), which had been isolated from 5-h-imbibed seeds, were incubated for at least 2 h under germination conditions, they leaked substances which, like exogenous abscisic acid (ABA), inhibited the production of fenugreek endosperm -galactosidase. However, unlike ABA, 8 h treatment with these inhibitors had no effect on fenugreek endosperms which had been isolated from 15-h-imbibed seeds and leached for 2 h. This indicated that either their inhibitory action was on processes which were related to the production of -galactosidase and had been completed by this time, or that there might be factors present which inactivate these inhibitors. It was also concluded that the action of the endosperm leachate could not be attributed to the presence of ABA. The activity of the leachate decreased when it originated from endosperms imbibed for periods longer than 25 h and thin-layer chromatography (TLC) of extracts from these endosperms showed decreased contents of the leachable inhibitors as imbibition proceeded. From the seed leachate, which had a TLC pattern and inhibitory action similar to that of the endosperm, were isolated three substances which, when applied to endosperms, inhibited the production of -galactosidase activity. According to their chromatographic behaviour and their reaction with specific reagents, there are strong indications that these substances are saponins. These diffusible saponin-like substances were located in both endosperm and perisperm and their physiological role is discussed.Abbreviations ABA abscisic acid - PEG polyethylenglycol - TLC thin-layer chromatography We wish to thank the Alexander S. Onasis Public Benefit Foundation for a grant to K.Z. and Dr. J.S.G. Reid (University of Stirling, Scotland) for a kind gift of fenugreek seeds.     

The mitochondrially encoded "phantom ATPase" of S. cerevisiae. II. A heterogeneous mitochondrial ATPase population in situ.

Summary The mitochondrial ATPase from a PHO 1 mutant (OLI 2, PHO 1, OLI 4 region on mit DNA of S. cerevisiae) was further examined. A new purification method using Lysolecithin instead of Triton allowed us to solubilize and separate a heterogeneous ATPase population from PHO 1-mitochondria: the major abnormal fraction had extremely low oligomycin-sensitivity (but normal specific immunological reactivity), while a minor normal fraction (representing about 20% of the initial mitochondrial ATPase activity) had high sensitivity and affinity for oligomycin.Moderate urea treatment of PHO 1-mitochondria leads to partial loss of ATPase activity and a concomitant increase of oligomycin-sensitivity, suggesting that a heterogeneous ATPase population exists in situ in the mitochondrial membrane: part of the major abnormal ATPase fraction is selectively inactivated by urea, producing a concomitant enrichment in the initially minor normal ATPase fraction.If the minor normal ATPase fraction is the only one capable of in vivo ATP synthesis, the deficient but oligomycin-sensitive cell growth and oxidative phosphorylation in vitro are readily explained.Further structural studies are under way to ascertain whether the minor normal ATPase fraction is strictly identical to the wild type, in which case PHO 1 is a regulatory gene, or not, in which case PHO 1 is a structural gene.     

Evaluation of microbial testing methods for the mutagenicity of quinoline and its derivatives

Using the mutational enhancement method and the Ames test, the mutagenicity and potential carcinogenicity of quinoline and its derivatives were determined and compared. Quinoline, 8-hydroxyquinoline, 5-hydroxyquinoline, 8-hydroxyquinoline sulfate, 6-nitroquinoline, 8-nitroquinoline, and 3-methylquinoline were mutagenic in the Ames direct plating test on TA 98 and TA 100 with activating system (S-9) from the rat liver. These compounds were not mutagenic in the mutational enchancement test onEscherichia coli HCR+ strain. 5,7-Dichloro-8-hydroxyquinoline, isoquinoline, and 2-chloroquinoline were nonmutagenic without or with S-9 in both the Ames and mutational enhancement test system. The compounds chloroquine, primaquine diphosphate, quinine hydrobromide, quinine hydrochloride, quinine lactate, quinine urea hydrochloride, quinine ethylcarbonate, quinine dihydrochloride, beta quinine quinine valerate, and quinine glycerophosphate were nonmutagenic with and without S-9 in the Ames test but mutagenic (20–60 g/ml) in the mutational enhancement test method onEscherichia coli HCR+ strains. The observations reported here point out that the Ames test responds negatively to several quinoline derivatives that are positive in the mutational enchancement test method.     

Pancreatic glucagon cells contain endorphin-like immunoreactivity

Summary On the basis of the histochemical activity of succinic dehydrogenase, only two fibre-types are distinguished in pigeon pectoralis major muscle. These are narrow Red and broad White. The histochemical activity of myofibrillar ATPase was studied in these two distinct fibre-types. Both fibre-types showed high activity for the ATPase. Red fibres of pigeon pectoralis were not alkali-labile, at incubation pH 9.4, as were the Type I fibres of both avian and mammalian muscles. Again unlike Type I fibres, the Red fibres of pigeon pectoralis lacked the characteristic activation of acid-preincubated ATPase reaction. Pigeon pectoralis Red fibres are known to posses some characteristics of fast-twitch fibres (e.g. high fat, considerable phosphorylase, fibrillenstruktur myofibrillar arrangement, focal en plaque pattern of nerve endings). It is emphasized, therefore, that the pigeon pectoralis Red fibres are not equivalent to Type I or slow-twitch, muscle fibres, but they are possibly fast-twitch fatigue resistent or Type II Red muscle fibres.