Radiation induced formation of giant cells inSaccharomyces uvarum III: Effect of X-rays on nuclear division

Summary Spindle formation and nuclear division of budding and irradiated yeast cells (Saccharomyces uvarum) was investigated by fluorescence microscopy of protoplasted cells. Protoplasts were treated with antitubulin antibodies and DAPI, a fluorescent dye staining DNA. In budding yeast cells, duplication of spindle pole bodies as well as formation of complete 1-µm spindles and elongated 8-µm spindles were documented. In X-irradiated cells, spindle pole bodies were duplicated as well, forming the complete 1-µm spindle. Nuclei of giant cells have lost the elongation ability and remain in a normal G₂-phase state, thus preventing nuclear as well as cellular division.     

Characterization of a cDNA clone for the nonspecific cross-reacting antigen (NCA) and a comparison of NCA and carcinoembryonic antigen

NCA (nonspecific cross-reacting antigen), a glycoprotein found in normal lung and spleen, is immunologically related to carcinoembryonic antigen (CEA), which is found in over 95% of colon adenocarcinomas. From a human genomic library, we previously cloned part of an NCA gene and showed that the amino-terminal region has extensive sequence homology to CEA (Thompson, J. A., Pande, H., Paxton, R. J., Shively, L., Padma, A., Simmer, R. L., Todd, Ch. W., Riggs, A. D., and Shively, J.E. (1987) Proc. Natl. Acad. Sci. U. S.A. 84, 2965-2969). We now present the nucleotide sequence of a cDNA clone, containing the entire coding region of NCA (clone 9). The clone was obtained from a lambda gt 10 library made from the colon carcinoma cell line SW 403; the clone contains a 34-amino acid leader sequence, 310 amino acids for the mature protein, and 1.4 kilobases of 3'-untranslated region of the NCA gene. A comparison of the NCA sequence to the CEA sequence (Oikawa, S., Nakazato, H., and Kosaki, G. (1987) Biochem. Biophys. Res. Commun. 142, 511-518; Zimmerman, W., Ortlieb, B., Friedrich, R., and von Kleist, S. (1987) Proc. Natl. Acad. Sci. U. S. A. 84, 2690-2694) shows that both proteins contain doublets of an immunoglobulin-like domain, of which there are one copy in NCA and three copies in CEA, a 108-amino acid amino-terminal domain with no cysteine residues, and a carboxyl-terminal hydrophobic domain of sufficient length to anchor the glycoproteins in the cell membrane. Overall, the corresponding coding regions possess 85% sequence homology at the amino acid level and 90% homology at the nucleotide level. Forty nucleotides 3' of their stop codons, the CEA and NCA cDNAs become dissimilar. The 108-amino acid amino-terminal region together with part of the leader peptide sequence corresponds exactly to a single exon described in our previous work. The data presented here further demonstrate the likelihood that CEA recently evolved from NCA by gene duplication, including two duplications of the immunoglobulin-like domain doublet of NCA.     

Performance of two Picea abies (L.) Karst. stands at different stages of decline

Summary Photosynthetic rates and nutrient contents of spruce needles were measured in a region with high levels of air pollution in NE Bavaria, Germany (FRG), and compared to spruce grown under clean air conditions at Craigieburn, in the South Island of New Zealand (NZ). The absolute rates of CO₂ uptake, the slope of the CO₂ response curve at 240 l l^–1 internal CO₂ concentration, and the change of photosynthetic rates with needle age at ambient and saturated CO₂ concentrations were virtually identical at both measuring sites. These results confirm an earlier conclusion, that there is no long-term effect of atmospheric pollutants directly on photosynthetic CO₂ uptake rates with persistent exposure at the FRG site to high levels of anthropogenic air pollution. Photosynthetic capacity at saturating CO₂ concentration was three times higher in the NZ spruce. Needles with high photosynthetic capacity in NZ had lower nitrogen and higher calcium concentrations per unit dry weight but higher concentrations of nitrogen, phosphorus, potassium, magnesium and calcium per unit leaf area, and twice the specific leaf weight.     

Multiple domains of the large fibroblast proteoglycan, versican.

The primary structure of a large chondroitin sulfate proteoglycan expressed by human fibroblasts has been determined. Overlapping cDNA clones code for the entire 2389 amino acid long core protein and the 20-residue signal peptide. The sequence predicts a potential hyaluronic acid-binding domain in the amino-terminal portion. This domain contains sequences virtually identical to partial peptide sequences from a glial hyaluronate-binding protein. Putative glycosaminoglycan attachment sites are located in the middle of the protein. The carboxy-terminal portion includes two epidermal growth factor (EGF)-like repeats, a lectin-like sequence and a complement regulatory protein-like domain. The same set of binding elements has also been identified in a new class of cell adhesion molecules. Amino- and carboxy-terminal portions of the fibroblast core protein are closely related to the core protein of a large chondroitin sulfate proteoglycan of chondrosarcoma cells. However, the glycosaminoglycan attachment regions in the middle of the core proteins are different and only the fibroblast core protein contains EGF-like repeats. Based on the similarities of its domains with various binding elements of other proteins, we suggest that the large fibroblast proteoglycan, herein referred to as versican, may function in cell recognition, possibly by connecting extracellular matrix components and cell surface glycoproteins.     

Direct genomic fluorescent on-line sequencing and analysis using in vitro amplification of DNA.

In vitro amplification of genomic DNA and total RNA, as well as recombinant DNA, using one fluorescently labelled and one unlabelled primer during amplification, together with on-line analysis of the products on the EMBL fluorescent DNA sequencer, is described. Further is reported direct sequencing of fluorescently labelled amplified probes by solid-phase chemical degradation, without subcloning and purification steps involved. At present up to 350 bases in 4 hours are determined with this technique. The fluorescent dye and its bond to the oligonucleotide are stable during the amplification cycles, and do not interfere with the enzymatic polymerization. High sensitivity of the detection device, down to 10(-18) moles, corresponding to less than 10(6) molecules makes possible analyses of the non-radioactive amplified probes after only 10 amplification cycles, starting with about 5 x 10(4) copies of recombinant DNA.     

Characterization and Serological Detection of Four Closterovirus-like Particles Associated with Leafroll Disease on Grapevine

Four serologically unrelated closterovirus-like particles (GLRV-1, GLRV-2, GLRV-3 and GLRV-4) were isolated in our laboratory from leafroll diseased grapevines. Polyclonal antibodies raised against these particles were useful for their characterization and their detection in infected plants. The coat proteins of these four serotypes were characterized by a SDS-PAGE after denaturation, followed by a transfer on nitrocellulose sheet and immunoprinting using the specific polyclonal antibodies. The capsid of GLRV-1, GLRV-2, GLRV-3 and GLRV-4 contains a single protein species with molecular weight of about 39 Kd, 26 Kd, 43 Kd and 36 Kd respectively. No serological relation was found between these four filamentous particles either by ELISA, immuno electron microscopy or immunoblotting experiments. Serological analysis of many grapevines originating from the Middle East and Europe showed a very close association between the presence of GLRV-1, GLRV-2, GLRV-3 and GLRV-4 antigens, and leafroll symptoms on Vitis vinifera Pinot Noir. This association was confirmed by testing symptomless and diseased grapevines collected in the field, and by serological analysis of heat treated plants originally infected by GLRV-1 and GLRV-3, which are the most widespread antigens detected in leafroll infected grapevines.     

New results of the “EPOS” leg 3 cruise to antarctica: Horizontal and vertical distribution of isopods (Crustacea) in the eastern Weddell Sea

Summary A comparison of the EPOS leg 3 material of Weddell Sea Isopoda with the known literature data revealed some new results for the horizontal and vertical distribution of isopods in the eastern Weddell Sea. The number of isopod species known for the Weddell Sea almost doubled to 118 species. New results on the vertical distribution of 11 isopod genera are presented.Data presented here were collected during the European Polarstern Study (EPOS) sponsored by the European Science Foundation     

Identification of extracellular proteins from actinomycetes responsible for the solubilisation of lignocellulose

Summary We have utilized strains of three actinomycete species, Actinomadura sp, Streptomyces cyaneus and Thermomonospora mesophila, to study the solubilisation of lignocellulose. The production of extracellular proteins, was measured for each of the organisms during 17 days growth using medium containing either glucose or ball-milled straw. Some of the extracellular proteins (as identified by SDS gel electrophoresis) were present under both growth conditions, but others were specific to the type of medium or the period of incubation. The levels of proteins were compared with the abilities of the extracellular protein preparations to solubilise a substrate of ¹⁴C-labelled lignocellulose. About 6% of the radioactive material were solubilised when the extracellular proteins from the cultures grown on glucose were incubated with the substrate, compared to 20–30% that were solubilised by the extracellular proteins from the cultures grown on ball-milled straw. Partial characterisation of an enzyme from S. cyaneus responsible for the solubilisation of lignocellulose was achieved by gel filtration of the extracellular proteins, using Superose 12. Material that eluted from the column with an apparent molecular weight of about 20 000 accounted for all of the solubilisation of ¹⁴C-labelled (i.e. lignin-derived) moieties. In contrast, when the eluate was tested for the presence of cellulases and xylanases most of the activities were found in fractions containing material with an apparent molecular weight of about 45 000. We conclude that in cultures of S. cyaneus grown on ball-milled straw, a single extracellular enzyme is responsible for the solubilisation of lignin in lignocellulose, and that this enzyme is unlikely to be a cellulase or a xylanase.