Identification of foreign gene sequences by transcript filtering against the human genome.

We have developed a computational subtraction approach to detect microbial causes for putative infectious diseases by filtering a set of human tissue-derived sequences against the human genome. We demonstrate the potential of this method by identifying sequences from known pathogens in established expressed-sequence tag libraries.     

Electrophoresis of isoenzymes of 16 western shrubs: technique development

Wildland shrubs have gained considerable attention in recent years due to increasing recognition of their values as animal feed, as wildlife habitat, and for land reclamation. Better management of the shrub resource will be possible through clearer taxonomic identification and better understanding of phylogenetic relationships. This study applied polyacrylamide gel electrophoresis and further developed this technique to address genetic relationships among 16 paired shrub species (genera: Artemisia, Chrysothamnus, Atriplex, Ceratoides, Sarcobatus, Purshia, Cowania, and Cercocarpus [Compositae, Chenopodiaceae, Rosaceae]). Cluster analysis of similarity values for total protein and 14 isoenzyme systems gave patterns of species relationships expected from classical morphological grounds with two minor exceptions. Isoenzyme analyses showed promise for solving taxonomic, phylogenetic, and population genetics problems.     

Effect of salinity and planting density on physiological responses of Allenrolfea occidentalis

Physiological responses of Allenrolfea occidentalis to salinity and seedling density were investigated. Effects of salinity (0, 200, 400, 600, 800, and 1000 mM NaCl) and 3 planting densities (2000, 4000, 6000 plants m -2 ) on the growth, survival, and ecophysiology of A. occidentalis , a stem succulent inland halophyte, were studied under controlled greenhouse conditions. Plants were grown in a sand culture using subirrigation. Dry mass of roots was highest at 600 mM NaCl at low density (2000 plants m -2 ), but declined as salinity increased. Tissue water content was highest at the 200 mM NaCl treatment and decreased with increased salinity. Water potential of the plants became more negative with increasing salinity due to the accumulation of NaCl in the leaves. Inorganic ions, especially Na + and Cl - , contributed substantially to dry mass. Na + and Cl - concentration in shoots and roots increased when NaCl level was increased while K + , Ca ++ , Mg ++ , SO 4 -- , and NO 3 - contents decreased. Net photosynthesis increased at low salinity (200 mM), but photosynthesis at other salinities was not significantly different from the control. While A. occidentalis is very salt tolerant and photosynthesis functioned reasonably well at high salinities, extremely high salinity did decrease dry mass of roots and shoots.     

COT drives resistance to RAF inhibition through MAP kinase pathway reactivation

Oncogenic mutations in the serine/threonine kinase B-RAF (also known as BRAF) are found in 50-70% of malignant melanomas. Pre-clinical studies have demonstrated that the B-RAF(V600E) mutation predicts a dependency on the mitogen-activated protein kinase (MAPK) signalling cascade in melanoma-an observation that has been validated by the success of RAF and MEK inhibitors in clinical trials. However, clinical responses to targeted anticancer therapeutics are frequently confounded by de novo or acquired resistance. Identification of resistance mechanisms in a manner that elucidates alternative 'druggable' targets may inform effective long-term treatment strategies. Here we expressed ～600 kinase and kinase-related open reading frames (ORFs) in parallel to interrogate resistance to a selective RAF kinase inhibitor. We identified MAP3K8 (the gene encoding COT/Tpl2) as a MAPK pathway agonist that drives resistance to RAF inhibition in B-RAF(V600E) cell lines. COT activates ERK primarily through MEK-dependent mechanisms that do not require RAF signalling. Moreover, COT expression is associated with de novo resistance in B-RAF(V600E) cultured cell lines and acquired resistance in melanoma cells and tissue obtained from relapsing patients following treatment with MEK or RAF inhibitors. We further identify combinatorial MAPK pathway inhibition or targeting of COT kinase activity as possible therapeutic strategies for reducing MAPK pathway activation in this setting. Together, these results provide new insights into resistance mechanisms involving the MAPK pathway and articulate an integrative approach through which high-throughput functional screens may inform the development of novel therapeutic strategies.     

Kinetics of the reaction of kidney-bean leucoagglutinin with human lymphocytes

Zusammenfassung Es wurde die Kinetik der Reaktion zwischen Lymphozyten und Leukoagglutinin ausPhaseolus vulgaris untersucht.

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Supported by grants from the Sigrid Jusélius Foundation, The Finska Läkaresällskapet and the Finnish Medical Research Council.