Distance between south-European and south-west Asiatic refugial areas involved morphological differentiation: Pinus sylvestris case study

16 p., mapas, tablas, gráf.The phenotypic differentiation of relic P. sylvestris in southern Europe and southwestern Asia was verified using thirty-two populations sampled from the Iberian Peninsula, Massif Central, Balkan Peninsula, Crimea and Anatolia. Twenty-one morphological and anatomical needle traits and 18 cone morphological characteristics were examined to describe the population diversity and differentiation. The needle characters were not correlated to those of cone. The differences between regions were significant based on 12 needle and 9 cone characteristics, suggesting spatial isolation. The differentiation between the Iberian and Anatolian populations was the highest, which indicates the isolation by distance. The high level of morphological differentiation was also found among Iberian populations, supporting the already known complex history of the species in that region. Populations within other regions were differentiated at lower levels; however, the West Anatolian populations differed morphologically from the eastern ones. The described pattern of morphological differentiation supports the idea of the long-lasting existence of P. sylvestris in the south-European and Anatolian mountain regions. To conserve this variation, seed transfer between regions in the forest economy should be restricted.The research was financially supported by The Polish Ministry of Science (Contr. No. NN303 360535) and partly by Institute of Dendrology.Peer reviewe

Relationships among Cedrus libani, C. brevifolia and C. atlantica as revealed by the morphological and anatomical needle characters

The main aim of the present study was testing the value of the morphological and anatomical characteristics of the needles in distinguishing Cedrus atlantica, C. libani and C. brevifolia. Nine populations were sampled in their natural habit and 25 characters were used to describe the variation of the brachyblast needles and to analyze the differences between species. The results indicated that morphological and anatomical needle characters provide valuable tools in discrimination of the taxa. The scored differences were statistically significant, as revealed in the Tukey's t test, discrimination analysis and hierarchical analysis of variation. The results support treating C. libani, C. atlantica and C. brevifolia as independent species. © 2012 The Author(s).The collection of the majority of the material used in the present study was made possible through bilateral cooperation between the Polish Academy of Sciences and the Consejo Superior de Investigaciones Científicas (Spain) and unofficial cooperation between the Institute of Dendrology and the Faculty of Forestry of Kahramanmaraş Sutcu Imam University in Turkey. The study was partly sponsored by the Institute of Dendrology of the Polish Academy of Sciences.Peer Reviewe

Morphological differentiation supports the genetic pattern of the geographic structure of Juniperus thurifera (Cupressaceae)

12 p., mapas, tablas, gráf.Juniperus thurifera is an important component of woodland communities of dry sites within the West Mediterranean region and is characterised by a strongly disjunctive geographic range. Two subspecies were recognised, subsp. thurifera in Europe and subsp. africana in Africa. The aim of the study was the comparison of phenetic diversity to the pattern of AFLP geographic differentiation of the species described in the literature. The examination of phenetic diversity was based on the biometrical analysis of 17 populations using 12 morphological characters of cone and seed. The differences among populations were analysed using Student’s t test, analysis of discrimination, UPGMA agglomeration and hierarchical analysis of variance. The majority of morphological characters differentiated at a statistically significant level between populations and between J. thurifera subsp. thurifera and subsp. africana. Three groups of populations were detected using multivariate statistical analyses. The first, well separated, is subsp. africana, while the following two concern subsp. thurifera. The morphological differentiation of populations appeared similar to that described on the AFLP. The Gibraltar Straight appeared to be the most important barrier.Funding the work was partly sponsored by the Institute of Dendrology of the Polish Academy of Sciences. The collection of material was made possible due to the bilateral cooperation of the Polish Academy of Sciences with the Spanish National Research Council "Consejo Superior de Investigaciones Científicas".Peer reviewe

Morphological versus molecular markers to describe variability in Juniperus excelsa subsp. excelsa (Cupressaceae)

41 p.Background and aims: Juniperus excelsa M.-Bieb. is a major forest element in the mountains of the eastern part of Mediterranean and sub-Mediterranean regions. This study comprises the first morphological investigation covering a large part of the geographical range of J. excelsa and aims to verify the congruency between the morphological results and molecular results of a previous study. Methodology: We studied 14 populations sampled from Greece, Cyprus, Ukraine, Turkey and Lebanon, from which 11 have previously been investigated using molecular markers. Three hundred and ninety four individuals of J. excelsa were examined using nine biometric features characterising cones, seeds and shoots; and eight derived ratios. Statistical analyses were conducted in order to evaluate the intra and interpopulation morphological variability. Principal results: The level of intra-population variability observed did not show any geographic trends. The total variation mostly depended on the ratios of cone diameter/seed width and seed width/seed length. The discrimination analysis, the Ward agglomeration method and barrier analysis results showed a separation into three main clusters of the sampled populations. These results confirmed, in part, the geographic differentiation revealed by molecular markers with a lower level of differentiation and a less clear geographic pattern. The most differentiated populations using both markers corresponded to old, isolated populations in the high altitudes of Lebanon (>2000 m). Moreover a separation of the northern Turkish population from the southern Turkish populations was observed using both markers. Conclusions: Morphological variation together with genetic and biogeographic studies together make an effective good tool for detecting relict plant populations and also populations subjected to more intensive selection.The research was conducted within the statutory research programme of the Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland and supported by the Research Council of Saint-Joseph University of Beirut.Peer reviewe

TUBB4B Downregulation Is Critical for Increasing Migration of Metastatic Colon Cancer Cells

Tumor metastasis, the major problem for clinical oncology in colon cancer treatment, is linked with an epithelial-mesenchymal transition (EMT). The observed cellular transformation in this process is manifested by cell elongation, enhanced cell migration and invasion ability, coordinated by cytoskeleton reorganization. In the present study, we examined the role of tubulin-β4 (TUBB4B) downregulation that occurs during EMT in colon cancer cells, in the modulation of the function of microtubules. Based on biochemical and behavioral analysis (transmigration) we posit that the decrease of the TUBB4B level is critical for microtubule-vimentin interaction and contributes to the maintenance of polarity in migrating cells. The microscopic studies revealed that TUBB4B decrease is accompanied by cell elongation and increased number of matured focal adhesion sites, which is a characteristic of the cell metastatic stage. We also demonstrated faster polymerization of microtubules in cells with a lower level of TUBB4B. Simultaneous TUBB3 upregulation, reported during EMT, acts additively in this process. Our studies suggest that the protein level of TUBB4B could be used as a marker for detection of the preinvasive stages of the colon cancer cells. We also concluded that chemotherapy enriched to increase TUBB4B level and/or to stabilize microtubule polymerization might more effectively prevent metastasis in colon cancer development

Cyclic nucleotide-gated ion channels

Cyclic nucleotide-gated (CNG) channels are a novel class of cation channels first identified in retinal photoreceptor cells and subsequently found also in other sensory and nonsensory cells. CNG channels form heterotetrameric complexes consisting of two or three different types of channel subunits. Six different genes encoding CNG channels, four A subunits (A1 to A4) and two B subunits (B1and B3), give rise to three different channel types. Functionally,CNGchannels belong to the class of ligand-gated channels, which are activated by binding of ligand (cGMP) to a domain in the carboxyl terminal region, but structurally they are similar to voltage-dependent K+ channels. All channel subunits include six transmembrane segments (S1 to S6), a voltage-sensor motif (S4), a pore region (P) and a cGMP-binding domain. These channels are nonselective cation channels that do not discriminate well between monovalent and divalent ions and even pass divalent cations, in particular Ca2+. Activity of CNG channel is modulated by Ca2+/ calmodulin and by phosphorylation. Other factors may also be involved in channel regulation