Morphological differentiation of leaves in the relict tree Zelkova carpinifolia (Ulmaceae)

Zelkova carpinifolia is a relict tree occurring in refugial zones of south-western Eurasia. The main aim of the study was the biometrical comparison of the leaf characteristics of the species sampled in three regions of Transcaucasia. We aimed to test the hypotheses that (1) leaves from vegetative (L) shoots would be larger and more variable than those from fertile (S) shoots, (2) the leaves from the same shoot type express geographic patterns of morphological differentiation, similar to pattern described for genetic markers and (3) to verify the systematic position of Z. hyrcana and Z. carpinifolia subsp. yomraensis. The plant material was collected from 5 populations of Z. carpinifolia, one of Z. hyrcana and one of Z. carpinifolia subsp. yomraensis. The total 1482 leaves, 713 from L- and 769 S-type were measured using 26 characters. Our results show very high level of differences between leaves from the L- and S-type of shoots. The majority of leaf characters did not reveal dependence neither on geographic latitude, longitude and altitude nor on the basic climatic data. The results of multivariate analyses of S leaves revealed three group of populations, namely from (1) Colchis, (2) eastern Caucasus (3) Talysh. Thus, our biometric analyses revealed similar pattern to the haplotypic differentiation of Z. carpinifolia detected using chloroplast markers described in the literature. We did not detected significant differences in the leaf characters between supposed Z. hyrcana and/or Z. carpinifolia subsp. yomraensis, when compared to Z. carpinifolia, thus not confirming their separate taxonomic status

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

Effect of geographic range discontinuity on taxonomic differentiation of Abies cilicica

Three populations of Abies cilicica subsp. isaurica and four of A. cilicica subsp. cilicica were analyzed using 35 morphological and anatomical needle characters with the implementation of multivariate statistical methods to verify the differences between subspecies. Moreover, the possible geographic differentiation of A. cilicica subsp. cilicica populations from the East Taurus and Lebanon Mountains was examined. Abies cilicica subsp. isaurica has been distinguished from A. cilicica subsp. cilicica by its glabrous young shoots and resinous buds. We detected that needles of A. cilicica subsp. isaurica are longer, broader and thicker, with a higher number of stomata rows, and larger cells of the epidermis, hypodermis and endodermis than A. cilicica subsp. cilicica. Additionally, A. cilicica subsp. isaurica needles have frequently rounded to obtuse-acute apex and resinous canals positioned more centrally inside the mesophyll than needles of A. cilicica subsp. cilicica. This indicates that a set of most of the tested needle characters can be used to distinguish the subspecies; however, any of characters enable that when used separately. Morphological and anatomical distinctiveness between these two taxa justify their recognition at the subspecies rank. Additionally, the populations of A. cilicica subsp. cilicica from the East Taurus and Lebanon are morphologically different. This geographic differentiation of populations is congruent with results provided by genetic analyses of nuclear microsatellites markers (nSSR)

Validation of the Reference Genes for Expression Analysis in the Hippocampus after Transient Ischemia/Reperfusion Injury in Gerbil Brain

Transient brain ischemia in gerbils is a common model to study the mechanisms of neuronal changes in the hippocampus. In cornu ammonnis 2–3, dentate gyrus (CA2-3,DG) regions of the hippocampus, neurons are resistant to 5-min ischemia/reperfusion (I/R) insult, while cornu ammonnis 1 (CA1) is found to be I/R-vulnerable. The quantitative polymerase chain reaction (qRT-PCR) is widely used to study the expression of genes involved in these phenomena. It requires stable and reliable genes for normalization, which is crucial for comparable and reproducible analyses of expression changes of the genes of interest. The aim of this study was to determine the best housekeeping gene for the I/R gerbil model in two parts of the hippocampus in controls and at 3, 48, and 72 h after recanalization. We selected and tested six reference genes frequently used in central nervous system studies: Gapdh, Actb, 18S rRNA, Hprt1, Hmbs, Ywhaz, and additionally Bud23, using RefFinder, a comprehensive tool based on four commonly used algorithms: delta cycle threshold (Ct), BestKeeper, NormFinder, and geNorm, while Hprt1 and Hmbs were the most stable ones in CA2-3,DG. Hmbs was the most stable in the whole hippocampal formation. This indicates that the general use of Hmbs, especially in combination with Gapdh, a highly expressed reference gene, seems to be suitable for qRT-PCR normalization in all hippocampal regions in this model

Tree-like pines on the Mshana peat bog in the Gorgany Mountains: a trace of Pinus uliginosa migration in the East Carpathians?

The taxonomic position of the population of tree-like, mostly polycormic individuals of pines from the Mshana peat bog in the Gorgany Mountains (East Carpathians, Ukraine) has been studied on the basis of the morphological characteristics of cones and needles, and anatomical characteristics of the needles. These features have been compared with the surrounding Pinus mugo population as well as P. uliginosa, P. mugo, P. sylvestris and P. uncinata from natural populations of the taxa. Tree-like individuals were found to have the most similar needles to P. uliginosa, but most similar cone characteristics to P. mugo. It was concluded, that the tree-like population has a relic character and can present the trace of the early migration of P. uliginosa from the West and its hybridisation with P. mugo

Taxonomic and geographic differentiation of <i>Pinus mugo</i> complex on the needle characteristics

<div><p>The phenotypic differentiation of <i>Pinus mugo</i> complex was verified using 31 populations of <i>P. mugo sensu stricto</i>, 11 of <i>P. uncinata</i>, five of <i>P. uliginosa</i>, one of the potential hybrids <i>P. uliginosa</i> × <i>P. mugo</i> and three of <i>P. sylvestris</i>, the latter as a control. The 22 morphological and anatomical needle characteristics were measured and statistically examined to describe the taxa and the population within the taxa differentiation. All the taxa of the <i>P. mugo</i> complex differed significantly from <i>P. sylvestris</i> in most of the verified needle characteristics. Within <i>P. mugo</i> complex, populations of <i>P. uncinata</i> were clearly distinguished from <i>P. mugo s. s</i>. The population of potential hybrid origin was the most similar to <i>P. uliginosa</i>. Populations of the latter taxon were strongly differentiated; some of them were closer to <i>P. uncinata</i>, and others to <i>P. mugo s. s</i>. Within the whole sampled data, three geographic groups of populations were detected: the first included <i>P. uncinata</i> and two of <i>P. uliginosa</i>, the second contained East and South Carpathian <i>P. mugo s. s</i>. with the presumed hybrid population, and the third contained all the other populations of <i>P. mugo s. s</i>. and <i>P. uliginosa</i>. Within <i>P. mugo s. s</i>., the Sudetan populations formed a separate group. <i>Pinus uncinata</i> from the Pyrenees reflected a high level of differentiation. The marginal populations of this taxon (Cebollera, Gúdar, Massif Central) also differed from those in the Pyrenees. The phenotypic differentiation of taxa and populations appeared similar to that which was detected based on <i>cp</i>DNA markers.</p></div

Morphology supports the geographic pattern of genetic differentiation of Pinus sylvestris (Pinaceae) in the Iberian Peninsula

Pinus sylvestris from the Iberian Peninsula was biometrically compared, using needle morphological and anatomical characteristics from 15, and cone morphological characteristics from nine natural populations. Samples of Scots pine represent subspecies nevadensis and varieties pyrenaica, catalaunica, and iberica. Analyses included 25 needle and 17 cone characteristics and numerical methods (principal component analysis, discrimination analysis, agglomeration on Euclidean/Mahalanobis¿ distances). A strong differences were detected between P. sylvestris subsp. nevadensis when compared to varieties pyrenaica and iberica, and a closer relationship to var. catalaunica in needle characteristics. In cone characteristics, the differences were at a similar level. Alien individuals were found within every taxon and population. Samples from the southern part of Sistema Central had the highest level of alien individuals. The geographic pattern of differentiation resembles patterns previously revealed using molecular and isoenzymatic markers. We could not detect characteristics specific to either P. sylvestris subsp. nevadensis or varieties of P. sylvestris subsp. sylvestris.This research was financially supported by the Polish Ministry of Science and Higher Education (Contr. No. NN303 360535) and partly by the Institute of Dendrology PAS under statutory activity.Introduction Material and methods Material Measurement procedures Statitstical analyses Results Variation and correlation of characteristics Differences between taxa Discusion Conclusion Supplemental material Disclosure statement Additional information Reference

Mitofusin 2 Deficiency Affects Energy Metabolism and Mitochondrial Biogenesis in MEF Cells.

Mitofusin 2 (Mfn2), mitochondrial outer membrane protein which is involved in rearrangement of these organelles, was first described in pathology of hypertension and diabetes, and more recently much attention is paid to its functions in Charcot-Marie-Tooth type 2A neuropathy (CMT2A). Here, cellular energy metabolism was investigated in mouse embryonic fibroblasts (MEF) differing in the presence of the Mfn2 gene; control (MEFwt) and with Mfn2 gene depleted MEFMfn2-/-. These two cell lines were compared in terms of various parameters characterizing mitochondrial bioenergetics. Here, we have shown that relative rate of proliferation of MEFMfn2-/- cells versus control fibroblasts depend on serum supplementation of the growth media. Moreover, MEFMfn2-/- cells exhibited significantly increased respiration rate in comparison to MEFwt, regardless of serum supplementation of the medium. This effect was correlated with increased level of mitochondrial markers (TOM20 and NAO) as well as mitochondrial transcription factor A (TFAM) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) protein levels and unchanged total ATP content. Interestingly, mitochondrial DNA content in MEFMfn2-/- cells was not reduced. Fundamentally, these results are in contrast to a commonly accepted belief that mitofusin 2 deficiency inevitably results in debilitation of mitochondrial energy metabolism. However, we suggest a balance between negative metabolic consequences of mitofusin 2 deficiency and adaptive processes exemplified by increased level of PGC-1α and TFAM transcription factor which prevent an excessive depletion of mtDNA and severe impairment of cell metabolism