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41.
Chloroplast DNA restriction site variation was examined for 35 taxa in theVernonieae and four outgroup tribes, using 17 restriction enzymes mapped for ca. 900 restriction sites per species; 139 mutations were found to be phylogenetically informative. Phylogenetic trees were constructed using Wagner and weighted parsimony, and evaluated by bootstrap and decay analyses. Relationships of Old and New World taxa indicate complex geographical relationships; there was no clear geographic separation by hemisphere. The relationships between Old and New World Vernonias found here support prior morphological analyses. The sister group to all New and most Old World taxa was composed of a small group of Old World species including yellow-flowered, trinervate-leaved species previously postulated to be basal in the tribe. The majority of both New and Old World taxa are derived from a lineage beginning with the monotypic genusStokesia, an endemic of the southeastern United States. The genusVernonia was also found to be paraphyletic within both the New and Old World. Available data do not support either the separation ofVernonia or the tribeVernonieae into geographically distinct lineages. The pattern of relationships within theVernonieae for taxa from North America, Asia, Africa, Central and South America is most similar to that of several other groups of both plants and animals with a boreotropical origin, rather than an origin in Gondwanaland. Such a pattern of distribution suggests more ancient vicariant events than are routinely postulated for theAsteraceae. 相似文献
42.
Plasma membrane phosphatidic acid phosphohydrolase (PAPH) plays an important role in signal transduction by converting phosphatidic acid to diacylglycerol. PAPH-2, a Mg2+-independent, detergent-dependent enzyme involved in cellular signal transduction, is reportedly absent from the plasma membranes of neutrophilic leukocytes, a cell that responds to metabolic stimulation with abundant phospholipase
-dependent diacylglycerol generation. The present study was designed to resolve this discrepancy, focusing on the influence of cellular disruption techniques, detergenta availability and cation sensitivity on the apparent distribution of PAPH in neutrophil sub-cellular fractions. The results clearly indicate the presence of two distinct types of PAPH within the particulate and cytosolic fractions of disrupted cells. Unlike the cytosolic enzyme, the particulate enzyme was not potentiated by magnesium and was strongly detergent-dependent. The soluble and particulate enzymes displayed dissimilar pH profiles. Separation of neutrophil particulate material into fractions rich in plasma membranes, specific granules and azurophilic granules by high speed discontinuous density gradient centrifugation revealed that the majority of the particulate activity was confined to plasma membranes. This activity was not inhibited by pretreatment with n-ethyl-maleimide in concentrations as high as 25 mM. PAPH activity recovered in the cytosolic fraction of disrupted neutrophils was almost completely inhibited by 5.0 mM n-ethylmaleimide. We conclude that resting neutrophils possess n-ethylmaleimide-resistant PAPH (type 2) within their plasma membranes. This enzyme may markedly influence the kinetics of cell activation by metabolizing second messengers generated as a result of activation of plasma membrane phospholipase D. 相似文献
43.
David M. Spooner Gregory J. Anderson Robert K. Jansen 《American journal of botany》1993,80(6):676-688
We used chloroplast DNA restriction site analysis to test hypotheses of relationships of Solarium subgenus Potatoe (including potatoes and pepinos), two other Solanum, Cyphomandra (the tree tomatoes), and Lycopersicon (the tomatoes). Capsicum and Datura were used as outgroups. The results support two main clades among the taxa we studied: 1) Solanum subgenus Potatoe and Lycopersicon; and 2) other Solanum and Cyphomandra. Within the first clade, the following groups were supported: a) sect. Basarthrum and sect. Anarrhichomenum; b) sect. Etuberosum; c) sect. Petota; d) sect. Juglandifolium, including subsect. Lycopersicoides; and e) the genus Lycopersicon. These results, in combination with an analysis of morphological data, advocate the controversial, but previously suggested, treatment of Lycopersicon as congeneric with Solanum in subgenus Potatoe. Thus, the cultivated tomato will be recognized as Solanum lycopersicum L. Solanum chmielewskii and Solanum lycopersicum var. cerasiforme are proposed as new combinations; Solanum neorickii is proposed as a new name for Lycopersicon parviflorum. Our data also suggest that Cyphomandra should be included within Solanum. 相似文献
44.
Restriction site mapping of chloroplast DNA from 31 species representing 26 genera of theRanunculaceae was performed using eleven restriction endonucleases. The chloroplast genome varies in length from approximately 152 to 160 kb. Length variants are frequent in theRanunculaceae and range from usually less than 300 bp to rarely 1.5 kb. The inverted repeat is extended into the large single copy (LSC) region by 4–4.5 kb inAnemone, Clematis, Clematopsis, Hepatica, Knowltonia, andPulsatilla. Several inversions are present in the LSC-region of the cpDNA in all these genera and inAdonis. The frequency of restriction site mutations varies within the chloroplast genome in theRanunculaceae between 4 and 32 mutations per kilobase, and is lowest in the inverted repeat and the regions containing the ATPase-genes and the genespsaA, psaB, psbA, rpoB, andrbcL. A total of 547 phylogenetically informative restriction sites was utilized in cladistic analyses of the family using Wagner, Dollo, and weighted parsimony. These three parsimony analyses result in different tree topologies. Four, six, and one equally most parsimonious trees were obtained with Wagner, Dollo, and weighted parsimony, respectively. The amount of support for the monophyletic groups was evaluated using bootstrapping and decay analysis. All three parsimony methods suggest thatHydrastis is the sister group to the remainder of theRanunculaceae, and that theAnemone-Clematis group, which shares several derived cpDNA rearrangements, is monophyletic. Only a few of the traditional groups in theRanunculaceae are supported by cpDNA restriction side data. Only Dollo parsimony provides support for the hypothesis thatThalictroideae andRanunculoideae are monophyletic. 相似文献
45.
Maarten Jaap Erik Broekman Selwyn Hoeks Rosa Freriks Merel M. Langendoen Katharina M. Runge Ecaterina Savenco Ruben ter Harmsel Mark A. J. Huijbregts Marlee A. Tucker 《Global Ecology and Biogeography》2023,32(2):198-205
Motivation
Home range is a common measure of use of space by animals because it provides ecological information that is useful for conservation applications. In macroecological studies, values are typically aggregated to species means to examine general patterns of use of space by animals. However, this ignores the environmental context in which the home range was estimated and does not account for intraspecific variation in home range size. In addition, the focus of macroecological studies on home ranges has historically been biased towards terrestrial mammals. The use of aggregated numbers and the terrestrial focus limit our ability to examine home-range patterns across different environments, their variation in time and variation between different levels of organization. Here, we introduce HomeRange, a global database with 75,611 home-range values across 960 different species of mammals, including terrestrial, aquatic and aerial species.Main types of variables contained
The dataset contains estimates of home ranges of mammals, species names, methodological information on data collection, method of home-range estimation, period of data collection, study coordinates and name of location, in addition to species traits derived from the studies, such as body mass, life stage, reproductive status and locomotor habit.Spatial location and grain
The collected data are distributed globally. Across studies, the spatial accuracy varies, with the coarsest resolution being 1°.Time period and grain
The data represent information published between 1939 and 2022. Across studies, the temporal accuracy varies; some studies report start and end dates specific to the day, whereas for other studies only the month or year is reported.Major taxa and level of measurement
Mammalian species from 24 of the 27 different taxonomic orders. Home-range estimates range from individual-level values to population-level averages.Software format
Data are supplied as a comma-delimited text file (.csv) and can be loaded directly into R using the “HomeRange” R package ( https://github.com/SHoeks/HomeRange ). 相似文献46.
Dirk T. Witte Frank J. Bruggeman Jan Piet Franke Swier Copinga Johanna M. Jansen Rokus A. De Zeeuw 《Chirality》1993,5(7):545-553
Direct enantiomeric separations of 17 chiral amidotetralins by means of high performance liquid chromatography were performed on stationary phases composed of tris(3,5-dimethylphenylcarbamate) derivatives of cellulose and amylose, coated on silica gel. The enantiomers of 15 out of 17 amidotetralins were resolved with a resolution of more than 1.5 by at least one of the chiral stationary phases. The stationary phases showed complementary results with regard to the separation of the amidotetralins, that is, pairs that did not separate on the cellulose-type column were well separated on the amylose-type column, and vice versa. There was no significant correlation between the chromatographic properties of the chiral stationary phases. © 1993 Wiley-Liss, Inc. 相似文献
47.
48.
Intraspecific chloroplast DNA polymorphisms were examined for 51 populations of seven species in the genus Krigia. A total of 1,100 restriction sites was surveyed and 46 of these were variable at the intraspecific level. Twenty-two of the variable sites were found within K. virginica, giving this species one of the highest levels of intraspecific chloroplast DNA divergence of any examined species. In contrast, no restriction site variation was detected within K. dandelion, K. wrightii, and K. occidentalis. Five polymorphisms were identified from the 16 populations of the K. cespitosa-gracilis complex, but no mutations distinguished the K. cespitosa and K. gracilis types. Krigia montana and K. biflora showed 11 and eight restriction site polymorphisms, respectively. The chloroplast genome of the hexaploid K. montana was derived from the diploid K. biflora rather than the tetraploid K. montana. High levels of polymorphism were found in species having different ploidy levels, such as K. virginica, K. biflora, and K. montana. Furthermore, most mutations found in these three species were recorded from the tetraploid lineages. As a result, evolutionary rates between different ploidy levels differ significantly. The chloroplast DNA restriction site data suggest that all surveyed populations of the autotetraploid K. virginica originated from a common ancestor. Our results also indicate that certain regions of the chloroplast genome have changed more rapidly than others and have the potential to resolve evolutionary questions at the population level. 相似文献
49.
50.
Phylogenetic relationships among 31 species representing variously Helianthus, Helianthopsis, Heliomeris, Simsia, Viguiera, and Tithonia were assessed by chloroplast DNA restriction site mapping. A total of 147 mutations including 92 informative ones was detected using 16 restriction enzymes, with an estimated sequence divergence within the group of 1.4%. Parsimony analysis produced a single most parsimonious tree with a length of 161 steps and a consistency index of 0.91. Statistically significant clades, as assessed by the bootstrap method, correspond to a number of taxa recognized previously, including Helianthus (3 species), Helianthopsis (5 species), and several groups within Viguiera, including sect. Maculatae (4 species), the Baja California group (6 species), sect. Paradosa (2 species) and V. dentata (3 samples). However, species of Viguiera collectively form a highly paraphyletic group relative to species of other genera. Helianthus and Helianthopsis were separated into different clades, supporting their recent segregation. Placement of H. porteri in Helianthus rather than Heliomeris was confirmed; the single sample of the latter genus was most similar to the Baja California group of Viguiera. An expected relationship between Simsia (2 species) and one member of Viguiera ser. Grammatoglossae was confirmed (although not with two other putatively related members of Viguiera) and an unexpected relationship between Simsia and Tithonia was suggested. The presence of Mexican taxa as the more basal groups in the tree points toward a possible Mexican origin for Viguiera and related genera. A molecular clock hypothesis is rejected in many pairwise comparisons involving woody taxa with herbaceous ones, although it could not be rejected in most pairwise comparisons involving taxa of similar habit. 相似文献