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31.
ANGEL M. ROMO F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1992,108(3):203-212
ROMO, A. M., 1992. Contribution to the taxonomy and nomenclature of the vascular plants of Morocco. As a result of studies on the flora of Morocco, a number of new taxa and a series of new nomenclature combinations are proposed which are more in line with current knowledge. Three new taxa are described: Dianthus atlantica from the Great Atlas; Ranunculus spicatus Desf. subsp. fontqueri Romo, endemic to Er Rif, and a hybrid: Saxifraga × fontqueri Romo (= S. crenata Psau & Font Quer × Saxifraga globulifera Desf.). The following new combinations are made: Astragalus gombo Cosson & Durieu subsp. pseudogombo (Fernandez Casas) Romo, Avenula bromoides (Gouan) H. Scholz subsp. cincinnatus (Ten.) Romo, Chaenorrhinum origanifolium (L.) Fourr. subsp. flexuosum (Desf.) Romo, Digitalis laciniata Lindley subsp. riphaea (Pau & Font Quer) Romo, Digitalis purpurea subsp. mauretanica (Humbert & Maire) Romo, Lavandula pedunculata Miller subsp. atlantica (Braun-Blanquet) Romo, Paeonia coriacea Boiss. var. maroccana (Pau & Font Quer) Romo, Sideritis arborescens Bentham subsp. antiallantica (Maire) Romo. 相似文献
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AVITAL STOLOV † ANGEL VALVERDE † PAMELA RONALD SAUL BURDMAN 《Molecular Plant Pathology》2007,8(1):93-101
The RaxHR two-component regulatory system (TCS) of the rice pathogen Xanthomonas oryzae pv. oryzae is required for AvrXa21 activity. RaxH is a typical transmembrane histidine protein kinase (HK), whereas RaxR is its concomitant response regulator (RR). Here, we report the isolation of soluble, active amounts of recombinant His-tagged full-length RaxH and RaxR following growth of Escherichia coli over-expressing strains in the presence of sorbitol and glycine betaine. Full-length His-RaxH showed similar autophosphorylation activities to that of a truncated version of the protein (His-t-RaxH), lacking the N-terminal transmembrane region. Transphosphorylation assays revealed that only full-length RaxH was able to induce phosphorylation of His-RaxR, indicating that the N-terminal region of RaxH may be required for transphosphorylation of RaxR. Using site-directed mutagenesis we also demonstrated that residues histidine 222 in RaxH and aspartate 51 in RaxR are essential for phosphorylation activities of these proteins. Utilization of compatible solutes may be widely applied for purification of soluble, active recombinant transmembrane proteins, and in particular for purification of transmembrane HKs. 相似文献
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MIGUEL ANGEL GONZÁLEZ‐PÉREZ M. DOLORES LLEDÓ CHRISTIAN LEXER MICHAEL FAY MANUEL MARRERO ANGEL BAÑARES‐BAUDET EDUARDO CARQUÉ PEDRO A. SOSA 《Botanical journal of the Linnean Society. Linnean Society of London》2009,160(4):429-441
Variation at five polymorphic microsatellite loci was used to investigate genetic diversity and differentiation of two tetraploid Canarian endemics, Bencomia exstipulata and B. caudata. Data were analysed and are discussed in terms of tetrasomic (autotetraploid) and disomic (allotetraploid) inheritance. In both cases, genetic diversity values were similar to those described in other tetraploid plant species. High genetic differentiation between the only two described natural populations of B. exstipulata was detected (FST = 0.411). Bayesian cluster analysis revealed a geographical structure with distinct genetic groups from each island. High genetic differentiation and low genetic diversity of the B. exstipulata population from Tenerife suggest a recent population bottleneck, perhaps caused by the most recent major volcanic eruption, for this natural locality. This may be heightened by possible inbreeding depression and the monoecy of these species. Polymorphic microsatellite loci were also tested across all species in the Bencomia alliance. These reliably amplified the target sequence, suggesting a high degree of conservation of the sequences flanking the microsatellites. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 429–441. 相似文献
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ANGEL JL 《The American journal of anatomy》1948,83(2):223-246
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CERVERA JUAN LUCAS; GOSLINER TERRENCE M.; GARCIA GOMEZ JOSE CARLOS; ORTEA JESUS ANGEL 《Journal of Molluscan Studies》2000,66(3):301-312
Berthella canariensis is described from Canary
Islands. Themantle is smooth and its ground colour is grey, with
black andopaque white spots scattered regularly all over the dorsal
surface.White spots are less abundant than black ones. The posterior
halfof the mantle has areas of with a paler ground colour that are
variablein size. Berthella canariensis has several features
that distinguishit from other described members of
Berthella. It had a broadradula with numerous teeth per
half-row. However, other aspectsof its anatomy, such as the absence
of a medial buccal glandand the presence of a tuberculate gill,
distinguish it fromother species with a broad radula. As the present species has two features found in some speciesof
Pleurobranchus and several new higher taxa have been
describedrecently, Willan's (1987) phylogenetic hypothesis was
re-analysed.This analysis largely supports the hypothesis presented
by Willan. The sister-group relationship of B. Canariensis
with B. californiais supported by two synapomorphies. The
relationship of thesetwo species to other species of
Berthella is poorly resolvedin the present analysis and
requires additional study of allmembers of the genus. Similarly,
questions of the monophylyof Bathyberthella, Polictenidia,
Parabathyberthella, Tomthompsoniaand Berthella require
the consideration of additional speciesand comparison with other
member of Berthella and Berthellina. Despite the
need for further study, the mohophyly of the cladecontaining
Bathyberthella, Polictenidia, Parabathyberthellais well
supported. Similarly, numerous synapomorphic featuresconfirm the
monophyly of the clade containing Bathyberthella,Polictenidia,
Parabathyberthella, Tomthompsonia, Berthellinaand
Berthella, and its sister-group relationship with the
Pleurobranchus. The present study reveals that the
Notaspidea have three distinctconfigurations of triaulic reproductive
systems, not previouslydifferentiated. (Received 19 January 1998; accepted 15 November 1999) 相似文献
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ANA PERERA RAQUEL VASCONCELOS D. JAMES HARRIS RICHARD P. BROWN MIGUEL ANGEL CARRETERO VALENTIN PÉREZ-MELLADO 《Biological journal of the Linnean Society. Linnean Society of London》2007,90(3):479-490
Lacerta perspicillata is a north-west African lacertid lizard that shows considerable intraspecific variation, with three subspecies described on the basis of colour pattern and body size. Recent observations of a population containing two morphological forms and more than one deep genetic lineage, as well as an apparent lack of concordance between forms and genetic lineages, suggest that the complexity is greater than previously thought. To analyse and quantify this variation, we studied the variability within this species at two levels: (1) external morphology (multivariate analysis of scalation, body dimensions, and colour pattern) and (2) mtDNA (sequencing and single-strand confirmation polymorphism analysis). Fifty-two individuals were studied at Taza, northern Morocco. Two morphological groupings (ostensibly representing two previously described subspecies) and two deep mtDNA lineages were detected at this site, with complete correspondence between the two. This, together with an apparent lack of hybrids, would normally support respective full species recognition. However, analysis of 98 individuals from other populations demonstrated that the situation is highly complex with the same genetic lineages having reversed morphotypes in other areas, making such a designation difficult. Across the other studied populations, we found no support for any of the currently recognized subspecies. The lack of congruence between mtDNA lineages and morphometric patterns (in some cases) and the morphological similarity among lizards from different lineages suggest ecophenotypic convergence or multiple introgressive hybridization. The study highlights the tremendous complexity that may exist within a taxon and the inadequacy of older alpha-taxonomy based designations in describing it. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 479–490. 相似文献
40.
PEDRO LUIS VALVERDE FERNANDO VITE JOSÉ ALEJANDRO ZAVALA-HURTADO 《Botanical journal of the Linnean Society. Linnean Society of London》1996,122(2):155-161
A supposed hybrid population ( Agave peacockii ) between Agave marmorata and Agave kerchovei in a semiarid ecosystem at Zapotitlán Salinas, in the Mexican State of Puebla, was investigated, and its hybrid status corroborated in morphometric terms. A Stepwise Discriminant Analysis of the ratios: Number of leaved Rosette diameter, Leaf width/Leaf length, Number of spines/Leaf length, Distance between the upper spine and the tip of the leaf/Leaf length, and Distance between the upper spine and the tip of the leaf/Number of spines, supported our hypothesis of the existence of these naturally occurring hybrids, which are intermediate and distinct from the parental species. A null model was constructed to contrast the real case with a possible artifact, and the results also supported our hypothesis. The possible meaning of this kind of hybridization is discussed. 相似文献