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1.
Onobrychis dushanbensis Ranjbar, Vitek & Karamian, a new Fabaceae species endemic to Tajikistan, is described and illustrated. The new species belongs to Onobrychis Miller subgen. Sisyrosema (Bunge) Grossheim sect. Hymenobrychis DC. It is closely related to O. chorassanica Bunge and O. seravschanica B. Fedtsch., but is easily distinguished by its purple flowers with darker venation (vs yellowish with purple venation), with wings 9–10 mm long (vs wings 4–5 mm long) and bracts 14–15 mm long (vs bracts 4–5 mm long). The relationships between the new and closely related species are discussed.  相似文献   

2.
The new series Elatostema section Elatostema series Albopilosoides Q.Lin & L.D.Duan (Urticaceae) is described, and two new species of Elatostema, namely Elatostema albopilosoides Q.Lin & L.D.Duan and Elatostema purpureum Q.Lin & L.D.Duan. from south Guizhou province, south‐west China are described and illustrated. Both species were found growing only at the base of a large limestone chamber at an altitude of c. 800 m. Elatostema albopilosoides is morphologically similar to E. albopilosum W.T.Wang, but differs by having female inflorescences with peduncles 10–60 mm long (0–1.5 mm long in E. albopilosum) and receptacles 7–27 mm long, 7–24 mm wide (E. albopilosum: 1–4 mm long and 1–3 mm wide). Elatostema purpureum is also morphologically similar to E. albopilosum, but has stipules 5–6 mm long, 0.8–1.5 mm wide (4–7 mm long, 1.5–2.8 mm wide in E. albopilosum) and leaf blades obliquely elliptical to obliquely oblong‐obovate, 3.5–7.5 mm long and 1.5–2.5 mm wide (obliquely narrowly oblanceolate‐oblong, 12–17 cm long, 3–5 cm wide in E. purpureum:). © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 674–680.  相似文献   

3.
Hitherto, the only known mutant gene leading to the long‐hair phenotype in mammals is the fibroblast growth factor 5 (FGF5). In many dog breeds, the previously discovered FGF5:p.Cys95Phe mutation appeared completely concordant with the long‐hair phenotype, but for some breeds, the long‐hair phenotype could not be resolved. First, we studied the role of the FGF5:p.Cys95Phe and FGF5:g.145_150dupACCAGC mutations in 268 dogs descending from 27 breeds and seven wolves. As these mutations did not explain all the long‐hair phenotypes, all exons and their neighbouring regions of FGF5 were re‐sequenced. We detected three novel mutations in the coding sequence and one novel non‐coding splice‐site mutation in FGF5 associated with the long‐hair phenotype. The FGF5:p.Ala193Val polymorphism was perfectly consistent with long hair in Akitas and probably in Siberian huskies, too. Dogs of the long‐hair breed Samoyed were either homozygous or compound heterozygous for the FGF5:p.Ala193Val or the FGF5:p.Cys95Phe polymorphisms respectively. The two newly detected polymorphisms FGF5:c.559_560dupGG and FGF5:g.8193T>A and the known mutation FGF5:p.Cys95Phe explained the long‐hair phenotype of all Afghan hounds analysed. An FGF5:c.556_571del16 mutation was found in one longhaired Eurasier. All long‐hair‐associated mutations follow a recessive mode of inheritance, and allelic heterogeneity was a common finding in breeds other than Akita.  相似文献   

4.
A clone isolated from a Drosophila auraria heat-shock cDNA library presents two long, antiparallel, coupled (LAC) open reading frames (ORFs). One strand ORF is 1,929 nucleotides long and exhibits great identity (87.5% at the nucleotide level and 94% at the amino acid level) with the hsp70 gene copies of D. melanogaster, while the second strand ORF, in antiparallel in-frame register arrangement, is 1,839 nucleotides long and exhibits 32% identity with a putative, recently identified, NAD+-dependent glutamate dehydrogenase (NAD+-GDH). The overlap of the two ORFs is 1,824 nucleotides long. Computational analysis shows that this LAC ORF arrangement is conserved in other hsp70 loci in a wide range of organisms, raising questions about possible evolutionary benefits of such a peculiar genomic organization.Correspondence to: Z.G. Scouras  相似文献   

5.
Onosma maculata Ranjbar & Almasi, a new Boraginaceae species endemic to Iran, is described and illustrated. The new species belongs to Onosma sect. Onosma subsect. Onosma. It is closely related to O. nervosa Riedl, but is easily distinguished by its spotted stem and peduncle (vs no spots), leaves 14–23 cm long (vs leaves 4–12 cm long), pedicel 5–15 mm long (vs pedicel 3–5 mm long), higher density of hairs, and glabrous nutlet (vs villous). Moreover, meiotic chromosome number and behavior were studied in two populations of the new species and it was found to be diploid with 2n = 2x = 16.  相似文献   

6.
依据植物野外和腊叶标本形态观察以及小叶脉序观察,对贺兰山岩黄耆(豆科)及其近缘种进行了分类学研究。结果表明:贺兰山岩黄耆及其近缘种之间较为稳定的差别体现在花器官的形态方面。贺兰山岩黄耆与短翼岩黄耆的主要区别特征是小苞片长为萼筒的1~2倍,旗瓣与龙骨瓣近等长,而后者的小苞片长为萼筒的0.5~0.8倍,旗瓣长为龙骨瓣的0.8倍。贺兰山岩黄耆与华北岩黄耆和费尔干岩黄耆的主要区别是翼瓣长为龙骨瓣的0.3~0.5倍,而后二者的翼瓣长均为龙骨瓣的0.7~0.8倍。在小叶脉序特征方面,贺兰山岩黄耆与短翼岩黄耆和华北岩黄耆近似,均为小叶一级脉纤细,二级脉不分支,二级脉环外有较多网结三级脉,具少量复合二级间脉或不明显,而费尔干岩黄耆小叶一级脉粗,二级脉多分支,二级脉环外有少量网结三级脉,具明显的简单二级间脉。此外,小叶脉序特征可能在岩黄耆属组间关系的探讨中发挥作用。  相似文献   

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Chitinase 1 (Chil) is the major extracellular chitinase from the hyperparasitic fungus, Aphanocladium album. We determined the complete sequence of the chromosomal and cDNA copies of the structural gene (chi1) coding for Chil. The coding region is interrupted by three short introns (55, 53 and 49 bp long). Chil is 423 aa long and begins with a stretch of 34 aa not found in the mature protein. The Chil sequence presents overall similarities with bacterial chitinases from Serratia marcescens and Bacillus circulans. Compared with other chitinases, A. album Chi1 has only two short similarity regions (12 and 8 aa long), which are also found in bacterial, yeast and some plant chitinases.  相似文献   

10.
Rheoptilum gen. n. is established for R. arni sp. n. and R. lokohensis sp. n. from Madagascar. Imaginal and larval stages are both described. Rheoptilum nymphs have two important adaptations: mouthparts are highly modified for scraping and the habitus is adapted for fast flowing waters. The genus possesses an extremely broad labrum with distal margin almost straight, incisors almost fused, right prostheca long and slender, caudal filament reduced to a single segment, legs long and slender, dorsally bordered with long and thin setae and the body dorsoventrally flattened. This combination of features distinguishes Rheoptilum from other Afro-Malagasy baetid genera. The phylogenetic position of this new genus is discussed.  相似文献   

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A new species of freshwater eutardigrade, Diphascon (Adropion) tricuspidatum sp. nov., is described from Antarctica. It has a narrow bucco-pharyngeal tube without drop-shaped thickening, a pharyngeal bulb with small apophyses, three short macroplacoids and a small microplacoid, and very long outer claws with long and divergent accessory points. Accepted: 27 August 1999  相似文献   

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Most of the bacteriophages (phages) currently reported in Enterococcus spp. belong to tailed families of bacteriophages Podoviridae, Siphoviridae, and Myoviridae. There is a little information on non-tailed bacteriophages isolated from enterococci. Samples of sewage and piggery effluents were tested on pig and chicken isolates of Enterococcus faecalis, E. faecium and E. gallinarum for lytic phages. In addition, isolates were exposed to mitomycin C to induce lysogenic phages. Bacteriophages that were detected were visualized by electron microscopy. Ten bacteriophages were of isometric shape with long flexible or non-flexible tails, while one had a long head with a long flexible tail; all contained double-stranded DNA molecules. Seven Polyhedral, filamentous, and pleomorphic-shaped phages containing DNA or RNA were also observed. The pleomorphic phages were droplet- or lemon-shaped in morphology. This study is the first report on polyhedral phages in Enterococcus spp. of animal origin and also the first report of filamentous and pleomorphic phages in enterococci.  相似文献   

15.
The new, monotypic camaenid genus Arnhemtrachia is described for the new species Arnhemtrachia ramingining from Ramingining, Arnhem Land, Northern Territory, Australia with additional records from the Gove Peninsula in eastern Arnhem Land. This camaenid is characterised by a combination of distinct morphological features, such as a small, discoidal, keeled shell with regular axial ribs, open umbilicus and simple, rounded aperture as well as a reproductive system with a long epiphallus possessing a long flagellum and absence of a penial sheath, with a flap on the penial wall which transverses longitudinal pilasters, and a long, simple bursa copulatrix. Based on comparative morphology, Arnhemtrachia reveals affinities with Trozena morata Iredale, 1838 from NE Queensland.  相似文献   

16.
In this work the structural variations of Terminal Inverted Repeats (TIR) of Bari like transposons in Drosophila species has been studied. The aim is to try and assess the relevance of different variants in the evolutionary distribution of Bari elements. Bari is a member of the widespread Tc1 superfamily of transposable elements that has colonized most species of the Drosophila genus. We previously reported the structure of two related elements that differ in their TIR organization: Bari1 harbouring 26-bp TIR (short TIRs) and Bari2 with about 250-bp TIR (long TIR). While elements with short TIRs are complete and potentially autonomous, long ones are invariably composed of defective copies. The results show that in D. pseudobscura, D. persimilis and D. mojavensis, there is a third class of Bari elements, Bari3, that exhibit a long TIR structure and are not defective. Phylogenetic relationships among reconstructed transposases are consistent with the three subfamilies sharing a common origin. However, the final TIR organization into long or short structure is not related by descent but appears to be lineage-specific. Furthermore, we show that, independently of origin and organization, within the 250-bp terminal sequences there are three regions that are conserved in both sequence and position suggesting they are under functional constraint. Nucleotide sequence data from this article have been deposited in the EMBL/GenBank databases with the accession numbers: AM493769, AM493770, AM493771, AM493772.  相似文献   

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The subtidal brown algal species Sporochnus dotyi Brostoff (Sporochnales, Phaeophyceae), which has been regarded as a Hawaiian endemic, is reported from Kushimoto, Kii Peninsula, Pacific coast of central Honshu, Japan, for the first time outside Hawai'i. The species grew on subtidal rocks ca. 5–20 m deep attached by a small conical holdfast. The erect thalli were 5–30 cm high, terete, robust and alternately branched in 1–2 orders. When mature, pedicellate receptacles developed on the branches, and formed elliptical sori 1 mm long with a pedicel 3–5 mm long. The apical parts of the thalli and the receptacles were terminated with a tuft of simple assimilatory filaments of up to 4 mm long and showed prominent green to yellow underwater iridescence. Reproductive filaments (paraphyses) were densely packed, simple, up to 200 μm long and bore 4–6 mostly unilateral unilocular zoidangia 20–22 μm long and 5–6 m in diameter. In the genetic analyses, the Sporochnus alga from Kushimoto had partial rbcL sequence identical to S. dotyi from Hawai'i. The cox3 phylogeny revealed that this alga formed a fully supported clade with S. dotyi. Therefore, we identified the alga from Kushimoto as S. dotyi. This finding of S. dotyi from Japan, together with the recent reports of the mesophotic macroalgae Ryuguphycus kuaweuweu (=Umbraulva kuaweuweu), Ulva iliohaha and Newhousia imbricata from various localities in the Pacific Ocean including Japan, suggest closer biogeographical connections of subtidal/mesophotic macroalgae in the Pacific than previously recognized.  相似文献   

19.
Hierochloe quebrada, Anthoxanthinae, Aveneae, Poaceae, of steep, tropicalpine granitic ravines in northern Peru is described as new; plants had formerly been referred to H. juncifolia but differ from that southern South American species especially in a shorter lemma with long white ascending marginal hairs, and the lemma of the middle floret with a compound awn inserted mid-point, with a long, brown, twisting colum bearing, inflexed or reflexed, a straw-coloured, straight, equally long arista; the flat leaf-blade is deeply grooved adaxially with simple furrows, and lacks a prominent midrib; ecologically H. quebrada on steep tropicalpine granitic soils to 4600 m is in contrast to H. juncifolia of temperate southern latitudes on volcanic, stony, or sandy soils to about 1750 m. Monoecism is exclusive to all species of Hierochloe in South America; pathways towards its evolution are outlined.  相似文献   

20.
The genome of Lactococcus lactis encodes a single long chain 3-ketoacyl-acyl carrier protein synthase. This is in contrast to its close relative, Enterococcus faecalis, and to Escherichia coli, both of which have two such enzymes. In E. faecalis and E. coli, one of the two long chain synthases (FabO and FabB, respectively) has a role in unsaturated fatty acid synthesis that cannot be satisfied by FabF, the other long chain synthase. Since L. lactis has only a single long chain 3-ketoacyl-acyl carrier protein synthase (annotated as FabF), it seemed likely that this enzyme must function both in unsaturated fatty acid synthesis and in elongation of short chain acyl carrier protein substrates to the C18 fatty acids found in the cellular phospholipids. We report that this is the case. Expression of L. lactis FabF can functionally replace both FabB and FabF in E. coli, although it does not restore thermal regulation of phospholipid fatty acid composition to E. coli fabF mutant strains. The lack of thermal regulation was predictable because wild-type L. lactis was found not to show any significant change in fatty acid composition with growth temperature. We also report that overproduction of L. lactis FabF allows growth of an L. lactis mutant strain that lacks the FabH short chain 3-ketoacyl-acyl carrier protein synthase. The strain tested was a derivative (called the ∆fabH bypass strain) of the original fabH deletion strain that had acquired the ability to grow when supplemented with octanoate. Upon introduction of a FabF overexpression plasmid into this strain, growth proceeded normally in the absence of fatty acid supplementation. Moreover, this strain had a normal rate of fatty acid synthesis and a normal fatty acid composition. Both the ∆fabH bypass strain that overproduced FabF and the wild type strain incorporated much less exogenous octanoate into long chain phospholipid fatty acids than did the ∆fabH bypass strain. Incorporation of octanoate and decanoate labeled with deuterium showed that these acids were incorporated intact as the distal methyl and methylene groups of the long chain fatty acids.  相似文献   

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