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Sphaerellothecium stereocaulorum sp. nov., Stigmidium beringicum sp. nov., Stigmidium stereocaulorum sp. nov. and goniocysts are described on Stereocaulon species from the northern Holarctic. Endococcus nanellus is reported new to Alaska and Mongolia. Taxonomical novelties Sphaerellothecium stereocaulorum Zhurb. & Triebel, Stigmidium beringicum Zhurb. & Triebel, Stigmidium stereocaulorum Zhurb. & Triebel.  相似文献   

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Summary  Three new species are described in Barleria L. sect. Stellatohirta M. Balkwill from tropical Africa: B. aristata from south-central Tanzania, B. aenea from south-western Tanzania and northeast Zambia, and B. purpureotincta from south-western Zambia. Their affinities and conservation status are discussed.  相似文献   

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The osteology of Florenciella lugubris is described. F. lugubris is attributed to the family Epigonidae on the basis of specific characters of structure of orbital bones, skull, jaws and hyoid, presence of three principal spines on operculum, contact of pterygiophores of dorsal fins, 10 + 15 vertebrae, extension of the lateral line onto the caudal fin, structure of the first hemapophysis and interhaemale, caudal skeleton, etc. At the same time, Florenciella is more advanced in comparison with Epigonus having such characters as presence of enlarged, directed to sides and/or forward symphyseal teeth in jaws, of finely and densely denticulatd edges of infraorbitalia 2–8 and of the orbiral edge of frontale, and fontanelle in bulla otica and having specific traits of denticulation of opercular bones, having no separated distal element in the free pterygiophore between the first and second dorsal fins, having modified scales, etc. The related genera Florenciella and Rosenblattia may be synonyms.  相似文献   

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Background

Gonadotropin releasing hormone (GnRH) is responsible for stimulation of gonadotropic hormone (GtH) in the hypothalamus-pituitary-gonadal axis (HPG). The regulatory mechanisms responsible for brain specificity make the promoter attractive for in silico analysis and reporter gene studies in zebrafish (Danio rerio).

Results

We have characterized a zebrafish [Trp7, Leu8] or salmon (s) GnRH variant, gnrh 3. The gene includes a 1.6 Kb upstream regulatory region and displays the conserved structure of 4 exons and 3 introns, as seen in other species. An in silico defined enhancer at -976 in the zebrafish promoter, containing adjacent binding sites for Oct-1, CREB and Sp1, was predicted in 2 mammalian and 5 teleost GnRH promoters. Reporter gene studies confirmed the importance of this enhancer for cell specific expression in zebrafish. Interestingly the promoter of human GnRH-I, known as mammalian GnRH (mGnRH), was shown capable of driving cell specific reporter gene expression in transgenic zebrafish.

Conclusions

The characterized zebrafish Gnrh3 decapeptide exhibits complete homology to the Atlantic salmon (Salmo salar) GnRH-III variant. In silico analysis of mammalian and teleost GnRH promoters revealed a conserved enhancer possessing binding sites for Oct-1, CREB and Sp1. Transgenic and transient reporter gene expression in zebrafish larvae, confirmed the importance of the in silico defined zebrafish enhancer at -976. The capability of the human GnRH-I promoter of directing cell specific reporter gene expression in zebrafish supports orthology between GnRH-I and GnRH-III.
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Summary   Erythroxylum longisetulosum I. Loiola & M. F. Sales and E. timothei I. Loiola & M. F. Sales (sect. Rhabdophyllum) from north-eastern Brazil are described and illustrated, and their taxonomic and ecological relationships are discussed.  相似文献   

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Summary   Typhonium stigmatilobatum V. D. Nguyen, a new species from Vietnam, is described and illustrated.  相似文献   

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Lin X  Minamisawa N  Takechi K  Zhang W  Sato H  Takio S  Tsukaya H  Takano H 《Planta》2008,228(4):601-608
ANGUSTIFOLIA (AN), a plant homolog of C-terminal binding protein, controls the polar elongation of leaf cells and the trichome-branching pattern in Arabidopsis thaliana. In the present study, degenerate PCR was used to isolate an ortholog of AN, referred to as LgAN, from larch (Larix gmelinii). The LgAN cDNA is predicted to encode a protein of 646 amino acids that shows striking sequence similarity to AN proteins from other plants. The predicted amino acid sequence has a conserved NAD-dependent 2-hydroxy acid dehydrogenase (D2-HDH) motif and a plant AN-specific LxCxE/D motif at its N-terminus, as well as a plant-specific long C-terminal region. The LgAN gene is a single-copy gene that is expressed in all larch tissues. Expression of the LgAN cDNA rescued the leaf width and trichome-branching pattern defects in the angustifolia-1 (an-1) mutant of Arabidopsis, showing that the LgAN gene has effects complementary to those of AN. These results suggest that the LgAN gene has the same function as the AN gene.  相似文献   

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Previously, we described the unique feature of telomeric regions in Iberian shrew Sorex granarius: its telomeres have two ranges of size, very small (3.8 kb of telomeric repeats on average) and very large discontinuous telomeres (213 kb) interrupted with 18S rDNA. In this study, we have demonstrated extraordinary replication pattern of S. granarius large telomeres that have not been shown before in other studied mammal. Using the ReD-FISH procedure, we observed prolonged, through S period, large telomere replication. Furthermore, revealed ReD-FISH asymmetric signals were probably caused by partial replication of telomeres within an hour of 5-bromodeoxyuridine treatment due to the large size and special organization. We also found that in contrast to the telomeric halo from primary fibroblasts of bovine, mink, and common shrew, telomere halo of S. granarius consists of multiple loops bundled together, some of which contain rDNA. Here, we suggested several replicons firing possibly stochastic in each large telomere. Finally, we performed the TIF assay to reveal DNA damage responses at the telomeres, and along with TIF in nuclei, we found large bodies of telomeric DNA and ?-H2AX in the cytoplasm and on the surface of fibroblasts. We discuss the possibility of additional origin activation together with recombination-dependent replication pathways, mainly homologous recombination including BIR for replication fork stagnation overcoming and further S. granarius large telomere replication.  相似文献   

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Summary   Calathea dryadica and Calathea reginae are described, circumscribed and illustrated. These new species are probably endemic to the Atlantic Forest of Rio de Janeiro State in Southeast Brazil and are considered critically endangered because of the restricted geographic area of occurrence, sometimes enclosed by densely urbanised areas.  相似文献   

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 Two biological types of Japanese dark chub, so-called types A and B of Zacco temminckii, were taxonomically inspected. A comparison of types A and B with the lectotypes of Leuciscus sieboldii and L. temminckii in Siebold's collection revealed that type A is identical to L. sieboldii, whereas type B matches L. temminckii. Hence, Zacco sieboldii and Z. temminckii were redescribed on the basis of the lectotype and additional specimens from Japan. Zacco sieboldii is distinguishable from Z. temminckii by having a narrower band on the anterior portion of both body sides, nine branched rays of anal fin (10 in Z. temminckii), lateral line scales not less than 53 (not more than 52 in Z. temminckii), and scales above lateral line not less than 13 (not more than 11 in Z. temmincki). A key to the species of Japanese Zacco is also provided. Received: August 15, 1999 / Revised: July 25, 2002 / Accepted: August 19, 2002 Acknowledgments We express our cordial thanks to all the following investigators: Dr. M.J.P. Van Oijen (RMNH) for the specimen loan of von Siebold's collection; Professor San-Rin Jeon, Sang-Myung University (formerly, Seoul) for providing several papers on Korean Zacco congeners; Dr. Harumi Sakai, National Fisheries University; Dr. Tetsuo Furukawa-Tanaka, Museum of Nature and Human Activities, Hyogo; Dr. Seishi Kimura, Mie University; Dr. Akihisa Iwata, Kyoto University; Dr. Osamu Katano, National Research Institute of Fisheries Sciences; Mr. Kazuo Hoshino, Oita Marine Palace; and Dr. Kouichi Kawamura, National Research Institute of Aquaculture, for the valuable comments and information on the ecological aspects of both species of the Japanese dark chub. Correspondence to:Kazumi Hosoya  相似文献   

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Elaphoglossum mickeliorum, a new species from the eastern slopes of the Peruvian Andes, is here described and illustrated. It belongs to E. sect. Polytrichia, which is characterized by the presence of subulate scales and absence of hydathodes on the sterile leaves of adult sporophytes. Herbarium specimens of this new species were first collected by Alwyn H. Gentry ca. 40 years ago, but these got readily confused with E. erinaceum and went undescribed since then. The new species differs from members of the E. erinaceum complex by having a nearly continuous band of planar, nonsubulate scales along the laminar margins of sterile leaves. Based on this character, E. mickeliorum resembles species such as E. glaziovii, E. ornatum, and E. scolopendrifolium. It differs from these by the presence of minute glandular hairs on petioles and costae. A distribution map and a figure with line drawings are also provided. For comparative purposes, the line drawing includes E. blepharoglottis, which is here illustrated for the first time.  相似文献   

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A synthetic chimeric gene SbtCryIII(A) encoding the insecticidal protein btCryIII(A), was transformed into Pinus armandii embryos and embryogenic calli using Agrobacterium tumefaciens. Polymerase chain reaction and genomic DNA Southern blot analysis showed that the SbtCryIII(A) gene was integrated into the genome of transgenic Pinus armandii plants, and Northern blot analysis indicated that the SbtCryIII(A) gene was transcribed.  相似文献   

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Plants have evolved several defense mechanisms, including resistance genes. Resistance to the root-knot nematode Meloidogyne incognita has been found in wild plant species. The molecular basis for this resistance has been best studied in the wild tomato Solanum peruvianum and it is based on a single dominant gene, Mi-1.2, which is found in a cluster of seven genes. This nematode attacks fiercely several crops, including potatoes. The genomic arrangement, number of copies, function and evolution of Mi-1 homologs in potatoes remain unknown. In this study, we analyzed partial genome sequences of the cultivated potato species S. tuberosum and S. phureja and identified 59 Mi-1 homologs. Mi-1 homologs in S. tuberosum seem to be arranged in clusters and located on chromosome 6 of the potato genome. Previous studies have suggested that Mi-1 genes in tomato evolved rapidly by frequent sequence exchanges among gene copies within the same cluster, losing orthologous relationships. In contrast, Mi-1 homologs from cultivated potato species (S. tuberosum and S. phureja) seem to have evolved by a birth-and-death process, in which genes evolve mostly by mutations and interallelic recombinations in addition to sequence exchanges.  相似文献   

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T. Oda  C. Tanaka  M. Tsuda 《Mycoscience》2002,43(1):0081-0083
Amanita concentrica sp. nov. is described from an evergreen broad-leaved forest of Chiba Prefecture with Castanopsis cuspidata var. sieboldii and Quercus glauca. The fungus is a medium to large, white to yellowish-white mushroom characterized by many pyramidal warts on pileus, striate margin of pileus, distinct ascending concen-tric rings at upper part of stipe bulb, and inamyloid basidiospores. It is considered to belong to the section Amanita. Received: March 30, 2001 / Accepted: October 1, 2001  相似文献   

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