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The authorship of Platycephalus japonicus and Platycephalus crocodilus is researched. Although many authors have considered that the authorship of these flatheads can be attributed to Tilesius (1812), we consider that Cuvier in Cuvier and Valenciennes [ex Tilesius] (1829) has valid authorship of them. Platycephalus isacanthus, Platycephalus borboniensis and Platycephalus guttatus were also established by Cuvier in the same publication. The conspecificity of these three species and the precedence of P. japonicus are reconfirmed in this study. Although many authors have recognized the validity of P. guttatus, its holotype is identical to P. crocodilus. We also establish the precedence of P. crocodilus over P. guttatus.  相似文献   

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The class B genes, which belong to the MADS-box gene family, play important roles in regulating petal and stamen development in flowering plants. These genes exist in two different types termed DEF- and GLO-like genes, and the B-function is provided by heterodimers of a DEF- and a GLO-like gene product. In the present study, dicot (tobacco and lettuce) and monocot (Tricyrtis hirta) plants were transformed with the GLO-like gene of Agapanthus praecox ssp. orientalis ApGLO alone or in combination with the DEF-like gene of the same plant ApDEF. In two out of 10 transgenic tobacco plants containing ApGLO, sepals partially converted into petaloid organs. For lettuce, ray florets of four out of nine transgenic plants containing ApGLO also developed additional petaloid organs. In two out of five transgenic T. hirta plants containing both ApGLO and ApDEF, organs developed in whorl 4 showed noticeable morphological alteration: they were much longer compared with carpels of non-transgenic plants, and had purple spots overall on the surface as filaments of non-transgenic plants. No morphological alterations were observed in vegetative organs between transgenic and non-transgenic plants for all the three species. The results obtained in the present study indicate a possibility of molecular breeding for flower form alteration by genetic transformation with the class B MADS-box gene(s) of heterologous plant species.  相似文献   

4.
In the classical taxonomy, three Scomber species are distinguished: S. scombrus, S. australasicus, and S. japonicus. Yet, some fish taxonomists have recently recognized Scomber colias, inhabiting the Atlantic Ocean, as a separate species from S. japonicus, distributed in the Pacific Ocean. Such proposal was based on significant mitochondrial DNA divergence as well as great phenotypic variation among individuals from these two ocean basins. However, in the absence of nuclear DNA data this issue remains still controversial. In this study, a phylogenetic analysis of nuclear 5S rDNA sequences was performed. A total of 30 individuals of S. colias collected in the Atlantic and 34 specimens of S. japonicus from the Pacific were characterized. Moreover, nine individuals of Pacific S. australasicus and eight of Atlantic S. scombrus were included. Maximum likelihood, maximum parsimony, and neighbor-joining analyses revealed the presence of two well-supported distinct clades corresponding to S. colias and S. japonicus, respectively. Altogether, morphologic and genetic data are in agreement with the recognition of two different species, S. colias in the Atlantic, and S. japonicus in the Pacific.  相似文献   

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The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

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Carotenoids represent a group of valuable molecules for the pharmaceutical, chemical, food and feed industries, not only because they can act as vitamin A precursors, but also for their coloring, antioxidant and possible tumor-inhibiting activity. Animals cannot synthesize carotenoids, and these pigments must therefore be added to the feeds of farmed species. The synthesis of different natural commercially important carotenoids (β-carotene, torulene, torularhodin and astaxanthin) by several yeast species belonging to the genera Rhodotorula and Phaffia has led to consider these microorganisms as a potential pigment sources. In this review, we discuss the biosynthesis, factors affecting carotenogenesis in Rhodotorula and Phaffia strains, strategies for improving the production properties of the strains and directions for potential utility of carotenoid-synthesizing yeast as a alternative source of natural carotenoid pigments.  相似文献   

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The wobbegong genus Orectolobus occurring from Japan and its adjacent waters was reviewed, and O. japonicus was redescribed using ten specimens including a syntype. Only one species, O. japonicus, was regarded as valid among three species previously recorded from Japan. Orectolobus maculatus had been erroneously described from Japan because of the past nomenclatural confusion with O. japonicus. The specimen called “Karakusa-oose,” which had been identified with O. ornatus, was regarded as an irregular form of O. japonicus. Orectolobus japonicus was distinguished from the other congeners by having no tubercles on the body, five to eight dermal lobes in the preorbital group, two distally notched lobes in the postspiracular group, no dermal lobes on lower jaw, nasal barbel with a branch, no supraocular knob, relatively high dorsal fins with usually concave posterior margins, a lower number of precaudal vertebrae and intestinal valve turns, saddles on the back without black borders and yellowish and variously shaped blotches, not forming white O-shaped spots.  相似文献   

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Seol E  Jung Y  Lee J  Cho C  Kim T  Rhee Y  Lee S 《Plant cell reports》2008,27(7):1197-1206
Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.  相似文献   

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P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

10.
Cháb D  Kolár J  Olson MS  Storchová H 《Planta》2008,228(6):929-940
FLOWERING LOCUS T (FT) like genes are crucial regulators (both positive and negative) of flowering in angiosperms. We identified two FT homologs in Chenopodium rubrum, a short-day species used as a model plant for the studies of photoperiodic flower induction. We found that CrFTL1 gene was highly inducible by a 12-h dark period, which in turn induced flowering. On the other hand, photoperiodic treatments that did not induce flowering (short dark periods, or a permissive darkness interrupted by a night break) caused only a slight increase in CrFTL1 mRNA level. We demonstrated diurnal oscillation of CrFTL1 expression with peaks in the middle of a light period. The oscillation persisted under constant darkness. Unlike FT homologs in rice and Pharbitis, the CrFTL1 expression under constant darkness was very low. The CrFTL2 gene showed constitutive expression. We suggest that the CrFTL1 gene may play a role as a floral regulator, but the function of CrFTL2 remains unknown.  相似文献   

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We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan.  相似文献   

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Pisum sativum L., the garden pea crop plant, is serving as the unique model for genetic analyses of morphogenetic development of stipule, the lateral organ formed on either side of the junction of leafblade petiole and stem at nodes. The stipule reduced (st) and cochleata (coch) stipule mutations and afila (af), tendril-less (tl), multifoliate-pinna (mfp) and unifoliata-tendrilled acacia (uni-tac) leafblade mutations were variously combined and the recombinant genotypes were quantitatively phenotyped for stipule morphology at both vegetative and reproductive nodes. The observations suggest a role of master regulator to COCH in stipule development. COCH is essential for initiation, growth and development of stipule, represses the UNI-TAC, AF, TL and MFP led leafblade-like morphogenetic pathway for compound stipule and together with ST mediates the developmental pathway for peltate-shaped simple wild-type stipule. It is also shown that stipule is an autonomous lateral organ, like a leafblade and secondary inflorescence.  相似文献   

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A pea rust fungus, Uromyces viciae-fabae, has been classified into two varieties, var. viciae-fabae and var. orobi, based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of urediniospores and teliospores of 94 rust specimens from Vicia, Lathyrus, and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia, Lathyrus, and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae-fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum. These results suggest that U. viciae-fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.Contribution no. 184, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

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Bacterial ssrA encodes tmRNA that functions both as a tRNA and an mRNA to rescue the stalled ribosome on defective mRNAs. In this study, ssrA was identified in four gastric species of Helicobacters and four enterohepatic species of Helicobacters. The tag peptide of 14 amino acids encoded by ssrA showed a pattern of Val(1)Ala(13) in gastric species, a pattern of Ala(1)Val(13 )in enterohepatic species, in contrast to the pattern of Ala(1)Ala(13) in W. succinogenes and C. jejuni, which are closely related to helicobacters. Phylogenetic analysis and the patterns of the tag peptide suggest that the Helicobacter genus could be separated into two genera. High conservation of ssrA in H. pylori was observed. The annotated ORF HP0784 in H. pylori, which largely overlaps ssrA, is unlikely to be functional. H. pylori ssrA interestingly expressed a large and a small tmRNA molecule.  相似文献   

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Genome sequence analysis of Xanthomonas oryzae pv. oryzae has revealed a cluster of 12 ORFs that are closely related to the gum gene cluster of Xanthomonas campestris pv. campestris. The gum gene cluster of X. oryzae encodes proteins involved in xanthan production; however, there is little experimental evidence supporting this. In this study, biochemical analyses of xanthan produced by a defined set of X. oryzae gum mutant strains allowed us to preliminarily assign functions to most of the gum gene products: biosynthesis of the pentasaccharide repeating unit for GumD, GumM, GumH, GumK, and GumI, xanthan polymerization and transport for GumB, GumC, GumE, and GumJ, and modification of the pentasaccharide repeating unit for GumF, GumG, and GumL. In addition, we found that the exopolysaccharides are essential but not specific for the virulence of X. oryzae. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Sang-Yoon Kim and Jeong-Gu Kim contributed equally to this work.  相似文献   

19.
Chen X  Li Y  Huang J  Cao D  Yang G  Liu W  Lu H  Guo A 《Cell and tissue research》2007,329(1):169-178
The microtubule-binding protein tau has been investigated for its contribution to various neurodegenerative disorders. However, the findings from transgenic studies, using the same tau transgene, vary widely among different laboratories. Here, we have investigated the potential mechanisms underlying tauopathies by comparing Drosophila (d-tau) and human (h-tau) tau in a Drosophila model. Overexpression of a single copy of either tau isoform in the retina results in a similar rough eye phenotype. However, co-expression of Par-1 with d-tau leads to lethality, whereas co-expression of Par-1 with h-tau has little effect on the rough eye phenotype. We have found analogous results by comparing larval proteomes. Through genetic screening and proteomic analysis, we have identified some important potential modifiers and tau-associated proteins. These results suggest that the two tau genes differ significantly. This comparison between species-specific isoforms may help to clarify whether the homologous tau genes are conserved. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. This study was supported by the National Science Foundation of China (30270341; 30630028), the Multidisciplinary Program (Brain and Mind) of the Chinese Academy of Sciences, the Major State Basic Research Program (“973 program”; G2000077800; G2006CB806600; 2006CB911003), the Precedent Project of Important Intersectional Disciplines in the Knowledge Innovation Engineering of the Chinese Academy of Sciences (KJCX1-09-03).  相似文献   

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