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81.
Chunfa Tong Huogen Li Ying Wang Xuran Li Jiajia Ou Deyuan Wang Houxi Xu Chao Ma Xianye Lang Guangxin Liu Bo Zhang Jisen Shi 《PloS one》2016,11(3)
Although numerous linkage maps have been constructed in the genus Populus, they are typically sparse and thus have limited applications due to low throughput of traditional molecular markers. Restriction-site associated DNA sequencing (RADSeq) technology allows us to identify a large number of single nucleotide polymorphisms (SNP) across genomes of many individuals in a fast and cost-effective way, and makes it possible to construct high-density genetic linkage maps. We performed RADSeq for 299 progeny and their two parents in an F1 hybrid population generated by crossing the female Populus deltoides ‘I-69’ and male Populus simonii ‘L3’. A total of 2,545 high quality SNP markers were obtained and two parent-specific linkage maps were constructed. The female genetic map contained 1601 SNPs and 20 linkage groups, spanning 4,249.12 cM of the genome with an average distance of 2.69 cM between adjacent markers, while the male map consisted of 940 SNPs and also 20 linkage groups with a total length of 3,816.24 cM and an average marker interval distance of 4.15 cM. Finally, our analysis revealed that synteny and collinearity are highly conserved between the parental linkage maps and the reference genome of P. trichocarpa. We demonstrated that RAD sequencing is a powerful technique capable of rapidly generating a large number of SNPs for constructing genetic maps in outbred forest trees. The high-quality linkage maps constructed here provided reliable genetic resources to facilitate locating quantitative trait loci (QTLs) that control growth and wood quality traits in the hybrid population. 相似文献
82.
H. Thorsten Lumbsch Thomas Lunke G. Benno Feige Siegfried Huneck 《Plant Systematics and Evolution》1995,198(3-4):275-286
The anatomy, chemistry and developmental morphology ofAnamylopsora pulcherrima is investigated. Some characters, including the ascus structure, suggest a close affinity with theAgyriaceae. However, the chemistry and the pycnidial structure differ as well as the ascoma ontogeny.Anamylopsora has a gymnocarpous ascoma development and the ascogonia are produced in stipes.Trapelia coarctata, as a typical member of theAgyriaceae, shows a hemiangiocarpous ascoma ontogeny. The anatomical, chemical and ontogenetical characters of several families are compared withAnamylopsora and it is shown that the genus is best placed in a monotypic familyAnamylopsoraceae
Lumbsch & Lunke, fam. nova, which is placed in theAgyriineae (Lecanorales).This paper is dedicated to Prof. DrAino Henssen (Marburg) on the occasion of the 70th birthday. 相似文献
83.
Augusto C. Franco Angela Haag-Kerwer Britta Herzog Thorsten E. E. Grams Erika Ball Eduardo A. de Mattos Fabio R. Scarano Suzanne Barreto Maria A. Garcia Andre Mantovani Ulrich Lüttge 《Trees - Structure and Function》1996,10(6):359-365
Sandy plains are characteristic of the coastal region of Brazil. We investigated the diel patterns of changes in organic acid levels, leaf conductance and chlorophylla fluorescence for sun-exposed and shaded plants ofClusia hilariana, one of the dominant woody species in the sandy coastal plains of northern Rio de Janeiro state. Both exposed and shaded plants showed a typical CAM pattern with considerable diel oscillations in organic acid levels. The degradation of both malic and citric acids during the midday stomatal closure period could lead to potential CO2 fixation rates of 28 mol m-2 s-1 in exposed leaves. Moreover, exposed leaves exhibited large increases in total non-photochemical quenching (qN) accompanied by a substantial decrease in effective quantum yield during the course of the day. However, these potential high rates of CO2 fixation and the increases inqn of exposed plants were not enough to maintain the primary electron acceptor of photosystem II (qA) in a low reduction state, similar to that of shaded plants. As a result, there was a moderate increase in the reduction state of qA throughout the day. Most of the decline in photochemical efficiency of exposed leaves ofC. hilariana was reversible, as evidenced by the high levels of pre-dawn potential quantum yields (Fv/Fm) and their rapid recovery after sunset. However, the depletion of the organic acid pool in the afternoon resulted in an accentuated subsequent drop in Fv/Fm, suggesting that prolonged periods of water stress accompanied by high irradiance levels may expose plants ofC. hilariana in unprotected habitats to the danger of photoinhibition. 相似文献
84.
85.
Racemic analogues of platelet-activating factor and its lyso derivatives have been prepared in which one methyl of the trimethylammonium group has been replaced by ethyl, propyl, allyl, or carboxymethylene. The influence of chemical modification on the biological activity was assessed by measuring platelet aggregation and desensitization. The results point to a crucial role of a positively charged polar head group for the expression of biological activity of platelet-activating factor. There are also some indications of a more non-specific interaction of the polar head group of platelet-activating factor with its platelet binding sites. 相似文献
86.
Dcp from Escherichia coli is a 680 residue cytoplasmic peptidase, which shows a strict dipeptidyl carboxypeptidase activity. Although Dcp had been assigned to the angiotensin I-converting enzymes (ACE) due to blockage by typical ACE inhibitors, it is currently grouped into the M3 family of mono zinc peptidases, which also contains the endopeptidases neurolysin and thimet oligopeptidase (TOP). We have cloned, expressed, purified, and crystallized Dcp in the presence of an octapeptide "inhibitor", and have determined its 2.0A crystal structure using MAD methods. The analysis revealed that Dcp consists of two half shell-like subdomains, which enclose an almost closed two-chamber cavity. In this cavity, two dipeptide products presumably generated by Dcp cleavage of the octapeptide bind to the thermolysin-like active site fixed to side-chains, which are provided by both subdomains. In particular, an Arg side-chain backed by a Glu residue, together with two Tyr phenolic groups provide a charged anchor for fixing the C-terminal carboxylate group of the P2' residue of a bound substrate, explaining the strict dipeptidyl carboxypeptidase specificity of Dcp. Tetrapeptidic substrates are fixed only via their main-chain functions from P2 to P2', suggesting a broad residue specificity for Dcp. Both subdomains exhibit very similar chain folds as the equivalent but abducted subdomains of neurolysin and TOP. Therefore, this "product-bound" Dcp structure seems to represent the inhibitor/substrate-bound "closed" form of the M3 peptidases, generated from the free "open" substrate-accessible form by a hinge-bending mechanism. A similar mechanism has recently been demonstrated experimentally for ACE2. 相似文献
87.
Short-term dynamics of bacterial communities in a tidally affected coastal ecosystem 总被引:2,自引:0,他引:2
Rink B Martens T Fischer D Lemke A Grossart HP Simon M Brinkhoff T 《FEMS microbiology ecology》2008,66(2):306-319
Tidal effects on the composition of free-living (FL) and particle-associated (PA) bacterial communities were studied in a tidal flat ecosystem in the southern North Sea. Denaturing gradient gel electrophoresis targeting the 16S rRNA gene and the 16S rRNA of Bacteria, Bacteroidetes, Alphaproteobacteria and the Roseobacter clade was applied. Despite strong tidal variations in the quantity and, depending on the season, also the quality of suspended matter as well as variations in bacterial activity, the bacterial community composition remained rather stable. FISH showed some variations of the community composition, but these were not related to typical tidal situations. Variations were higher during tidal cycles in May and July compared with November. Bacteroidetes, Alpha- and Gammaproteobacteria constituted the majority of the bacterial communities but relative proportions of the different groups varied considerably. On particles, Betaproteobacteria were also detected to substantial proportions. The Roseobacter clade constituted up to 90% of FL but only 30% of PA Alphaproteobacteria. Banding patterns of the Bacteroidetes-specific amplicons, and in particular those targeting the 16S rRNA, revealed tidally induced effects, as several bands appeared or disappeared at distinct events such as slack water or resuspension. Sequencing of prominent bands revealed predominantly phylotypes reported previously from this ecosystem. 相似文献
88.
89.
Urschel S Höher T Schubert T Alev C Söhl G Wörsdörfer P Asahara T Dermietzel R Weiler R Willecke K 《The Journal of biological chemistry》2006,281(44):33163-33171
Gap junctions in AII amacrine cells of mammalian retina participate in the coordination of the rod and cone signaling pathway involved in visual adaptation. Upon stimulation by light, released dopamine binds to D(1) receptors on AII amacrine cells leading to increased intracellular cAMP (cyclic adenosine monophosphate) levels. AII amacrine cells express the gap junctional protein connexin36 (Cx36). Phosphorylation of Cx36 has been hypothesized to regulate gap junctional activity of AII amacrine cells. However, until now in vivo phosphorylation of Cx36 has not been reported. Indeed, it had been concluded that Cx36 in bovine retina is not phosphorylated, but in vitro phosphorylation for Cx35, the bass ortholog of Cx36, had been shown. To clarify this experimental discrepancy, we examined protein kinase A (PKA)-induced phosphorylation of Cx36 in mouse retina as a possible mechanism to modulate the extent of gap junctional coupling. The cytoplasmic domains of Cx36 and the total Cx36 protein were phosphorylated in vitro by PKA. Mass spectroscopy revealed that all four possible PKA consensus motifs were phosphorylated; however, domains point mutated at the sites in question showed a prevalent usage of Ser-110 and Ser-293. Additionally, we demonstrated that Cx36 was phosphorylated in cultured mouse retina. Furthermore, activation of PKA increased the level of phosphorylation of Cx36. cAMP-stimulated, PKA-mediated phosphorylation of Cx36 protein was accompanied by a decrease of tracer coupling between AII amacrine cells. Our results link increased phosphorylation of Cx36 to down-regulation of permeability through gap junction channels mediating light adaptation in the retina. 相似文献
90.
Binzhi Qian Yan Deng Jae Hong Im Ruth J. Muschel Yiyu Zou Jiufeng Li Richard A. Lang Jeffrey W. Pollard 《PloS one》2009,4(8)