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21.
金线莲外植体筛选及愈伤组织诱导研究 总被引:2,自引:0,他引:2
以金线莲茎段、叶片、茎片、不定芽为试材,分别在添加6-BA、ZT、NAA、KT 5个不同处理的MS及1/2MS培养基上培养,诱导愈伤组织。结果表明,以茎段、茎片、不定芽为外植体,在MS + 6-BA 2.0 mg/L + NAA0.5 mg/L、MS + NAA 2.0 mg/L + KT 0.1 mg/L和MS + 6-BA 2.0 mg/L + NAA 0.5 mg/L + ZT 0.2 mg/L培养基中培养,均能成功诱导愈伤组织。不定芽为诱导愈伤组织最佳外植体,最佳培养基为MS + 6-BA 2.0 mg/L + NAA 0.5 mg/L + KT 0.2 mg/L。 相似文献
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Peter M. Bourke Paul Arens Roeland E. Voorrips G. Danny Esselink Carole F. S. Koning‐Boucoiran Wendy P. C. van't Westende Tiago Santos Leonardo Patrick Wissink Chaozhi Zheng Geert van Geest Richard G. F. Visser Frans. A. Krens Marinus J. M. Smulders Chris Maliepaard 《The Plant journal : for cell and molecular biology》2017,90(2):330-343
It has long been recognised that polyploid species do not always neatly fall into the categories of auto‐ or allopolyploid, leading to the term ‘segmental allopolyploid’ to describe everything in between. The meiotic behaviour of such intermediate species is not fully understood, nor is there consensus as to how to model their inheritance patterns. In this study we used a tetraploid cut rose (Rosa hybrida) population, genotyped using the 68K WagRhSNP array, to construct an ultra‐high‐density linkage map of all homologous chromosomes using methods previously developed for autotetraploids. Using the predicted bivalent configurations in this population we quantified differences in pairing behaviour among and along homologous chromosomes, leading us to correct our estimates of recombination frequency to account for this behaviour. This resulted in the re‐mapping of 25 695 SNP markers across all homologues of the seven rose chromosomes, tailored to the pairing behaviour of each chromosome in each parent. We confirmed the inferred differences in pairing behaviour among chromosomes by examining repulsion‐phase linkage estimates, which also carry information about preferential pairing and recombination. Currently, the closest sequenced relative to rose is Fragaria vesca. Aligning the integrated ultra‐dense rose map with the strawberry genome sequence provided a detailed picture of the synteny, confirming overall co‐linearity but also revealing new genomic rearrangements. Our results suggest that pairing affinities may vary along chromosome arms, which broadens our current understanding of segmental allopolyploidy. 相似文献
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蔷薇种子的休眠及解除方法 总被引:3,自引:0,他引:3
分析了蔷薇(Rosa L.)种子休眠原因、解除休眠方法以及环境条件对休眠与萌发的影响.蔷薇种子休眠的主要原因有瘦果果皮和种皮的限制作用,胚生理休眠以及果肉、瘦果果皮、种皮和胚中的抑制物质.解除休眠的方法包括去除瘦果果皮限制、解除胚的生理休眠、去除抑制物质等.种子发育过程中及成熟后,环境因子,如温度、水分和光照,对种子休眠和萌发有影响.此外,微生物、果实采集时间也对种子休眠及萌发有较大影响.蔷薇种子的休眠机制复杂,且种间差异很大. 相似文献
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Petri Itäranta Keijo Viiri Vesa Kaartinen Seppo Vainio 《Differentiation; research in biological diversity》2009
Neural crest (NC) cells may be involved in kidney organogenesis by providing inductive signals and contributing to cells of the renal stroma. We show here that the lumbo-sacral NC cells fate mapped with the aid of Wnt-1 promoter in the mouse migrate close to the metanephros at the initiation of organogenesis but these cells remain superficial to the condensed Pax2-expressing mesenchymal cells. NC-derived cells enter later into the kidney proper from the midline region. The NC cells contribute also to development of the extra-adrenal para-aortic bodies, Zuckerkandl's bodies and the nerve cord of the sympathetic nervous system. Splotch (Sp2H/Sp2H) embryos, having a NC defect in the lumbo-sacral region, develop a normal metanephros even though the kidney does not express the NC markers Sox10, Phox2b and tyrosine hydroxylase. Consistent with the histological findings, the kidneys of Sp2H/Sp2H embryos also express the stromal genes Foxd1, Hoxa10 and RARβ normally. Wnt-1 promoter-marked wild-type LacZ NC cells migrate intensely from the heterologous inducer tissue of the embryonic dorsal spinal cord (SPC) to the kidney mesenchyme, but tubule induction does not depend on NC migration, since the Sp2H/Sp2H SPC also induces tubulogenesis. The Sp2H/Sp2H mesenchyme also remains competent for tubulogenesis. We conclude that the NC cells fate mapped with the aid of Wnt-1 promoter migrate to the close to the metanephros and form later derivatives integrating with the kidney, but they may not be essential to the development of the stromal cells nor they may provide critical morphogenetic signals to regulate early kidney development in vivo. 相似文献
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Dimitra Chormova David J. Messenger Stephen C. Fry 《The Plant journal : for cell and molecular biology》2014,77(4):534-546
The cell‐wall pectic domain rhamnogalacturonan‐II (RG‐II) is cross‐linked via borate diester bridges, which influence the expansion, thickness and porosity of the wall. Previously, little was known about the mechanism or subcellular site of this cross‐linking. Using polyacrylamide gel electrophoresis (PAGE) to separate monomeric from dimeric (boron‐bridged) RG‐II, we confirmed that Pb2+ promotes H3BO3‐dependent dimerisation in vitro. H3BO3 concentrations as high as 50 mm did not prevent cross‐linking. For in‐vivo experiments, we successfully cultured ‘Paul's Scarlet’ rose (Rosa sp.) cells in boron‐free medium: their wall‐bound pectin contained monomeric RG‐II domains but no detectable dimers. Thus pectins containing RG‐II domains can be held in the wall other than via boron bridges. Re‐addition of H3BO3 to 3.3 μm triggered a gradual appearance of RG‐II dimer over 24 h but without detectable loss of existing monomers, suggesting that only newly synthesised RG‐II was amenable to boron bridging. In agreement with this, Rosa cultures whose polysaccharide biosynthetic machinery had been compromised (by carbon starvation, respiratory inhibitors, anaerobiosis, freezing or boiling) lost the ability to generate RG‐II dimers. We conclude that RG‐II normally becomes boron‐bridged during synthesis or secretion but not post‐secretion. Supporting this conclusion, exogenous [3H]RG‐II was neither dimerised in the medium nor cross‐linked to existing wall‐associated RG‐II domains when added to Rosa cultures. In conclusion, in cultured Rosa cells RG‐II domains have a brief window of opportunity for boron‐bridging intraprotoplasmically or during secretion, but secretion into the apoplast is a point of no return beyond which additional boron‐bridging does not readily occur. 相似文献
30.
Boron (B) is essential for plant cell‐wall structure and membrane functions. Compared with its role in cross‐linking the pectic domain rhamnogalacturonan II (RG‐II), little information is known about the biological role of B in membranes. Here, we investigated the involvement of glycosylinositol phosphorylceramides (GIPCs), major components of lipid rafts, in the membrane requirement for B. Using thin‐layer chromatography and mass spectrometry, we first characterized GIPCs from Rosa cell culture. The major GIPC has one hexose residue, one hexuronic acid residue, inositol phosphate, and a ceramide moiety with a C18 trihydroxylated mono‐unsaturated long‐chain base and a C24 monohydroxylated saturated fatty acid. Disrupting B bridging (by B starvation in vivo or by treatment with cold dilute HCl or with excess borate in vitro) enhanced the GIPCs' extractability. As RG‐II is the main B‐binding site in plants, we investigated whether it could form a B‐centred complex with GIPCs. Using high‐voltage paper electrophoresis, we showed that addition of GIPCs decreased the electrophoretic mobility of radiolabelled RG‐II, suggesting formation of a GIPC–B–RG‐II complex. Last, using polyacrylamide gel electrophoresis, we showed that added GIPCs facilitate RG‐II dimerization in vitro. We conclude that B plays a structural role in the plasma membrane. The disruption of membrane components by high borate may account for the phytotoxicity of excess B. Moreover, the in‐vitro formation of a GIPC–B–RG‐II complex gives the first molecular explanation of the wall–membrane attachment sites observed in vivo. Finally, our results suggest a role for GIPCs in the RG‐II dimerization process. 相似文献