共查询到12条相似文献,搜索用时 93 毫秒
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本文对缘毛鹅观草(Roegneria pendulina)、鹅观草(R.tsukushiensis var.transiens)及其人工合成杂种F_1、双二倍体进行了细胞学,育性等的分析和研究。结果表明双亲的减数分裂,花粉育性和结实性均正常,杂种F_1的减数分裂不规则且完全不育;当代双二倍体的染色体数目为70,其减数分裂构型为:6.04 Ⅰ+26.21 Ⅱ+1.52 Ⅲ+1.59 Ⅳ+0.02 Ⅴ:第二代双二倍体的染色体数目为70,个别植株为69,减数分裂构型分别为:4.16 Ⅰ+27.33 Ⅱ+0.50 Ⅲ+2.16 Ⅳ和4.79 Ⅰ26.26 Ⅱ+1.13 Ⅲ+2.13 Ⅳ。与期望染色体配对模式相比,双二倍体中二价体出现的频率有明显增大的趋势。在减数分裂AⅠ和AⅡ分别观察到数目不定的落后单价体,大部份的四分体中出现了微核。双二倍体的育性得到了很大程度的恢复,其花粉可染色性及结实率分别为54.4%和64.0%。 相似文献
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2n雄配子的无融合生殖披碱草(Elymus rectisetus)减数分裂行为研究 总被引:1,自引:0,他引:1
用能自然产生2n雄配子的无融合生殖六倍体披碱草为材料,研究了无融合生殖披碱草的减数分裂行为。结果表明:2n雄配子的无融合生殖披碱草减数分裂行为较为异常。在间期细胞内经常有微核存在;在前期I,有倒位环、多介染色体等异常现象;在中期I,染色体有不等分裂的倾向;在后期I和末期I,有染色体的单极分裂(63.9%)、染色走向一极的倾向(21.7%)和多极分裂(3.3%)等现象,单极分裂的结果是不减数配子的产生。在减数分裂Ⅱ中,有高比例的二分子孢子(55.7%)和三分子孢子(23.7%)的形成,二分子孢子在发育后期也直接导致了2n配子的产生。因此,染色体的单极分裂、二分体和三分体形成这3种方式是披碱草2n雄配子的形成的主要途径。 相似文献
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长穗偃麦草酸性磷酸酶与碱性磷酸酶编码基因的染色体定位 总被引:4,自引:0,他引:4
以一套中国春-长穗偃麦草二体异附加系与二体异代换系为材料,用等电聚焦(IEF)研究长穗偃麦草基因组中酸性磷酸酶(AcPh)与碱性磷酸酶(APH)编码基因的染色体定位。结果表明,AcPh大多聚焦于pH5~7范围内,其编码基因位于3E染色体,而APH编码基因则位于4E染色体。由于5E染色体的附加,AcPh活性带强度显著减弱。 相似文献
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SONG FangZhou CHANG PingAn ZHANG PingBo YI FaPing MA YongPing LU Cheng
Yutaka BANNO & Hiroshi FUJII
《中国科学:生命科学英文版》2008,51(2):133-139
Yutaka BANNO & Hiroshi FUJII
《中国科学:生命科学英文版》2008,51(2):133-139
The chromosomal locations of two single-copy genes, Ser-1 and CI-13, in silkworm (Bombyx mori) were detected at the molecular cytogenetics level by fluorescence in situ hybridization in the study. The results showed that Ser-1 is located near the distal end of the 11th linkage group, relatively at the 12.5±1.4 position in pachytene; and that CI-13 has been mapped near the distal end of the 2nd linkage group, relatively at the 8.2±1.2 position in pachytene. Furthermore, their location model map-FISH map on silkworm chromosome was drawn. The FISH technique and its application to silkworm are also discussed in this paper. 相似文献
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病害问题是制约我国扇贝养殖业发展的关键, 因此贝类的先天免疫也成为当前研究的热点。丝氨酸蛋白酶是先天免疫中至关重要的酶类,在许多通路中起信号放大作用。目前对栉孔扇贝丝氨酸蛋白酶的研究主要集中于基因序列分析和表达谱研究, 基因定位方面的研究尚未开展。文章以包含一种栉孔扇贝丝氨酸蛋白酶基因的BAC克隆为探针, 利用BAC-FISH技术将其定位到一对同源染色体的长臂上, 为丝氨酸蛋白酶基因的后续研究提供了基础; 同时, 利用PCR产物直接测序法筛选了该基因内部的6个SNP标记, 这些SNP标记可供遗传图谱定位使用, 从而可以实现遗传图谱与染色体间的锚定与初步整合 相似文献
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异育淇鲫及其双亲同工酶的比较研究 总被引:14,自引:0,他引:14
用4.5%聚丙烯酰胺凝胶平板电泳研究了异育淇鲫及其母本淇鲫和父本兴国红鲤的肌可溶性蛋白以及肾、肝、眼、背白肌和心等五种组织的乳酸脱氢酶(LDH)、苹果酸脱氢酶(MDH)和酯酶(EST)。结果发现:异育淇鲫的肌可溶性蛋白以及同工酶的电泳图谱与母本淇鲫相同而与父本兴国红鲤显著不同,因而认为异育淇鲫是淇鲫雌核发育的产物,父本基因对子代基本无影响。在此基础上,本文对异源精子在雌核发育中所起的生物学作用进行了初步探讨。 相似文献
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The binding modes of the [Ru(II)(1,10-phenanthroline)(L1L2) dipyrido[3,2-a:2′,3′-c]phenazine]2+ {[Ru(phen)(py) Cl dppz]+ (L1 = Cl, L2 = pyridine) and ([Ru(phen)(py)2dppz]2+ (L1 = L2 = pyridine)} to native DNA is compared to that of the [Ru(II)(1,10-phenanthroline)2dipyrido[3,2-a:2′,3′-c]phenazine]2+ complex ([Ru(phen)2dppz]2+) by various spectroscopic and hydrodynamic methods including electric absorption, linear dichroism (LD), fluorescence spectroscopy, and viscometric titration. All measured properties, including red-shift and hypochromism in the dppz absorption band, nearly perpendicular molecular plane of the dppz ligand with respect to the local DNA helix axis, prohibition of the ethidium binding, the light switch effect and binding stoichiometry, increase in the viscosity upon binding to DNA, increase in the melting temperature are in agreement with classical intercalation of dppz ligand of the [Ru(phen)2dppz]2+ complex, in which both phenanthroline ligand anchored to the DNA phosphate groups by electrostatic interaction. [Ru(phen)(py)2 dppz]2+ and [Ru(phen)(py) Cl dppz]+ complexes had one of the phenanthroline ligand replaced by either two pyridine ligands or one pyridine plus a chlorine ion. They exhibited similar protection from water molecules, interaction with DNA bases, and occupying site that is common with ethidium. The dppz ligand of these two Ru(II) complex were greatly tilted relative to the DNA helix axis, suggesting that the dppz ligand resides inside the DNA and is not perpendicular relative to the DNA helix axis. These observation suggest that anchoring the [Ru(phen)2dppz]2+complex by both phenanthroline is essential for the dppz ligand to be classically intercalated between DNA base-pairs. 相似文献
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Meiotic metaphases II from archival slides were studied of male house mice caught in a hybrid zone between a population monomorphic
for nine centric fusions (2n = 22) and a population with the standard karyotype (2n = 40), near Rome. The frequency of aneuploidy
increases, up to 50%, with increasing number of heterozygous centric fusions (1–4).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Visual verification of close disposition between a rice A genome-specific DNA sequence (TrsA) and the telomere sequence 总被引:2,自引:0,他引:2
A rice A genome-specific tandem repeat sequence (TrsA) and telomeric nucleotide sequences, (TTTAGGG)n, were simultaneously detected by multicolor fluorescence in situ hybridization (McFISH) using rice prometaphase chromosomes. Six pairs of TrsA sites visualized by fluorescence signals were all localized on the long arms close to the telomeric regions. Differences in the copy number of TrsA at the different sites were visualized both by the size of the telomeric condensation block stained with Giemsa solution and the signal intensity after FISH with TrsA. McFISH analyses using interphase nuclei could resolve close disposition of TrsA and telomere and also gave rough estimation of the distance between them. The functional significance of the close disposition of TrsA and telomere is discussed. 相似文献