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1.
The S-locus glycoprotein gene, SLG, which participates in the pollen-stigma interaction of self-incompatibility, and its unlinked homologue, SLR1, were analyzed in Raphanus sativus and three self-incompatible ornamental plants in the Brassicaceae. Among twenty-nine inbred lines of R. sativus, eighteen S haplotypes were identified on the basis of DNA polymorphisms detected by genomic Southern analysis using Brassica SLG probes. DNA fragments of SLG alleles specifically amplified from eight S haplotypes by PCR with class I SLG-specific primers showed different profiles following polyacrylamide gel electrophoresis, after digestion with a restriction endonuclease. The nucleotide sequences of the DNA fragments of these eight R. sativus SLG alleles were determined. Degrees of similarity of the nucleotide sequences to a Brassica SLG (S? 6 SLG) ranged from 85.6% to 91.9%. Amino acid sequences deduced from these had the twelve conserved cysteine residues and the three hypervariable regions characteristic of Brassica SLGs. Phylogenetic analysis of the SLG sequences from Raphanus and Brassica revealed that the Raphanus SLGs did not form an independent cluster, but were dispersed in the tree, clustering together with Brassica SLGs. These results suggest that diversification of the SLG alleles of Raphanus and Brassica occurred before differentiation of these genera. Although SLR1 sequences from Orychophragmus violaceus were shown to be relatively closely related to Brassica and Raphanus SLR1 sequences, DNA fragments that are highly homologous to the Brassica SLG were not detected in this species. Two other ornamental plants in the Brassicaceae, which are related more distantly to Brassica than Orychophragmus, also lacked sequences highly homologous to Brassica SLG genes. The evolution of self-incompatibility in the Brassicaceae is discussed.  相似文献   

2.
Salt-induced changes in the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and lipid peroxidation in terms of malondialdehyde (MDA), level of H2O2, and some key metabolites such as soluble proteins, free proline and phenolics in the leaves of six radish cultivars (Radish Red Neck, Radish Lal Pari, Radish Mino Japani, Radish 40 Days, Mannu Early and Desi) were investigated. Varying levels of NaCl (0, 80 and 160 mM) applied for 40 days adversely affected the shoot fresh weight, chlorophyll contents and soluble proteins, while increased the levels of proline, and the activities of SOD, POD and CAT. However, leaf H2O2 and total phenolic contents were not affected by salt stress. Cultivars Mannu Early, Radish 40 Days and Desi were relatively higher in shoot fresh weight (percent of control) while cvs. Radish Mino Japani and Mannu Early in proline, and cvs. Radish 40 Days and Desi in total soluble proteins at 160 mM of NaCl. However, levels of H2O2 and phenolics were higher in cvs. Desi, Radish Lal Pari and Mannu Early and SOD, POD and CAT activities only in Radish Lal Pari and Mannu Early than the other cultivars under saline conditions. Overall, the differential salt tolerance of radish cultivars observed in the present study was not found to be associated with higher antioxidant enzyme activities and other key metabolites analyzed, so these attributes cannot be considered as selection criteria for salt tolerance in radish.  相似文献   

3.
赵宽  吴沿友  周葆华 《广西植物》2015,35(2):206-212
以诸葛菜和油菜为材料,水培环境下设置4个不同的缺锌和碳酸氢根离子胁迫处理,分别为+Zn0(含Zn且不加HCO3-的处理组),+Zn10(含Zn且加10 mmol·L-1HCO3-的处理组),-Zn0(缺Zn且不加HCO3-的处理组)和-Zn10(缺Zn且加10 mmol·L-1HCO3-的处理组),利用离子色谱法分析了4个处理的两种植物幼苗器官(根、茎、叶)及根系分泌物中的有机酸特征。结果表明:(1)高浓度碳酸氢根离子处理显著增加了两种植物器官及根系分泌的有机酸总量,尤其是在缺锌和高浓度碳酸氢根离子双重胁迫下(-Zn10处理),诸葛菜器官和根系分泌的有机酸比油菜更敏感,草酸、柠檬酸和苹果酸是诸葛菜器官和根系分泌物中的优势酸,这三种有机酸的含量分别占其有机酸总量的75%及以上;(2)叶片是两种植物有机酸产生的主要器官,有机酸的含量和分配比例从地上部分(叶和茎)到地下部分(根)减少;(3)两种植物器官和根系分泌物中的有机酸变化趋势一致,叶片中有机酸主要来源于暗呼吸过程和光呼吸过程,其他器官和根系分泌物中的有机酸主要来源于暗呼吸过程;(4)诸葛菜对缺锌和高浓度碳酸氢根离子的适应能力强于油菜,为诸葛菜的喀斯特适生性和低锌和高浓度碳酸氢根离子环境(如喀斯特环境)的生态修复提供了理论依据。  相似文献   

4.
Summary Genetic and molecular analysis of the self-incompatibility locus (S-locus) of the crucifer Brassica has led to the characterization of a multigene family involved in pollen-stigma interactions. While the crucifer Arabidopsis thaliana does not have a self-incompatibility system, S-related sequences were detected in this species by cross-hybridization with Brassica DNA probes. In this paper, we show that an A. thaliana S-related sequence, designated AtS1, is expressed specifically in flower buds. Sequence analysis suggests that AtS1 encodes a secreted glycoprotein that is most similar to the Brassica S-locus related protein SLR1. As has been proposed for SLR1, this gene may be involved in determining some fundamental aspect of pollen-stigma interactions during pollination. The molecular and genetic advantages of the Arabidopsis system will provide many avenues for testing this hypothesis.  相似文献   

5.
The direct resolution and quantitation of (R)- and (S)-disopyramide, isolated from human plasma, was accomplished using a chiral α1-acid glycoprotein column. A LiChrosorb RP-2 column (50 × 3.0 mm I.D.) was used as a precolumn. Phosphate buffer, pH 6.20, containing 2-propanol and N,N-dimethyloctylamine was used as mobile phase, expressed as the relative standard deviation, was 1.8% and 3.3% for (R)- and (S)-disopyramide, respectively, at a drug level of 0.5 μg/ml. In two subjects who received a single capsule of racemic disopyramide (150 mg), the plasma levels of the (R) isomer were about half those of the (S) isomer. The half-lives of (R)- and (S)-disopyramide were similar.  相似文献   

6.
该研究以黄瓜“津春2号”cDNA为模板,采用RT PCR方法克隆得到黄瓜叶绿素降解关键酶(pheophorbide a oxygenase,PAO)基因(CsPAO),对其进行亚细胞定位观察,并采用实时荧光定量PCR技术和生物信息学技术,分析了CsPAO基因的表达模式及其编码蛋白的特性。结果表明:(1)CsPAO编码545个氨基酸,理论等电点为6.09,蛋白相对分子质量为61.02 kD。蛋白预测发现,黄瓜CsPAO属于不稳定蛋白,具有2个蛋白结合位点,且存在跨膜现象。(2)荧光定量PCR结果表明,CsPAO基因表达响应水杨酸(SA)、茉莉酸 (JA)和赤霉素(GA3)的调控,在高温(42 ℃)和低温(4 ℃)处理下CsPAO基因的表达量显著上升并达到最高,但黑暗处理对CsPAO基因表达没有影响;在黄瓜不同组织中花的表达显著高于根、茎、叶、萼、须、果。(3)亚细胞定位结果表明,CsPAO蛋白定位于叶绿体内。(4)系统进化树分析显示,黄瓜CsPAO与葫芦科植物苦瓜、西葫芦、南瓜、笋瓜等亲缘关系较近。本研究结果为进一步揭示黄瓜叶绿素降解的分子机制奠定了基础。  相似文献   

7.
以加工型黄瓜材料NW99为对象,利用RT-PCR技术克隆黄瓜多聚半乳糖醛酸酶抑制蛋白基因(PGIP),并分析其基因编码序列、组织表达特异性和诱导表达模式。结果表明:(1)从黄瓜中克隆到一个PGIP基因,命名为CsPGIP;CsPGIP基因全长1 026bp,读码框987bp,无内含子,编码328个氨基酸残基,具有xxLxLxxNxLt/sGxIPxxLxxLxxL结构域,属于Pgip基因家族。(2)CsPGIP基因与甜瓜PGIP基因同源性最高,与十字花科Pgip基因同源性较高。(3)CsPGIP在黄瓜各个器官都表达,但表达水平具有组织特异性,在嫩叶中表达量最高,在茎中表达量最低;该基因表达明显受到水杨酸诱导,可能在抵御外界病原菌入侵过程中起重要作用。  相似文献   

8.
为深入研究绣球属植物花粉形态的分类学价值和系统学意义,厘清绣球属与近缘属之间的系统发育关系,该文利用扫描电子显微镜(SEM,scanning electron microscope)对国产绣球属及其近缘属41种绣球花科(Hydrangeaceae)植物的花粉形态以及表面纹饰进行了观察。结果表明:绣球属及其近缘属的花粉为三孔沟;形状多数为长圆体形或近球体形;赤道面观为椭圆形或圆形;极面观多为圆形,少数为三角形或圆三角形。花粉外壁纹饰可分为网状和孔穴状。网眼内的三级纹饰可分为光滑和具颗粒状突起。根据花粉形状和外壁纹饰类型将上述物种划分为4个组,即花粉的形状为长圆体形,表面纹饰为孔穴纹饰;花粉的形状为长圆体形,表面纹饰为网状纹饰;花粉的形状为近球体形,表面纹饰为孔穴纹饰;花粉的形状为近球体形,表面纹饰为网状纹饰。以上可进一步细分为8个类型。上述表明花粉形态证据可为绣球属及其近缘属的属下分类和种间界定提供重要佐证;但结合前人的系统发育重建分析该属植物花粉形态的系统学意义相对有限,如花粉形态证据对于该属及其近缘种属系统发育树上大支的界定难以提供有力的证据。  相似文献   

9.
Summary An unstable spontaneous mutation in the maize Adh1 gene, coding for alcohol dehydrogenase, was selected by allyl alcohol poisoning of wild type Adh1 pollen from a maize line carrying Ds at the Bz2 locus and one copy of Ac in an unknown position. The mutant has a null phenotype. No wild type pollen grains were detected in strains devoid of Ac, but in the presence of Ac, wild type pollen grains were detected with a frequency of between 10-4 and 10-3. In addition, events have been identified in the aleurone in which reversions of both bz2-m and the unstable adh1 mutation occurred in the same patch of tissue, presumably in response to an alteration of Ac. By these criteria, the Adh1 mutant is caused by Ds. DNA blotting experiments have shown the presence of a 1.3 kb insertion in the Adh1 gene. All or part of this Ds insertion is transcribed, and is detected as an insertion within the ADH1-mRNA. The longer mRNA hybridizes to an authentic Ds probe.This Ds element differs in size from other known Ds insertions.  相似文献   

10.
We have characterized Tdr1, a family of Tc1-like transposable elements found in the genome of zebrafish (Danio rerio). The copy number and distribution of the sequence in the zebrafish genome have been determined, and by these criteria Tdr1 can be classified as a moderately repetitive, interspersed element. Examination of the sequences and structures of several copies of Tdr1 revealed that a particular deletion derivative, 1250 by long, of the transposon has been amplified to become the dominant form of Tdr1. The deletion in these elements encompasses sequences encoding the N-terminal portion of the putative Tdr1 transposase. Sequences corresponding to the deleted region were also detected, and thus allowed prediction of the nucleotide sequence of a hypothetical full-length element. Well conserved segments of Tc1-like transposons were found in the flanking regions of known fish genes, suggesting that these elements have a long evolutionary history in piscine genomes. Tdr1 elements have long, 208 by inverted repeats, with a short DNA motif repeated four times at the termini of the inverted repeats. Although different from that of the prototype C. elegans transposon Tc1, this inverted repeat structure is shared by transposable elements from salmonid fish species and two Drosophila species. We propose that these transposons form a subgroup within the Tc1-like family. Comparison of Tc1-like transposons supports the hypothesis that the transposase genes and their flanking sequences have been shaped by independent evolutionary constraints. Although Tc1-like sequences are present in the genomes of several strains of zebrafish and in salmonid fishes, these sequences are not conserved in the genus Danio, thus raising the possibility that these elements can be exploited for gene tagging and genome mapping.  相似文献   

11.
12.
Results of the flower structure analysis of single mutants abr, ap3-1, and pi-1 and double mutants abr ap3-1 and abr pi-1 of the Arabidopsis thaliana are presented. An increase in the expressivity of the ap3-1 and pi-1 mutations against a background of the abr mutation which break auxin transport was detected. Unlike flowers of parental mutant plants which had stamens in our experiment, stamens were absent in basal flowers of double mutants. It can be assumed that anomalies in auxin distributions in cells can break the program of the development of stamens which is triggered by the ap3-1 and pi-1 alleles remaining the residual function during the plant growing at 21–24°C.  相似文献   

13.
We have mapped the human ORFX gene to chromosome 9q34 and determined its complete gene structure. Comparison with RING3, the human MHC-linked homologue on 6p21.3, shows the two gene structures to be highly conserved but with an approximate threefold expansion in the ORFX introns. RING3 and ORFX are found to be ubiquitously expressed in human adult and foetal tissues. Evidence suggests that the two genes may have arisen from an ancient duplication in a common ancestral chromosome.  相似文献   

14.
Abstract: Phylogenetic relationships and biogeography of 25 Rorippa species were studied using sequences of two non-coding regions of chloroplast DNA ( trn L intron, trnL /F spacer). Our results indicate a close relationship between European ( R. islandica ssp. islandica, R. pyrenaica ) and North American (R. curvipes, R. sinuata) mountain species. The polyploid European lowland species R. amphibia, R. palustris and R. sylvestris are much younger than the mountain species and have their closest relatives in western Asia and Siberia. Different colonization routes of the southern hemisphere are discussed for Rorippa. Australasia was colonized at least twice, most likely via the Malayan route. A molecular clock approach dates the first colonization to the end of Pliocene or early Pleistocene. R. gigantea reached Australia later in the Pleistocene. Our data provide evidence for an amphitropical disjunction between the South American (R. philippiana) and North American (R. curvisiliqua) species. Long-distance dispersal via migrating birds is the most likely explanation for this intercontinental disjunction. Two of the analysed African species (R. nudiuscula, R. madagascariensis) have their closest relative (R. austriaca) in eastern Europe and western Asia. The lack of sequence divergence among these species indicates a colonization event probably not earlier than 100 000 years ago.  相似文献   

15.
Inflorescence and floral ontogeny of the perennial, herbaceous crop Crocus sativus L. were studied using epi-illumination light microscopy. After production of leaves with helical arrangement a determinate inflorescence forms which becomes completely transformed into a single terminal flower. In some cases, bifurcation of the inflorescence meristem yields two or three floral meristems. The order of floral organs initiation is outer tepals – stamens – inner tepals – carpels. Stamens and outer tepals are produced from the lateral bifurcation of three common stamen-tepal primordia. Within each whorl, organs start developing unidirectionally from the adaxial side, except for the stamens which begin to grow from the abaxial side. Specialized features during organ development include interprimordial growth between tepals forming a perianth tube, fusion at the base of stamen filaments, and formation of an inferior ovary with unfused styles.  相似文献   

16.
孙稚颖  李法曾 《广西植物》2009,29(3):296-299
对十字花科葶苈族的辣根属、南芥族的豆瓣菜属及相关属种植物的叶绿体DNA的trnL内含子和trnL-F基因间隔区序列进行了测定分析。结果表明,辣根属植物与南芥族的山芥属、蔊菜属、豆瓣菜属、碎米荠属在系统发育树中聚成一支,与葶苈族的模式属葶苈属植物相隔较远,结合形态特征,本研究认为辣根属应从葶苈族移出,其系统位置应靠近山芥属、蔊菜属、豆瓣菜属、碎米荠属植物;此外,系统发育树中,豆瓣菜属植物并入碎米荠属中,表明二者具有更近的亲缘关系,本研究结果不支持《中国植物志》第33卷对辣根属和豆瓣菜属的系统位置的处理。  相似文献   

17.
The Black Bengal is a prolific goat breed in India. Natural mutations in prolific sheep breeds have shown that the transforming growth factor beta (TGF-β) super family ligands such as growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15) and their type I receptor (bone morphogenetic protein receptor, BMPR1B) are crucial for ovulation and as well as for increasing litter size. Mutations in any of these genes increased prolificacy in sheep. Based on the known mutation information in sheep PCR primers were designed to screen known polymorphism in 88 random Black Bengal goats. Only the BMPR1B gene was polymorphic. Three genotypes of animals were detected in tested animals with mutant (FecBB) and wild type (FecB+) alleles were 0.57 and 0.43, respectively. Non-carrier, heterozygous carrier and homozygous carrier Black Bengal does had 2.7, 3.04 and 3.11 kids, respectively. All known point mutations of BMP15 and GDF9 genes were monomorphic in the animals tested. These results preliminarily showed that the BMPR1B gene might be a major gene that influences prolificacy of Black Bengal goats.  相似文献   

18.
The pyruvate kinase-encoding gene (pki1) from Trichoderma reesei was isolated by hybridization to the corresponding Aspergillus nidulans pkiA gene. The 1614-bp nucleotide (nt) sequence of the cloned gene codes for a 538-amino-acid protein. The coding sequence contains a single intron of 246 nt at a position identical to that of intron E in the A. nidulans gene. The PKI protein shows extensive homology to the PKIs of A. nidulans and A. niger (67%) and Saccharomyces cerevisiae (59%). The 5' non-coding sequence contains a number of motifs typical for yeast glycolytic genes, but so far only rarely found in filamentous fungi.  相似文献   

19.
Glycoproteins secreted by the yeast Kluyveromyces lactis are usually modified by the addition at asparagines-linked glycosylation sites of heterogeneous mannan residues. The secreted glycoproteins in K. lactis that become hypermannosylated will bear a non-human glycosylation pattern and can adversely affect the half-life, tissue distribution and immunogenicity of a therapeutic protein. Here, we describe engineering a K. lactis strain to produce non-hypermannosylated glycoprotein, decreasing the outer-chain mannose residues of N-linked oligosaccharides. We investigated and developed the method of two-step homologous recombination to knockout the OCH1 gene, encoding α1,6-mannosyltransferase and MNN1 gene, which is homologue of Saccharomyces cerevisiae MNN1, encoding a putative α1,3-mannosyltransferase. We found the Kloch1 mutant strain has a defect in hyperglycosylation, inability in adding mannose to the core oligosaccharide. The N-linked oligosaccharides assembled on a secretory glycoprotein, HSA/GM–CSF in Kloch1 mutant, contained oligosaccharide Man13–14GlcNAc2, and in Kloch1 mnn1 mutant, contained oligosaccharide Man9–11GlcNAc2, whereas those in the wild-type strain, consisted of oligosaccharides with heterogeneous sizes, Man>30GlcNAc2. Taken together, these results indicated that KlOch1p plays a key role in the outer-chain mannosylation of N-linked oligosaccharides in K. lactis. The KlMnn1p, was proved to be certain contribution to the outer hypermannosylation, most possibly encodes α1,3-mannosyltransferase. Therefore, the Kloch1 and Kloch1 mnn1 mutants can be used as a foundational host to produce glycoproteins lacking the outer-chain hypermannoses and further maybe applicable to be a promising system for yeast therapeutic protein production.  相似文献   

20.
We have cloned fourNeurospora crassagenes by complementation analysis. Cloned genes include thearginine-1(arg-1),methionine-6(met-6),unknown-7(un-7), andribosome production-1(rip-1) loci. Chromosome walks were initiated in ordered cosmid libraries from the cloned loci. A total of about 700 kb of theNeurosporagenome is covered in these walks.  相似文献   

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