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1.
S-Glycoproteins (S-locus-specific glycoproteins) in Brassicaspecies are present only in stigmas and thought to play an importantrole in self-incompatibility system. The stigma extract containsalso several other glycoproteins reacting with the antiserumto S-glycoproteins, among which some glycoproteins from S8S8-and S9S9-homozygotes have the same pI value. Both of the glycoproteinswhich were tentatively termed NS8- and NS8S9-glycoproteins,respectively, were isolated and analyzed. Those were revealedto be identical. Its amino acid sequence was homologous withthe S-glycoproteins in Brassica species. The NS-glycoproteinswere expressed at the same time and only in stigma as S-glycoproteins. (Received July 19, 1988; Accepted September 7, 1988)  相似文献   

2.
3.
Oxley  David; Bacic  Antony 《Glycobiology》1995,5(5):517-523
Gametophytic self-incompatibility, a mechanism that preventsinbreeding in some families of flowering plants, is mediatedby the products of a single genetic locus, the S-locus. Theproducts of the S-gene in the female sexual tissues of Nicotianaalata are an allelic series of glycoproteins with RNase activity.In this study, we report on the microheterogeneity of N-linkedglycosylation at the four potential N-glycosylation sites ofthe S2-glycoprotein. The S-glycoproteins from N.alata containfrom one to five potential N-glycosylation sites based on theconsensus sequence Asn-Xaa-Ser/Thr. The S2-glycoprotein containsfour potential N-glycosylation sites at Asn27, Asn37, Asn138and Asn150, designated sites I, n, IV and V, respectively. SiteIII is absent from the S2-glycoprotein. Analysis of glycopeptidesgenerated from the S2-glycoprotein by trypsin and chymotrypsindigestions revealed the types of glycans and the degree of microheterogeneitypresent at each site. Sites I (Asn27) and IV (Asn138) displaymicroheterogeneity, site II (Asn37) contains only a single typeof N-glycan, and site V (Asn150) is not glycosylated. The microheterogeneityobserved at site I on the S2-glycoprotein is the same as thatobserved at the only site, site I, on the Srglycoprotein (Woodwardet al., Glycobiology, 2, 241-250, 1992). Since the N-glycosylationconsensus sequence at site I is conserved in all S-glycoproteinsfrom other species of self-incompatible solanaceous plants,glycosylation at this site may be important to their function.No other post-translational modifications (e.g. O-glycosylation,phosphorylation) were detected on the S2-glycoprotein. fertilization microheterogeneity N-glycans plants RNase  相似文献   

4.
Single intact pollen grains of Oenothera organensis, when placedupon a thin layer of agar containing pollen antiserum, producecircular areas of precipitate. Pollen grains from an S2S2 plantdo not produce precipitate in S6 antiserum. Pollen grains froman S6S6 plant and an S2'S4' self-compatible plant produce precipitatesin S6 antiserum. Fifty per cent of the pollen grains from anS2S6 plant produce precipitate in S6 antiserum. Protein diffusesinto buffer solutions from intact pollen grains within 212 min.As much as 40 per cent of the total protein diffuses out inan hour. Amylase and invertase were detected in the diffusatefrom pollen grains. Alkaline and acid phosphatases were confinedto the pollen grains and did not diffuse out. The serologicalprecipitates are specific to the incompatibility system.  相似文献   

5.
Stylar proteins of 13 almond (Prunus dulcis) cultivars withknown S-genotypes were surveyed by IEF and 2D-PAGE combinedwith immunoblot and N-terminal amino acid sequence analysesto identify S-RNases associated with gametophytic self-incompatibility(SI) in this plant species. RNase activities corresponding toSa and Sb, two of the four S-alleles tested, were identifiedby IEF and RNase activity staining. The Sa-RNase band reactedwith the anti-S4serum prepared from Japanese pear (Pyrus serotina);no reaction with the antiserum was observed with the sbRNaseband. When the sa-RNase band was excised from an IEF gel stainedfor RNase activity, subjected to SDS-PAGE, and detected by immunoblotting,it appeared that this band consisted of a single protein thatreacted with the anti-s4serum with Mr of about 28 kDa. With2D-PAGE and silver staining of the stylar extracts, all fourS-proteins could be successfully distinguished from each otherin the highly basic zone of the gel. Although Sb-, Sc-, andSdproteins had roughly the same Mr of about 30 kDa, the Sc-proteinseemed to be slightly smaller than the Sb-protein and slightlylarger than the Saprotein. In 2D-PAGE profiles as well, theSa-protein had Mr of about 28 kDa, apparently smaller than theother three proteins. A bud sport, in which one of the two S-allelesof the original cultivar is impaired, was visualized as a lossof Scprotein, which is consistent with the previous pollinationstudy. All four S-proteins reacted with the anti-S4serum, probablybecause of the differing conformations of these S-proteins inthe IEF and 2D-PAGE gels. The Sa-protein in 2D-PAGE appearedto be identical to Sa-RNase in IEF; both bad the same Mr andwere reactive with the anti-S4-serum. N-terminal amino acidsequence analysis of the four 5-proteins revealed that theywere highly homologous to each other and similar to the 5-RNasesof Malus, Pyrus, Scrophulariaceae, and Solanaceae. Taken together,RNases in the style are strongly suggested to be associatedwith the gametophytic SI of al- mond. This is the first reportidentofiying and characterizing S-RNase in almond. (Received July 11, 1996; Accepted December 26, 1996)  相似文献   

6.
Proteolytic fragments were obtained by limited proteolysis of120 kDa nitrate reductase from Spinacia oleracea L. using trypsinand Staphylococcus aureus V8 protease. Determination of NH2-terminalsequences in 9 to 14 Edman degradation steps allowed the exactlocalization of the fragments within the amino-acid sequenceof spinach nitrate reductase was deduced from the nucleotidesequence of cDNA clone pSPNR117 which was initially identifiedby hybridization to squash nitrate reductase cDNA clone [Crawford,1N. M., Campbell, W. H. and Davis, R. W. (1986) Proc. Natl. Acad.Sci. USA 83: 8073] and anti spinach nitrate reductase polyclonalantibodies. This clone has a 2324 base insert, and the aminoacid sequence deduced from its open reading frame, which contains640 residues. The predicted sizes 42.5 and 30 kDa were in reasonableagreement with previous determination of the apparent molecularsizes of the FAD-cyt-chrome b557-binding, and FAD-binding fragments,respectively. Arginine residue was the cleavage site for trypsin and glutamicacid was for S. aureus V8 protease. The amino acid residueswithin the linker regions which connect the functional domains,could be cleaved with trypsin or S. aureus V8 protease may bewell conserved in the amino acid sequences deduced from thenitrate reductase cDNA sequences. A sequence identity of 61.2-80.1 % was found in the amino acidsequences deduced from the cDNA sequences as obtained by spinachand other higher plant nitrate reductases. However, the aminoacid sequences surrounding the proteolytic cleavage sites ofnitrate reductase had poor homology. (Received March 30, 1991; Accepted July 24, 1991)  相似文献   

7.
Reproductive Allometry in Soybean, Maize and Sunflower   总被引:4,自引:2,他引:2  
We compared the relationship between grain yield per plant (YP)and shoot biomass per plant (SP) in three annual crops withcontrasting reproductive strategies: sunflower, a determinatespecies with a single inflorescence; maize, a determinate specieswith a limited capacity to adjust the number of ears in responseto resource availability; and indeterminate soybean, a specieswith a large capacity to adjust the number of inflorescences.Our working hypotheses were: H1—the relationship betweenYPandSP is linear; H2—the intercept of the model is zero,i.e. there is not a threshold plant mass for reproduction. Awide range of YPand SPwas generated by manipulation of plantdensity;SPvaried between 0.3 and 196 g per plant in soybean,between 6 and 873 g per plant in sunflower and between 23 and697 g per plant in maize. Within these broad ranges of plantsize, both hypotheses were rejected in five out of six experiments,i.e. the relationship between YPand SPdeparted from linearityand there was a threshold for SPbelow which no grain set occurred.TheSP threshold for grain set varied widely among species; itwas close to 2 g per plant for soybean, 27 g per plant for sunflowerand 43–71 g per plant for maize. Because of this sizethreshold and non-linearity, harvest index (HI = YPSP-1) wasstable for mid-size plants, diminished slightly for large plants,and diminished sharply for smaller plants in all three crops.Harvest index stability was highest in soybean, intermediatein sunflower and lowest in maize. Differential stability ofreproductive partitioning partially derived from contrastingpatterns of meristem allocation. Copyright 2000 Annals of BotanyCompany Helianthus annuus L., Zea mays L., Glycine max(L.) Merrill, grain yield, harvest index, plant density, reproductive allocation, meristem allocation, plasticity  相似文献   

8.
Phylogenetic reconstruction based upon multiple alignments ofmolecular sequences is important to most branches of modernbiology and is central to molecular evolution. Understandingthe historical relationships among macromolecules depends uponcomputer programs that implement a variety of analytical methods.Because it is impossible to know those historical relationshipswith certainty, assessment of the accuracy of methods and theprograms that implement them requires the use of programs thatrealistically simulate the evolution of DNA sequences. EvolveAGene3 is a realistic coding sequence simulation program that separatesmutation from selection and allows the user to set selectionconditions, including variable regions of selection intensitywithin the sequence and variation in intensity of selectionover branches. Variation includes base substitutions, insertions,and deletions. To the best of my knowledge, it is the only programavailable that simulates the evolution of intact coding sequences.Output includes the true tree and true alignments of the resultingcoding sequence and corresponding protein sequences. A log filereports the frequencies of each kind of base substitution, theratio of transition to transversion substitutions, the ratioof indel to base substitution mutations, and the numbers ofsilent and amino acid replacement mutations. The realism ofthe data sets has been assessed by comparing the dN/dS ratio,the ratio of transition to transversion substitutions, and theratio of indel to base substitution mutations of the simulateddata sets with those parameters of real data sets from the "goldstandard" BaliBase collection of structural alignments. Resultsshow that the data sets produced by EvolveAGene 3 are very similarto real data sets, and EvolveAGene 3 is therefore a realisticsimulation program that can be used to evaluate a variety ofprograms and methods in molecular evolution.  相似文献   

9.
A summary of recent work on molecular aspects of self-incompatibility in Nicotiana alata is presented. The amino acid sequences of style proteins corresponding to different S-alleles of N. alata have a high level of homology in some regions and are variable in other regions. The regions of homology include N-terminal sequences as well as most of the glycosylation sites and cysteine residues. The glycosyl substituents may consist of a number of glycoforms. The isolated style S-glycoproteins inhibit in vitro growth of pollen tubes. The S-glycoproteins tested inhibited the growth of pollen of several S-genotypes, and there was some specificity in the interaction. Heat treatment of the isolated S-glycoproteins dramatically increased their activity as inhibitors of pollen tube growth, although the specificity in the interaction was lost. The nature of the S-allele products in pollen is not yet established.  相似文献   

10.
Yellow prisms of asparagusic acid, with a molecular formulaof C4H6O2S2 were isolated from etiolated asparagus tissues (Asparagusofficinalis L.). This acid inhibits growth in lettuce and otherseedlings when applied in concentrations of 6.67x10–7Mto 6.67xl0–7M. The extent of activity was very similarto that of abscisic acid. 1 A well known shift reagent in the NMR spectrum (1). (Received April 12, 1972; )  相似文献   

11.
Japanese pear (Pyrus serotina Rehd.) exhibits gametophytic self-incompatibility. Following our previous findings that basic ribonucleases in the styles of Japanese pear are associated with self-incompatibility genes (S-RNases), stylar proteins with high pI values were analyzed by two-dimensional gel electrophoresis further to characterize S-RNases. A group of basic proteins of about 30 kDa associated with self-incompatibility genes were identified. These proteins contained sugar chains which reacted with concanavalin A and wheat germ agglutinin, and thus were designated as S-glycoproteins of Japanese pear. The fact that the S-glycoprotein was expressed at a much lower level in a self-compatible mutant than in the original variety suggested a role of S-glycoproteins in mediating self-incompatibility of Japanese pear. Immunoblot analysis indicated that S-glycoproteins are identical to previously identified S-RNases. The S-glycoproteins were predominantly expressed in the style, in the ovary in trace amounts, and not in leaf, pollen or germinated pollen. The N-terminal amino acid sequences of the S-glycoproteins showed homology not only with each other but also with those of the S-allele-associated proteins from plants of the family Solanaceae at levels of about 30–50%.  相似文献   

12.
13.
采用自行设计式及仿制圆筒式诱捕器,以人工合成性信息素(Z,E)-9,12-tetradecadienyl acetate (简称TDA) 为引诱源在实验室条件下对影响诱捕器诱捕印度谷螟Plodia interpunctella效果的几个因素进行分析测定。多元线性回归分析结果表明:日平均温度在18.5~26.2℃,人工合成性信息素TDA散发日数9~37天,温度(X1)、TDA散发日数(X2)、当日释放蛾(雄)量(X3)、累计2日释放蛾量(X4)、累计3日释放蛾量(X5)等5个因素与每日诱捕蛾量间存在着相关关系。对5个因素进行逐步回归分析和筛选,得出线性回归方程:Y=-27.31+1.37X1+0.28X3,回归系数R(0.90)>R0.01(n-2,0.63)。统计分析结果表明:日平均温度(X1)、当日释放蛾量(X3)与诱蛾量(Y)之间呈显著线性相关关系。卡方测验表明预测值与实测值之间差异不显著。  相似文献   

14.
冯姗  张耀洲 《昆虫学报》2006,49(5):726-732
锌带蛋白(zinc ribbon protein )是锌指类蛋白的一种,它的Cys4 Zn(2+)结合位点由3个β2片层折叠而成,而不是α螺旋结构。锌带结构与锌指结构同为转录因子结合核酸的结构域,锌带蛋白作为转录相关因子在调节基因表达活性等方面具有重要作用。在对家蚕 Bombyx mori蛹cDNA文库测序中,发现一个新的编码家蚕锌带蛋白基因的EST序列(GenBank 登录号DY230964),以此序列为信息探针检索家蚕EST数据库,通过同源筛选,获得一个新的家蚕锌带蛋白基因cDNA全序列并经RT-PCR检测和克隆、测序验证,结果表明与电子克隆序列完全一致。我们将其命名为 BmZNRD1 (Zinc Ribbon Domain Containing 1)(GenBank登录号DQ432055)。该基因全长为675 bp,由363 bp的开放阅读框序列(ORF)、10 bp的5′端非翻译区序列(5′UTR)和302 bp 的3′端非编码区序列(3′ UTR)组成,其编码的120个氨基酸序列与其他真核生物间具有较高的同源性(达60%左右),预测分子量为13.54 kD, 等电点为6.8。BmZNRD1编码的氨基酸序列是一种锌带蛋白,推测有2个功能结构域,分别是位于N-端的Cx2Cx14Cx2C和C-端的Cx2Cx24Cx2C,其中C-端保守氨基酸序列Cx2Cx6Yx3QxRSADEx2TxFx2Cx2C在生物进化中保守性很高,从酵母、果蝇、线虫到两栖类、哺乳类都有发现该结构域的存在,与酵母RNA聚合酶A亚单位9和转录相关蛋白有很高的相似性,推测其具有相同的功能。将BmZNRD1基因cDNA序列与家蚕基因组序列进行比对,结果表明该基因具有3个外显子,2个内含子,外显子/内含子边界符合经典的GT-AG规则。 关键词: 家蚕; 锌带蛋白基因; 电子克隆; 基因克隆; 序列分析  相似文献   

15.
K2S2O8, applied to the basal end of cuttings of Vigna radiatastimulated leaf abscission in the light or dark. Because inhibitionof leaf sbscission in the dark by IAA was completely abolishedby K2S2O8, and IAA decreased stimulation of abscission by K2S2O8,destruction of IAA in the cuttings by K2S2O8 is indicated. K2S2O8had no effect on leaf abscission when applied as a foliar sprayor when roots of undisturbed seedlings were treated. When appliedproximally or distally to leafless explants, K2S2O8 inhibitedpetiole abscission, and neither IAA nor ethylene had an effecton the inhibition. Although K2S2O8 destroyed IAA in vitro, ithad no effect on abscission inhibitors in macerates of Vignaleaves and corn roots, nor did it destroy the biological activityof IAA added to such macerates. Substances liberated by macerationmay interfere with the ability of K2S2O8 to destroy IAA. (Received May 2, 1981; Accepted August 24, 1981)  相似文献   

16.
A survey of Solanum chacoense plants expressing an authenticS11-RNase transgene identified a line with partial compatibilityto S11 pollen. By comparing fruit set to the S-RNase levelsdetermined immunologically in single styles, the minimum levelof S11-RNase required for full rejection of S11 pollen was estimatedto be 18 ng per style. The S11-RNase threshold levels are thusconsiderably lower than those previously reported for the S12-RNase.Interestingly, these two allelic S-RNases differ dramaticallyin the extent of glycosylation, with the number of glycosylationsites varying from one (S11-RNase) to four (S12-RNase). It issuggested that reduced glycosylation of the S11-RNase may berelated to the lower threshold for pollen rejection. Key words: Gametophytic self-incompatibility, glycosylation, pistil-by-pistil analysis, S-RNase, Solanum chacoense, threshold Received 13 August 2007; Revised 27 November 2007 Accepted 30 November 2007  相似文献   

17.
Owing to a typographical error three equations were omittedfrom page 1294. The correct paragraphs are set out below. The component K1 corrected for the difference in temperaturebetween the enzyme assay and the leaf and was calculated accordingto the Arrhemus equation. where v10 and v18 are the reaction velocities of carboxylationat 10?C and 18?C, respectively and A is the activation energy(A = 90 kJ mol–1, as determined for purified wheat RuBPCOby M?chler, Keys and Cornelius, 1980) The components K2 corrected for the difference in CO2 partialpressure between enzyme assay and leaf and for competitive inhibitionof carboxylation by O2 and was calculated according to the modifiedMichaelis Menten equation where vc, is the carboxylation velocity under leaf conditions,Vc. is the maximum carboxylation velocity as determined in theenzyme assay, Kc, and Ko are the Michaelis constants for carboxylationand oxygenation, respectively (Ko = 159 Pa CO2. Ko = 35.3 kPaO2, as interpolated for 18?C from spinach data as determinedby Jordan and Ogren, 1984), O is oxygen partial pressure inair and C1 is intercellular CO2 partial pressure in leaves (C1= 29.1 ? 0.8 Pa (? s c , n = 15)) The component K3 corrected for the decrease in CO2 fixationin leaves due to photorespiration and was calculated accordingto equation 3 Equation 3 is denved from the equation for the substrate specificityof RuBPCO, S= vc/voC (Laing, Ogren, and Hageman, 1974), andfrom the equation for the stoichiometry of photorespiratoryCO2 release, F=vc–1/2 vo, where vc, and vc are reactionvelocities of carboxylation and oxygenation, O and C are partialpressures of 02 and intercellular CO2, F is net photosynthesisand S is the substrate specificity of RuBPCO (S= 3061 Pa/Pa,as interpolated for 18?C from spinach data as determined byJordan and Ogren, 1984)  相似文献   

18.
Six proteins, designated SAP1 through SAP6, were secreted specificallyby salt-adapted cells of winged bean (Psophocarpus tetragonolobus)in suspension cultures. The amino-terminal amino acid sequencesof SAP2 (57 kDa), SAP4 (21 kDa), SAP5 (19 kDa) and SAP6 (17kDa) were homologous to the sequences of proline-rich proteins,indicating that proline-rich proteins are secreted specificallyby these salt-adapted cells. In addition, the amino-terminalamino acid sequence of SAP2 was identical to that of SAP4, andthe amino-terminal sequence of SAP5 was identical to that ofSAP6. Secretion of SAP2 was significantly enhanced by additionof AlCl3 but not of KCl, LiCl, CaCl2, MgCl2, mannnitol or sucroseto suspension cultures. Furthermore, secretion of SAP4, SAP5and SAP6 was stimulated by addition of abscisic acid to cultures,suggesting that these proteins might be secreted in responseto salt or osmotic stress. (Received September 12, 1994; Accepted January 20, 1995)  相似文献   

19.
Excitation of characean cells was studied in experiments usinga voltage-clamp. The efflux of monovalent anion was estimatedfrom the inward current (J1) and was compared with that measuredby the conductometry method (J8). It was found that, on theaverage, J1 was larger than J8 in Nitella. The Ca2+ influx isdiscussed with a view to explaining the discrepancy betweenJ1 and J8. (Received April 27, 1987; Accepted August 26, 1987)  相似文献   

20.
The ultrastructure of papillar cells of Brassica campestrison the day of anthesis was studied by the liquid helium rapid-freezingand a substitution-fixation method, abbreviated as the RFS method.Application of the RFS method to the analysis of papillar cellsenabled us to examine clear images of these cells which havenot been observed previously. The well-developed rough and smoothendoplasmic reticulum, numerous Golgi bodies and mitochondria,various small vesicles and clathrin-coated vesicles, were presentin the cells. The numbers of Golgi bodies, as well as the numbersof cisternae of each Golgi body, increased as compared to thatin the other cells of style. Lattice-like fenestrated and flattenedcisternae were seen adjacent to the narrowest trans cisternaof the Golgi body, which had a partially coated region at itsperiphery. Many coated vesicles were observed in the vicinityof this structure and the plasma membrane. Coated areas on theplasma membrane were also observed. The ultrastructure of papillarcells on the day of anthesis indicated that they are very activesecretory cells. By using an antibody against S8-protein andsections prepared by the RFS method, we demonstrated the distributionof S8-protein in the cell wall of papillar cells of homozygousplants of Brassica campestris SgS8. (Received June 26, 1990; Accepted September 29, 1990)  相似文献   

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