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101.
NAD激酶在光合作用等植物生理过程中起重要作用。NAD激酶的激活依赖于钙离子和钙调素(CalmOdulin,CaM).从植物中分离得到的一种新的CaM结合蛋白CaMBP-10(BP-10)明显抑制NAD激酶的激活活性,抑制作用可被CaM所克服.动力学研究表明,抑制效应是BP-10与CaM之间特异性相互作用的结果。实验证实BP-10对NAD激酶活性起着重要调节作用. 相似文献
102.
G.-L. Wang J.-M. Dong A. H. Paterson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(6-7):1153-1161
Cotton is unusual among major crop plants in that two cross-fertile species are widely cultivated for a common economic product, fiber. Both historical evidence and classical genetic studies suggest that many improved forms of Gossypium barbadense (Sea Island, Egyptian, and Pima cottons) may include chromatin derived from G. hirsutum. Using 106 restriction fragment length polymorphism (RFLP) loci well distributed across the cotton genome, we revealed the amount and genomic distribution of G. hirsutum chromatin in 54 G. barbadense collections from around the world. The average G. barbadense collection was comprised of 8.9% alleles apparently derived from G. hirsutum. Pima cultivars (7.3 %) had fewer G. hirsutum alleles than Sea Island (9.0%) or Egyptian (9.6%) cultivars. G. hirsutum alleles were not randomly distributed, as 57.5% of the total introgression observed was accounted for by five specific chromosomal regions that span less than 10% of the genome. The average length of an introgressed chromosome segment was 12.9 cM. Overlap of introgressed chromatin in different breeding programs hints that retention of these G. hirsutum chromosomal segments may impart a selective advantage to G. barbadense genotypes. Although cluster analysis generally grouped germ plasm from common classes and/or breeding programs together, no 2 genotypes were identical — thus differences in the length and repertoire of introgressed chromosome segments also permit DNA fingerprinting of G. barbadense cultivars. 相似文献
103.
Regulation of cellulase synthesis in mycelial fungi: Participation of ATP and cyclic AMP 总被引:1,自引:0,他引:1
Summary ATP and cAMP in 4 strains of mycelial fungi were determined by luciferin-luciferase system and HPLC respectively. Cellulase synthesis was subject to the dual control of ATP and cAMP. No matter what carbon sourse was used, cellulase synthesis was repressed if intracellular ATP concentration was over 10-7mg/ml. Exogenous cAMP could increase cellulase synthesis under depression conditions. 相似文献
104.
Michael E. Pacold Fred J. Stevens Dong Li Louise E. Anderson 《Photosynthesis research》1995,43(2):125-130
Light activation of NADP-linked glyceraldehyde-3-P dehydrogenase involves reductive cleavage of a disulfide bond. We have proposed that the inactivating disulfide locks the two domains of the enzyme, preventing catalysis, and we have tentatively identified the two critical cysteine residues in the chloroplast enzyme (D. Li, F.J. Stevens, M. Schiffer and L.E. Anderson (1994) Biophys J. 67: 29–35). We reasoned that if activation of this enzyme involves these cysteines that enzymes lacking one or both should be active in the dark and insensitive to reductants. One of these cysteines is present in the enzymes from Anabaena variabilis and Synechocystis PCC 6803 but the other is not. Consistent with the proposed mechanism, glyceraldehyde-3-P dehydrogenase is not affected by DTT-treatment in extracts of either of these cyanobacteria. Fructosebisphosphatase is DTT-activated in extracts of both of these cyanobacteria and glucose-6-P dehydrogenase is inactivated in Synechocystis, as in higher plant chloroplasts. Apparently reductive modulation is possible in these cyanobacteria but glyceraldehyde-3-P dehydrogenase is not light activated. 相似文献
105.
Evidence for selective effects of vanadium on adipose cell metabolism involving actions on cAMP-dependent protein kinase 总被引:1,自引:0,他引:1
The insulin-like effects of vanadiumin vivo are likely to be achieved at micromolar concentrations. Demonstrated effects of vanadium on adipose tissue of streptozotocin-diabetic rats include inhibition of basal and stimulated rates of lipolysis and effects on fat cell protein phosphorylation. The studies described below examined the effects of vanadium (to a maximum concentration of 0.5 mM) on adipose cells or tissuein vitro. Vanadium, added as a vanadyl-albumin complex or as sodium orthovanadate, produced a marked (greater than 50%) inhibition of isoproterenol-stimulated lipolysis. Inhibition of lipolysis equivalent to that seen with insulin, was achieved with 100 M vanadium. In contrast, no insulin-like stimulation ofde novo fatty acid biosynthesis was observed with vanadium below 0.5 mM. Surprisingly, the antilipolytic effects of vanadium persisted in the presence of cilostamide, an inhibitor of the insulin-sensitive isoform of cyclic nucleotide phosphodiesterase. Studies with purified preparations of the catalytic subunit of cyclic AMP-dependent protein kinase revealed dose-dependent inhibition with vanadyl-glutathione (to a maximum of 40% inhibition). Equivalent inhibition of cyclic AMP-dependent phosphorylation of Kemptide (50%) was observed upon incubation of freshly-prepared fat-pad supernatant fractions with vanadyl-glutathione. These results suggest that effects of low concentrations of vanadium may be mediated, at least in part, by actions on the catalytic subunit of cyclic AMP-dependent protein kinase. 相似文献
106.
中国中生代晚期蛇蛉化石研究(蛇蛉目:巴依萨蛇蛉科,中蛇蛉科,异蛇蛉科) 总被引:10,自引:1,他引:9
本文根据最新采获的保存完好的蛇蛉化石,对中国古生代晚期蛇蛉化石巴依萨蛇蛉科,中蛇蛉科和异蛇蛉科的有关属种的构造特征,分类位置和异我进行新的补充和厘定,建立4个新属:野蛇蛉属Rudiraphidia gen。nov,小蛇蛉属Mioraphidia gen。nov。普蛇蛉属Xynoraphidia gen。nov。丽蛇蛉属Caloraphidia gen,nov;7个新种;美脉巴依萨蛇蛉Baissop 相似文献
107.
Genetic Analysis of Parasitism in the Soybean Cyst Nematode Heterodera Glycines 总被引:2,自引:0,他引:2
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A genetic analysis of parasitic ability in the soybean cyst nematode Heterodera glycines was performed. To identify and characterize genes involved in parasitism, we developed three highly inbred H. glycines lines, OP20, OP25 and OP50, for use as parents for controlled crosses. Through these crosses, we have identified genes in the inbred parents that control reproduction of the nematode on hosts that carry resistance genes. These genes, designated as ror-* for reproduction on a resistant host, segregate in a normal Mendelian fashion as independent loci. Host range tests of F(1) generation progeny indicated that at least one parasitism gene in both the OP20 and OP50 lines for host PI 88788 was dominant. Parasitism genes in OP50 for hosts ``Peking' and PI 90763 are recessive. Two types of single female descent populations, a single backcrossed BC(1)F(2)-derived and a double backcrossed BC(2)F(1)-derived, were established on the susceptible soybean cultivar ``Lee 68.' Host range tests for parasitism in these lines demonstrated the presence of two independent genes in OP50, one for host PI 88788 designated ror-1 and one for host PI 90763 designated ror-2. OP20 carries two independent genes for parasitism on PI 88788, designated as alleles kr3 and kr4. 相似文献
108.
The soybean cyst nematode, Heterodera glycines, is one of the most economically important pathogens of soybean. Effective management of the nematode is often dependent on the planting of resistant soybean cultivars. During the past 40 years, more than 60 soybean genotypes and plant introductions (PI) have been reported as resistant to H. glycines. About 130 modern soybean cultivars registered in the United States are resistant to certain races of H. glycines. Several resistance genes have been identified and genetically mapped; however, resistance levels in many soybean cultivars are not durable. Some older cultivars are no longer resistant to certain H. glycines populations in many production areas, especially if a soybean monoculture has been practiced. Past soybean registration reports show that all resistant cultivars developed in public institutions from the mid-1960s to the present have been derived from five PIs. This narrow genetic background is fragile. To further complicate the issue, soybean-H. glycines genetic interactions are complex and poorly understood. Studies to identify soybean resistance genes sometimes have overlapped, and the same genes may have been reported several times and designated by different names. Nevertheless, many potential resistance genes in existing germplasm resources have not yet been characterized. Clearly, it is necessary to identify new resistance genes, develop more precise selection methods, and integrate these resistance genes into new cultivars. Rational deployment of resistant cultivars is critical to future sustained soybean production. 相似文献
109.
110.
周荣华 《中国科学:生命科学英文版》1997,40(6):657-664
Using genomicin-situ hybridization (GISH) technique, 7 translocation-addition lines, 6 translocation and translocation-addition lines, 2 ditelosomic
addition lines and 1 translocation line were identified fromTriticum aestivum L. -Psathyrostachys juncea (Fisch.) Nevski intergeneric hybrids, of which translocation-addition and translocation and translocation-addition lines
were not found in other reports. No substitutions and disornic additions were detected in the, hybrids and breakages occurred
in allP. juncea chromosomes studied. Results have shown that the improved GISH technique is a rapid and economical method for use in this
field. 相似文献