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41.
ROGER T. KOIDE 《The New phytologist》1991,117(3):365-386
42.
Universal primers for amplification of three non-coding regions of chloroplast DNA 总被引:90,自引:0,他引:90
Six primers for the amplification of three non-coding regions of chloroplast DNA via the polymerase chain reaction (PCR) have been designed. In order to find out whether these primers were universal, we used them in an attempt to amplify DNA from various plant species. The primers worked for most species tested including algae, bryophytes, pteridophytes, gymnosperms and angiosperms. The fact that they amplify chloroplast DNA non-coding regions over a wide taxonomic range means that these primers may be used to study the population biology (in supplying markers) and evolution (inter- and probably intraspecific phylogenies) of plants. 相似文献
43.
Jac M. M. J. G. Aarts Jan G. J. Hontelez Peter Fischer Ruud Verkerk Albert van Kammen Pim Zabel 《Plant molecular biology》1991,16(4):647-661
With a view to cloning the root-knot nematode resistance gene Mi in tomato by chromosome walking, we have developed a molecular probe for the tightly linked acid phosphatase-1 (Aps-1) locus. The acid phosphatase-1 allozyme (APS-11), encoded by the Aps-1
1 allele originating from Lycopersicon peruvianum, was purified to apparent homogeneity from tomato roots and suspension cells. Microsequencing of CNBr and tryptic peptides generated from APS-11 provided a partial amino acid sequence, which accounted for approximately 23% of the protein and revealed two stretches of homology with soybean proteins KSH3 and VSP27, comprising 22 matches within 26 amino acid residues. The partial amino acid sequence information enabled us to isolate a 2.4 kb genomic Aps-1
1 sequence by means of the polymerase chain reaction (PCR), primed by degenerate pools of oligodeoxyribonucleotides, synthesized on the basis of the amino acid sequences. Synthesis of the 2.4 kb PCR product was specific for genomic templates carrying the L. peruvianum Aps-1
1 allele. Crucial to the priming specificity and the synthesis of the 2.4 kb genomic sequence was the use of degenerate primer pools in which the number of different primer species was limited by incorporating deoxyinosine phosphate residues at three and four base ambiguities. In using cDNA as a template, a 490 bp sequence was obtained, indicating a high proportion of intron sequences in the 2.4 kb genomic Aps-1
1 sequence. The Aps-1
1 origin of the PCR product was confirmed by RFLP (restriction fragment length polymorphism) analysis, using both a chromosome 6 substitution line and a pair of nearly isogenic lines, differing for a small chromosomal region around the Aps-1/Mi loci. 相似文献
44.
Ignacio R. Rodriguez Pedro Gonzales J. Samuel Zigler Teresa Borrás 《生物化学与生物物理学报:疾病的分子基础》1992,1180(1):44-52
A congenital cataract present in guinea pigs provided a unique opportunity to study a hereditary lens diseases at the molecular level. ζ-crystallin, one of the most abundant guinea pig lens proteins, was found to be altered in the lens of cataractous animals. Several ζ-crystallin cDNA clones were isolated from a cataractous lens library and found to contain a 102-bp deletion towards the 3′ end of the coding region. The deletion does not interfere with the reading frame but results in a protein 34 amino acids shorter. Sequence analysis of a normal genomic ζ-crystallin clone revealed that the missing 102-bp fragment corresponds to an entire exon (exon 7). PCR analysis of the genomic DNA isolated from cataractous animals showed that exon 7, though missing from the mRNA, is intact in the cataractous genome. Further sequence analysis of the α-crystallin gene disclosed a dinucleotide delection of the universal AG at the acceptor splice-site of intron 6 of the mutant gene. The presence of this mutation results in the skipping of exon 7 during the mRNA processing which in turn results in the altered ζ-crystallin protein. This if the first time a genomic mutation in an enzyme/crytallin gene has been directly linked to a congenital cataract. 相似文献
45.
Shingo Kurabuchi 《Development genes and evolution》1992,201(6):376-382
Summary The relationship between the size and shape of regenerative outgrowth and the quantity of innervation was studied in adult Xenopus laevis. The forelimbs, of which the nerve supply was artificially altered, were amputated midway through the stylopodium and were kept for 1 year. The regenerative outgrowths that formed in normal limbs with an intact nerve supply were mainly spike-shaped and occasionally rod-shaped. However, when the nerve supply to the distal part of the forelimb was augmented by surgically diverting ipsilateral sciatic nerve bundles, the quantity of innervation was increased to about two and a half times that of the normal limb. These hyperinnervated outgrowths were somewhat larger than those of the normally innervated outgrowths and the majority of them were oar-shaped, a type hardly ever encountered in normal regeneration. In contrast, when partial denervation was performed concomitantly with limb amputation, by ablation of the N. radialis at the shoulder joint, the quantity of innervation decreased to about one half that of the normal limb. The outgrowths obtained were spike-shaped in all cases, with their size being about half that of the normally innervated outgrowths. Furthermore, when both the N. radialis and N. ulnaris were ablated in the same way, the amputated limbs were mostly non-regenerative, but some of them regenerated small conical outgrowths. Based on these results, a discussion is presented concerning the relationship between a regenerative outgrowth and the innervation of the forelimb in Xenopus. 相似文献
46.
47.
The effect of ciprofibrate, a hypolipidemic drug, was examined in the metabolism of palmitic (C16:0) and lignoceric (C24:0) acids in rat liver. Ciprofibrate is a peroxisomal proliferating drug which increases the number of peroxisomes. The palmitoyl-CoA ligase activity in peroxisomes, mitochondria and microsomes from ciprofibrate treated liver was 3.2, 1.9 and 1.5-fold higher respectively and the activity for oxidation of palmitic acid in peroxisomes and mitochondria was 8.5 and 2.3-fold higher respectively. Similarly, ciprofibrate had a higher effect on the metabolism of lignoceric acid. Treatment with ciprofibrate increased lignoceroyl-CoA ligase activity in peroxisomes, mitochondria and microsomes by 5.3, 3.3 and 2.3-fold respectively and that of oxidation of lignoceric acid was increased in peroxisomes and mitochondria by 13.4 and 2.3-fold respectively. The peroxisomal rates of oxidation of palmitic acid (8.5-fold) and lignoceric acid (13.4-fold) were increased to a different degree by ciprofibrate treatment. This differential effect of ciprofibrate suggests that different enzymes may be responsible for the oxidation of fatty acids of different chain length, at least at one or more step(s) of the peroxisomal fatty acid -oxidation pathway. 相似文献
48.
Ellsworth C. Alvord Jr. Sarka Hruby Russell E. Martenson Gladys E. Deibler Mona J. Law 《Journal of neurochemistry》1986,47(3):764-771
The specificities of two monoclonal IgM antibodies (18.25 and 21.14.2) evoked in mice with guinea pig myelin basic protein were examined and interpreted in terms of a specific folding of the protein's polypeptide chain. Studies with guinea pig and rabbit myelin basic protein fragments showed that a region encompassing the central Phe-Phe (87-88) sequence is obligatory, but not sufficient, for reactivity with antibody 18.25. Appreciable reactivity was observed for rabbit peptides 22-95 and 45-151, and lower, but significant, reactivity was shown by peptide 32-95. Only very weak reactivity was seen with peptide 44-95. No reactivity was observed with peptide 1-95 after its lysine residues were acetylated, acetamidinated, or guanidinated. These results have been interpreted in terms of a polypeptide chain folding that creates an epitope within sequence Val-Val-His-Phe-Phe-Lys-Asn-Ile-Val (84-92). The specific conformation of this epitope, which includes probably the Lys-89 and possibly the Asn-90 and Val-92 side chains, could be formed by the association of sequence 84-92 with either sequence Ile-Leu-Asp-Ser-Ile-Gly-Arg-Phe-Phe (37-45) or with sequence Val-Leu-Ser-Arg-Phe (108-112) to form beta-sheet structures essentially identical with those that appear to be present in the intact BP [Martenson R.E.J. Neurochem. 46, 1612-1622 (1986)]. The second monoclonal antibody, no. 21.14.2, reacts only with guinea pig myelin basic protein and fragments containing the species-restricted sequence Arg-Ala-Asp-Tyr-Lys-Ser-Lys (129-135).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
49.
Internal transport of O2 from the aerial tissues along the adventitious roots of intact maize plants was estimated by measuring the concentrations of adenine nucleotides in various zones along the root under an oxygen-free atmosphere. Young maize plants were grown in nutrient solution under conditions that either stimulated or prevented the formation of a lysigenous aerenchyma, and the roots (up to 210 mm long) were then exposed to an anaerobic (oxygen-free) nutrient solution. Aerenchymatous roots showed higher values than non-aerenchymatous ones for ATP content, adenylate energy charge and ATP/ADP ratios. We conclude that the lysigenous cortical gas spaces help maintain a high respiration rate in the tissues along the root, and in the apical zone, by improving internal transport of oxygen over distances of at least 210 mm. This contrasted sharply with the low energy status (poor O2 transport) in non-aerenchymatous roots.Abbreviation AEC
adenylate energy charge 相似文献
50.
B. N. Ivanov V. L. Shmeleva V. I. Ovchinnikova 《Journal of bioenergetics and biomembranes》1985,17(4):239-249
The number of protons released inside the chloroplast thylakoids per electron which is transferred through the electron transport chain (H+/e– ratio) was measured in isolated pea chloroplasts at pH 6.0 under continuous illumination and with methyl viologen as an electron acceptor. At saturating light intensity (200 W · m–2) (strong light) the H+/e– ratio was 3. At low intensity (0.9 W · m–2) (weak light) the H+/e– ratio was 2 with dark-adapted chloroplasts, but it was close to 3 with chloroplasts that were preilluminated with strong light. It is shown that the presence of azide in the reaction mixture leads to errors in the determination of the H+/e– ratio due to underestimation of the initial rate of H+ efflux on switching off the light. To explain the above data, we assume that transformation of the electron transport chain occurs during illumination with strong light, namely, the Q cycle becomes operative. 相似文献