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131.
Plant Molecular Biology - The α-Amy1 and α-Amy2 genes of wheat produce distinct subsets of α-amylase isozymes which show different patterns of expression in wheat aleurone cells and... 相似文献
132.
John T. Christeller Betty E. Terzaghi Diana F. Hill W. A. Laing 《Plant molecular biology》1985,5(4):257-263
Summary The ribulose bisphosphate carboxylase/oxygenase (EC4.1.1.39) (RubisCO) large and small subunit genes from Anacystis nidulans have been cloned as a single fragment into M 13mp10 and pEMBL8 and expressed in Escherichia coli. From M 13mp10 a low yield of enzyme with high specific activity was obtained. The molecular weight of the active enzyme was 260 000 Da and of the inactive enzyme approximately 730 000 Da. The small and large subunits cloned separately did not express activity. The RubisCO gene cloned into pEMBL8 expressed activity up to 22 times that from the M 13 cloned RubisCO DNA. The RubisCO protein produced by the pEMBL cloned gene had a normal MW (550 000). Immunoprecipitation and polyacrylamide gel electrophoresis showed the presence of both large and small subunits. 相似文献
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136.
Climate and plant distribution at global and local scales 总被引:12,自引:0,他引:12
This paper investigates, with predictive models, the utility of ecophysiological responses to climate as predictors of plant distribution. At the global scale responses to extreme minimum temperatures and to the hydrological budget effectively predict the distribution limits of the major vegetation types of the World. A minimum temperature of -15°C, for example, appears critical in controlling the poleward spread of vegetation that is dominated by evergreen broadleaved species; however, the presence or absence of more frost resistant species, such as those that are deciduous broadleaved, is not obviously explained in terms of extremes of climate. In such cases, predicting the competitive relationships between species is necessary and dependent on the climatic sensitivity of population dynamics.We are grateful to Hans de Kroon for discussions on the application of matrices to ecology. 相似文献
137.
Yvonne H. Edwards Sue Povey Kay M. Levan Catherine E. Driscoll Jose Luis Millan Erwin Goldberg 《Genesis (New York, N.Y. : 2000)》1987,8(4):219-232
From the data presented in this report, the human LDHC gene locus is assigned to chromosome 11. Three genes determine lactate dehydrogenase (LDH) in man. LDHA and LDHB are expressed in most somatic tissues, while expression of LDHC is confined to the germinal epithelium of the testes. A human LDHC cDNA clone was used as a probe to analyze genomic DNA from rodent/human somatic cell hybrids. The pattern of bands with LDHC hybridization is easily distinguished from the pattern detected by LDHA hybridization, and the LDHC probe is specific for testis mRNA. The structural gene LDHA has been previously assigned to human chromosome 11, while LDHB maps to chromosome 12. Studies of pigeon LDH have shown tight linkage between LDHB and LDHC leading to the expectation that these genes would be syntenic in man. However, the data presented in this paper show conclusively that LDHC is syntenic with LDHA on human chromosome 11. The terminology for LDH genes LDHA, LDHB, and LDHC is equivalent to Ldhl, Ldh2, and Ldh3, respectively. 相似文献
138.
J. P. Bourgin C. Missonier J. Goujaud 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(1):11-14
Summary Direct selection of cybrids by simultaneous selection for donor chloroplasts and for the recipient nuclei is described. Mesophyll protoplasts of two tobacco (Nicotiana tabacum) mutants, SR1 (streptomycin resistant) and Valr-2 (valine resistant), were fused by polyethylene glycol treatment. Streptomycin resistance in the SR1 mutant is a maternally inherited chloroplast trait while valine resistance is a Mendelian (nuclear) digenic recessive character. The fused protoplast population was cultured and colonies were selected for resistance to valine (1 mM) and streptomycin (343 M). The efficiency of selection has been confirmed in three clones by demonstrating seed transmission of both streptomycin and valine resistances. In one subclone both streptomycin resistant and sensitive plants were obtained indicating that the streptomycin sensitive chloroplasts had not been totally eliminated by growth on the selective medium. 相似文献
139.
T. A. Kavanagh J. N. Timmis 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(3):337-345
Summary Restriction and hybridization analysis of cucumber native ribosomal (r) DNA purified from actinomycin-D/CsCl gradients suggested that the repeat units were heterogeneous in both length and sequence. Several full length rDNA repeat units were cloned and five are described which account for all the EcoR I and Xba I fragments present in native DNA. One of a number of BamH I sites found in the clones is not found in a proportion of native rDNA because of base modification. Restriction maps are described for the representative clones and aligned with R-loop maps obtained from electron microscope analysis of each type of repeat unit hybridized under R-loop conditions to pure 18S and 25S rRNAs. The major heterogeneity is explained by differences in length of the external spacer region and by a proportion of the repeat units showing a restriction fragment length polymorphism on EcoR I digestion. The regions coding for 18S and 25S rRNA are uninterrupted and highly conserved. 相似文献
140.
D. Vakeria G. A. Codd A. M. Hawthornthwaite W. D. P. Stewart 《Archives of microbiology》1986,145(3):228-233
A gene bank of the nutritionally versatile, nitrogen-fixing cyanobacterium Chlorogloeopsis fritschii was constructed in Charon 4A. 2,800 recombinants containing 10–20 kbp C. fritschii DNA fragments were screened by Southern hybridization using probes containing the genes for the large (LSU) and small (SSU) subunits of ribulose bisphosphate carboxylase/oxygenase (RuBisCO) from Anacystis nidulans. A single recombinant plaque (CDG1) containing a 10.9 kbp EcoR1 fragment from C. fritschii hybridized to both the LSU and SSU probes, indicating a possible linkage of these RuBisCO genes in C. fritschii. RuBisCO activity and protein were detected in CDG1 lysates of Escherichia coli. Hybridization was also obtained between C. fritschii DNA and the LSU probe from Chlamydomonas reinhardtii, although no homology was detected using the LSU probe from maize or the SSU probe from pea.Abbreviations RuBisCO
d-ribulose 1,5-bisphosphate carboxylase/oxygenase
- RuBP
d-ribulose 1,5-bisphosphate
- LSU
large subunit of RuBisCO
- SSU
small subunit of RuBisCO
- SDS
sodium dodecyl sulphate
- DOC
deoxycholate 相似文献