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101.
102.
D. M. Lonsdale R. L. Allen D. Belostotsky T. K. Ghose A. J. Harvey H. J. Rogers S. J. Tebbut M. Trick 《Plant cell reports》1995,15(1-2):154-158
Summary The promoters of a tobacco actin gene, a tobacco pectate lyase, a tobacco and maize polygalacturonase and aBrassica S-locus related gene have been fused to the-glucuronidase reporter gene and their activities determined by biolistic transient assay in tobacco pollen. In stably transformed tobacco all the transgenes with the exception of Cauliflower Mosaic Virus-35S--glucuronidase appear to express efficiently in maturing pollen. Transient assay analysis showed that the tobacco pectate lyase and the polygalacturonase constructs were 8x more active than the tobacco actin construct, and that the tobacco polygalacturonase construct was some 33x more active than the maize polygalacturonase construct. Constructional manipulations that altered the lengths of the 5-untranslated leaders including one which resulted in the removal of a 490 bp leader intron had little effect on the observed level of expression. However, the alteration of the context of the ATG from A/TnnATGG to CnnATGT resulting in a 70% reduction in the observed levels of activity, was obtained with the pectate lyase and polygalacturonase promoters. An identical reductional was also observed in transgenic plant populations transformed with the polygalacturonase transgenes.Abbreviations GUS
-glucuronidase
- LUC
luciferase
- NosTer
nopaline synthase terminator
- CaMV
Cauliflower Mosaic Virus
- UTL
untranslated leader
- PCR
polymerase chain reaction
- PG
polygalacturonase
- Npg
tobacco polygalacturonase
- Pl
pectate lyase
- Ac
actin 相似文献
103.
Lectin recognition of host-like saccharide motifs in streptococcal cell wall polysaccharides 总被引:10,自引:0,他引:10
Cisar John O.; Sandberg Ann L.; Abeygunawardana Chitrananda; Reddy G.Prabhakar; Bush C.Allen 《Glycobiology》1995,5(7):655-662
Viridans streptococci that participate in the microbial colonizationof teeth have cell wall polysaccharides composed of linear phosphodiester-linkedhexa- or heptasaccharide repeating units, each containing ahost-like disaccharide motif, either Galß1 相似文献
104.
Allen D. Ziebur 《Theoretical population biology》1984,26(3):315-319
P. H. Leslie (1945, Biometrika, 33, 183–212) (and others) introduced vector-matrix growth difference equations to model populations in which birth and death rates are age-dependent. We develop differential versions of these equations in both the unrestricted growth and logistic cases. We find that the vector logistic equations (difference and differential) are explicitly solvable in terms of solutions of the unrestricted equations, even when vital rates vary with time. These explicit solution formulas make it easy to determine the behavior of solutions as time goes on. 相似文献
105.
Allen M. Young 《Acta biotheoretica》1984,33(3):163-198
An hypothesis tout court is proposed to account for the association of cicadas (Homoptera: Cicadidae) with large-sized trees of the family Leguminosae in both climax forest formations and forest remnants in Central America. Based upon extensive field studies of these insects in Costa Rica, final-instar nymphal skins of many genera and species of Neotropical cicadas appear to be aggregated annually around individual large legume trees in a broad range of habitats in Costa Rica, and much of the reproductive behavior of the adult insects is also centered around these trees. A series of testable subhypotheses are generated based largely upon the assumption that cicadas, primarily through egg-placement behavior and nymphal feeding behavior, have coevolved with legume trees in climax forest formations of Central America, and perhaps elsewhere in the Neotropical Region. The root crowns of such trees, with some exceptions, might be optimal feeding sites for cicada nymphs in tropical forests. 相似文献
106.
Douglas L. Vizard R.Allen White Allen T. Ansevin 《Archives of biochemistry and biophysics》1984,229(2):498-508
High-resolution thermal denaturation was used to measure the heterogeneity within repeated DNA sequences. An analysis of combined denaturation/redenaturation experiments on mouse satellite DNA suggests the existence of two minor components, one of which does not appear in the prepared EcoRII monomer. The resolving power of the denaturation/redenaturation experiment is estimated and contrasted with that of the reassociation experiment, often used to estimate repeated sequence heterogeneity. A mathematical model of the redenaturation experiment was developed and applied to mouse satellite data; the results suggest that only one-fourth of the mismatched base pairs are energetically significant in the reduction of heteroduplex stability. 相似文献
107.
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110.
Meiheng Yang Howard Allen Hisao Fukushima Richard A. DiCioccio 《Glycoconjugate journal》1984,1(1):15-19
Fucosidosis is an autosomal recessive lysosomal storage disease resulting from the absence of -l-fucosidase activity. Two natural missense mutations (G197A) and (A860G) within the -l-fucosidase gene have been reported to be homozygous in four patients with fucosidosis. Expression of wild-type and mutated -l-fucosidase cDNAs in COS-1 cells revealed complete deficiency of -l-fucosidase for the G197A transition and a normal level of enzyme for A860G. We therefore conclude that the change of G197A is responsible for fucosidosis in the patients while A860G is a normal polymorphic variant of -l-fucosidase. 相似文献