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31.
The chalcone synthase multigene family of Petunia hybrida (V30): differential,light-regulated expression during flower development and UV light induction 总被引:11,自引:0,他引:11
We have analysed the expression of the 8–10 members of the gene family encoding the flavonoid biosynthetic enzyme chalcone synthase (CHS) from Petunia hybrida. During normal plant development only two members of the gene family (CHS-A and CHS-J) are expressed. Their expression is restricted to floral tissues mainly. About 90% of the total CHS mRNA pool is transcribed from CHS-A, wheares CHS-J delivers about 10% in flower corolla, tube and anthers. Expression of CHS-A and CHS-J during flower development is coordinated and (red) light-dependent. In young seedlings and cell suspension cultures expression of CHS-A and CHS-J can be induced with UV light. In addition to CHS-A and CHS-J, expression of another two CHS genes (CHS-B and CHS-G) is induced in young seedlings by UV light, albeit at a low level. In contrast to CHS genes from Leguminoseae, Petunia CHS genes are not inducible by phytopathogen-derived elicitors. Expression of CHS-A and CHS-J is reduced to a similar extent in a regulatory CHS mutant, Petunia hybrida Red Star, suggesting that both genes are regulated by the same trans-acting factors. Comparison of the promoter sequences of CHS-A and CHS-J reveals some striking homologies, which might represent cis-acting regulatory sequences. 相似文献
32.
U. D. Bongale 《Hydrobiologia》1989,171(2):103-106
Six new taxa including two new species (Cosmarium bourrellyi Bongale sp. nov. andC. desikacharyi Bongale sp. nov.) and four new varieties (C. auriculatum var.protrusum Bongale var. nov.,C. pachydermum var.inflatum Bongale var. nov.,C. pseudoconnatum var.tuberculans Bongale var. nov. andC. quadrum var.rotundatum Bongale var. nov.) are reported. Algae were collected from a paddy field at Belgaum. 相似文献
33.
Thomas E. Fricke Arland Thornton Dilli R. Dahal 《Human ecology: an interdisciplinary journal》1990,18(3):283-313
This paper explores familial contexts of transition to a wage labor economy using ethnographic and survey data from Tamang communities at the northern edge of Nepal's Kathmandu Valley. Historically agro-pastoralist, the Tamang of this area have experienced social watersheds drawing them into ever closer relationships with Kathmandu. The earliest was their nineteenth century induction into corvée labor for national elites; more recent has been the accelerating monetization of the twentieth century. This analysis demonstrates trends and frames hypotheses about the social structuring of this latest process, testing them at the individual level with combined ethnographic and survey data from 1028 respondents. Multivariate analyses explore the effects of birth cohort, education, domestic group status, and settlement location on participation in non-family organized wage work. Substantive findings are related to the broader historical literature on household and family with special attention to varieties of subsistence to monetized transition. 相似文献
34.
Eckhard Fischer Birgit Strehlow Dieter Hartz Volkmar Braun 《Archives of microbiology》1990,153(4):329-336
After uptake of microbial ferrisiderophores, iron is assumed to be released by reduction. Two ferrisiderophore-reductase activities were identified in Escherichia coli K-12. They differed in cellular location, susceptibility to amytal, and competition between oxygen and ferrichrome-iron(III) reduction. The ferrisiderophore reductase associated with the 40,000×g sediment (membrane-bound enzyme) was inhibited by 10 mM amytal in contrast to the ferrisiderophore reductase present in the 100,000×g supernatant (soluble enzyme). Reduction by the membrane-bound enzyme followed sigmoid kinetics, but was biphasic in the case of the soluble enzyme. The soluble reductase could be assigned to a protein consisting of a single polypeptide of M
r
26000. Reduction of iron(III) by the purified enzyme depended on the addition of NADH or NADPH which were equally active reductants. The cofactor FMN and to a lesser degree FAD stimulated the reaction. Substrate specificity of the soluble reductase was low. In addition to the hydroxamate siderophores arthrobactin, schizokinen, fusigen, aerobactin, ferrichrome, ferrioxamine B, coprogen, and ferrichrome A, the iron(III) complexes of synthetic catecholates, dihydroxy benzoic acid, and dicitrate, as well as carrier-free iron(III) were accepted as substrates. Both ferrisiderophore reductases were not controlled by the fur regulatory system and were not suppressed by anaerobic growth.Abbreviations DHB
dihydroxybenzoic acid
- MECAM
1,3,5-N,N,N-tris-(2,3-dihydroxybenzoyl)-triamino-methylbenzene
- MECAMS
2,3-dihydroxy-5-sulfonyl-derivative of MECAM 相似文献
35.
湖北省淡水蟹类的动物地理学分析及新亚种的记述(软甲纲:十足目) 总被引:2,自引:0,他引:2
湖北省蟹类地理分布的分析结果,古北界和东洋界的划线以31°N上下为过渡区,中部以汉水为界,113°E以东则逐步转向黄淮平原区,因此该省不仅是南北的转折,也是东西的交接地带。文中报道了两个新亚种:Sinopotamon denticulatum styxum S.depressum obliquum。 相似文献
36.
本文报道了岩羊小肠的祁连毛圆线虫,新种Trichostrongylus qilianensis sp. nov., 其形态与已发表的39种毛圆线虫均有明显区别。 相似文献
37.
龟鳖类锥虫两新种(动体目:锥体科) 总被引:1,自引:0,他引:1
龟鳖类锥虫的研究,国内外均比较少。本文记述了在中华鳖和乌龟血液中发现的两新种,鳖锥虫和龟锥虫。这是国内首次对龟鳖类锥虫研究的报道。 相似文献
38.
本文记述中国新纪录正鳃金龟属Malaisius Arrow(1941)及4个新种——云南松正鳃金龟Malaisius pinae,介正鳃金龟M.intermedius,背黑正鳃金龟M.melanodiscus及闽正鳃金龟M.fujianensls。结合4新种之特征,重新描述了本属属征,指出正鳃金龟属与歪鳃金龟属Cyphochilus Waterheuse近缘。 相似文献
39.
本文记述斯氏蚤属Smitipsylla Lewis,1971一新种,方突斯氏蚤S. quadrata sp. nov.。本新种的发现,是斯氏蚤属在中国的首次纪录。本文对其属征作了概述。 相似文献
40.
本文记述了中国半翅目仰蝽科一新种:突顶小仰蝽Anisops protracta sp. nov. 及一新记录:南小仰蝽A. exigera Horvath。对于新种进行了描述,并附特征插图8幅。 相似文献