Etiolation
Mostrando 25-36 de 43 artigos, teses e dissertações.
-
25. Modifications of Etioplasts in Cotyledons during Prolonged Dark Growth of Sugar Beet Seedlings (Identification of Etiolation-Related Plastidial Aminopeptidase Activities).
We studied the effects of prolonged dark growth on proplastids and etioplasts in cotyledons of sugar beet (Beta vulgaris L.) seedlings. Differentiation of proplastids into etioplasts occurred between d 4 and d 6 after imbibition, with the typical characteristics of increased synthesis of plastidial proteins, protein and carotenoid accumulation, size increase
-
26. Light-dependent chloroplast development and expression of a light-harvesting chlorophyll a/b-binding protein gene in the gymnosperm Ginkgo biloba.
Unlike conifers, the gymnosperm Ginkgo biloba is dependent on light for chlorophyll (Chl) synthesis and initiation of chloroplast development. Dark-grown seedlings show complete etiolation, including no detectable Chl accumulation, no leaf expansion, and increased hypocotyl elongation. When dark-grown seedlings are placed in white light, Chl synthesis and le
-
27. Genetic Interactions between Phytochrome A, Phytochrome B, and Cryptochrome 1 during Arabidopsis Development1
Single, double, and triple null combinations of Arabidopsis mutants lacking the photoreceptors phytochrome (phy) A (phyA-201), phyB (phyB-5), and cryptochrome (cry) 1 (hy4-2.23n) were examined for de-etiolation responses in high-fluence red, far-red, blue, and broad-spectrum white light. Cotyledon unhooking, unfolding, and expansion, hypocotyl growth,
American Society of Plant Physiologists.
-
28. A Proteomic Analysis of Maize Chloroplast Biogenesis1
Proteomics studies to explore global patterns of protein expression in plant and green algal systems have proliferated within the past few years. Although most of these studies have involved mapping of the proteomes of various organs, tissues, cells, or organelles, comparative proteomics experiments have also led to the identification of proteins that change
The American Society for Plant Biologists.
-
29. Changing Ratios of Phototransformable Protochlorophyll and Protochlorophyllide of Bean Seedlings Developing in the Dark 1
Protochlorophyll (Pchl) and protochlorophyllide (Pchlide) are at comparable levels in 2-day-old (young) etiolated bean leaves (Phaseolus vulgaris L. var. Red Kidney). During subsequent development in the dark, both pigments increase, but the rate of Pchlide increase is greater than that of Pchl, leading to the commonly observed predominance of Pchlide beyond
-
30. The Effects of Cytokinin and Light on Hypocotyl Elongation in Arabidopsis Seedlings Are Independent and Additive.
Cytokinin has been reported to mimic some of the effects of light on de-etiolation responses in dark-grown Arabidopsis seedlings. The interaction between cytokinin and light was examined by analyzing cytokinin dose and light fluence effects on hypocotyl elongation in wild-type and mutant Arabidopsis seedlings with defects in light or hormone responses. It wa
-
31. Gibberellins Repress Photomorphogenesis in Darkness1
Plants undergo two different developmental programs depending on whether they are growing in darkness (skotomorphogenesis) or in the presence of light (photomorphogenesis). It has been proposed that the latter is the default pathway followed by many plants after germination and before the seedling emerges from soil. The transition between the two pathways is
The American Society for Plant Biologists.
-
32. A Putative Role for the Tomato Genes DUMPY and CURL-3 in Brassinosteroid Biosynthesis and Response1
The dumpy (dpy) mutant of tomato (Lycopersicon esculentum Mill.) exhibits short stature, reduced axillary branching, and altered leaf morphology. Application of brassinolide and castasterone rescued the dpy phenotype, as did C-23-hydroxylated, 6-deoxo intermediates of brassinolide biosynthesis. The brassinolide precursors campesterol, campestanol, and 6-deox
American Society of Plant Physiologists.
-
33. Light Regulates COP1-Mediated Degradation of HFR1, a Transcription Factor Essential for Light Signaling in Arabidopsis
Arabidopsis thaliana seedlings undergo photomorphogenesis in the light and etiolation in the dark. Long Hypocotyl in Far-Red 1 (HFR1), a basic helix-loop-helix transcription factor, is required for both phytochrome A–mediated far-red and cryptochrome 1–mediated blue light signaling. Here, we report that HFR1 is a short-lived protein in darkness and is de
American Society of Plant Biologists.
-
34. Mitochondrial and peroxisomal beta-oxidation capacities of organs from a non-oilseed plant.
Until recently, beta-oxidation was believed to be exclusively located in the peroxisomes of all higher plants. Whilst this is true for germinating oilseeds undergoing gluconeogenesis, evidence demonstrating mitochondrial beta-oxidation in other plant systems has refuted this central dogma of plant lipid metabolism. This report describes a comparative study o
-
35. The Heme-Oxygenase Family Required for Phytochrome Chromophore Biosynthesis Is Necessary for Proper Photomorphogenesis in Higher Plants1
The committed step in the biosynthesis of the phytochrome chromophore phytochromobilin involves the oxidative cleavage of heme by a heme oxygenase (HO) to form biliverdin IXα. Through positional cloning of the photomorphogenic mutant hy1, the Arabidopsis HO (designated AtHO1) responsible for much of phytochromobilin synthesis recently was identified. Using
American Society of Plant Physiologists.
-
36. Expression of Xanthophyll Biosynthetic Genes during Light-Dependent Chloroplast Differentiation1
In higher plants, etioplast to chloroplast differentiation is characterized by dramatic ultrastructural changes of the plastid and a concomitant increase in chlorophylls and carotenoids. Whereas the formation and function of carotenes and their oxygenated derivatives, the xanthophylls, have been well studied, little is known about the regulation of the g
The American Society for Plant Biologists.