Biliverdin reductase-induced phytochrome chromophore deficiency in transgenic tobacco.
Plant Physiol
; 125(1): 266-77, 2001 Jan.
Article
en En
| MEDLINE
| ID: mdl-11154335
ABSTRACT
Targeted expression of mammalian biliverdin IXalpha reductase (BVR), an enzyme that metabolically inactivates linear tetrapyrrole precursors of the phytochrome chromophore, was used to examine the physiological functions of phytochromes in the qualitative short-day tobacco (Nicotiana tabacum cv Maryland Mammoth) plant. Comparative phenotypic and photobiological analyses of plastid- and cytosol-targeted BVR lines showed that multiple phytochrome-regulated processes, such as hypocotyl and internode elongation, anthocyanin synthesis, and photoperiodic regulation of flowering, were altered in all lines examined. The phytochrome-mediated processes of carotenoid and chlorophyll accumulation were strongly impaired in plastid-targeted lines, but were relatively unaffected in cytosol-targeted lines. Under certain growth conditions, plastid-targeted BVR expression was found to nearly abolish the qualitative inhibition of flowering by long-day photoperiods. The distinct phenotypes of the plastid-targeted BVR lines implicate a regulatory role for bilins in plastid development or, alternatively, reflect the consequence of altered tetrapyrrole metabolism in plastids due to bilin depletion.
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Fitocromo
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Nicotiana
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Clorofila
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Plantas Modificadas Genéticamente
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Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH
Tipo de estudio:
Qualitative_research
Idioma:
En
Revista:
Plant Physiol
Año:
2001
Tipo del documento:
Article
País de afiliación:
Estados Unidos