the dark side of life: skotomorphogenesis. cells and cell growth membranes and cell walls...
Post on 20-Dec-2015
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The dark side of life:
Skotomorphogenesis
Cells and cell growthMembranes and cell walls Fertilization and
embryogenesis
Seed development and dormancy
Germination
Water transport
Water relations
Plant nutrition
Solute transport
Gene function
Skotomorphogenesis
Three learning goals:
- what is a skotomorphogenesisplant development without lightrequirements:
dark regulated developmenttranscription factors that react to darkness
- photoreceptors and their integration in developmenthow plants “see” light and what happens thenrequirements:
photoreceptor molecules that are sensitive at appropriate wavelengths
- integration of skotomorphogenesis and photomorphogenesisrequirements:
signal transduction apparatus that connects light and dark development
What is not regulated by light ???
And how is it regulated???
SKOTOMORPHOGENESIS
Photomorphogenesis Skotomorphogenesis
SKOTOMORPHOGENESIS
Skotomorphogenesis
Light has an influence on seedling development
Skotomorphogenesis Photomorphogenesis Hypocotyl: long short
Apical hook: closed open
Cotyledons: closed expanded
Chloroplasts: proplastids fully developed
Photosynthesis: no yes
Light switch in the dark
Cotyledon expansion
Reduced hypocotylelongation
Open apical hook
closed apical hook Non-expanded
cotyledons
Etiolated hypocotyl
Is skotomorphogenesis achived via active repression of photomorphogenesis
How to perform genetic approaches todecifer light regulation in plants ???
How to perform genetic approaches todecifer light regulation in plants ???
Photomorphogenesisin dark grown seedlings
Skotomorphogenesis in light grown seedlings
Asking simple questions
Getting complicated answers !!
Shorthypocotyl
Expanded cotyledons
Open apical hook
Skotomorphogenesis in the light
Dark
Light
wild-type
cop/detmutants
COP and DET proteins inhibit photomorphogenesis
Regulation of skotomorphogenesis by GA
Germination in dark and light