FOTOMORFOGÉNESIS

• Desarrollo foto y escotomorfogénico• Fotorreceptores

– Fitocromos– Criptocromos– FototropinasTransducción de señales por los fitocromosRitmo circadianoCOP9-signalosoma

Plant development normally shows plasticity within certain bounds, that is, without falling into extreme phenotypes. Theoccurrence of multiple receptors and downstream signalling pathways, negative regulators, and positive and negative interactionsprovides the homeostasis that prevents exaggerated phenotypes under extreme environments. This system leaves room for changebecause the actual phenotype obtained within the range of normal developmental plasticity can depend on just a few receptors, negativeregulators that establish the need for further environmental cues, and interactions that modulate the relationship between signal input andoutput.

Convergencia de la información de los fotones

De-etiolación de una plántula

Plantulas creciendo en distintas condiciones de luz y análisis de la expresión génica correspondiente mediante microarrays.

CONCEPTO DE FOTOMORFOGENESIS Y ESCOTOMORFOGENESIS

fotorreceptores de plantasfotorreceptores de plantas

Dominios en el fitocromo

Luz blanca Luz Roja

Luz AzulLuz Infrarroja

Mutantes de fitocromo en Arabidopsis

the network that connects developmental genes to environmentalcues.

Phytochrome photoperception and signal transduction in seedling photomorphogenesis.

Light-induced nuclear translocation of phyA.

PIF3

PKS1

PKS1 expression

PKS1 interacts with phytochrome

Seedlings overexpressing PKS1 have reduced sensitivity to white light.

Light-regulated PKS1 phosphorylation by phyA in vitro.

Direct targeting of light signals to primary photoresponse genes.

Photons convey information.

Cryptochrome and flowering time

Phot1

Phot1-2

EL CONTROL DEL DESARROLLO FOTOMORFOGÉNICO

-Sistema de control por degradación

--EL COP9 signalosoma

-COP1

-Componentes del sistema de identificación y

degradación

-Papel del criptocromo cry1

-Control del hy5

La red que conecta los genes del desarrollo con las fluctuaciones ambientales

Hy5

The light regulation of HY5 is dependent on the nuclear abundance of COP1 and its ability to interact with COP1.