1 / 30

BLUE LIGHT RESPONSES

BLUE LIGHT RESPONSES. Photoropism Inhibition of stem stem and hypocotyl elongation Stimulation of chlorophyll and carotenoid synthesis Stomatal opening Chloroplast movements Anthocyanin synthesis. ACTION SPECTRUM. Blue light inhibition of elongation.

abigail-boyd
Download Presentation

BLUE LIGHT RESPONSES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BLUE LIGHT RESPONSES Photoropism Inhibition of stem stem and hypocotyl elongation Stimulation of chlorophyll and carotenoid synthesis Stomatal opening Chloroplast movements Anthocyanin synthesis

  2. ACTION SPECTRUM

  3. Blue light inhibition of elongation

  4. Blue light stimulation of glutamate semialdehyde aminotransferase, an enzyme involved in chlorophyll synthesis

  5. CHLOROPLAST MOVEMENTS -LEMNA DARK WEAK BLUE LIGHT STRONG BLUE LIGHT

  6. DARK

  7. BLUE LIGHT

  8. CLOSE CORRELATION BETWEEN LIGHT AND STOMATAL OPENING

  9. BLUE LIGHT PHOTORECEPTORS • PHOTOTROPINS : phot1 and phot2 • SERVE AS THE BLUE LIGHT PHOTORECEPTORS FOR PHOTOTROPISM, CHLOROPLAST MOVEMEMNTS, AND STOMATAL OPENING • MUTANTS LACK BLUE LIGHT DEPENDENT PHOTOTROPISM, CHLOROPLAST MOVEMENTS, AND STOMATAL OPENING • PHOTOTROPINS ARE FLAVOPROTEINS WITH SER/THR PROTEIN KINASES THAT AUTOPHOSPHORYLATE IN RESPONSE TO BLUE LIGHT

  10. BLUE LIGHT PHOTORECEPTORS (CONT.) 2. CRYPTOCHROMES (cry1 and cry2) • CRYPTOCHROMES PLAY ROLES IN BLUE-LIGHT-MEDIATED GROWTH INHIBITION. MUTANT HYPOCOTYLS ARE NOT INHIBITED BY BLUE LIGHT. • HOWEVER, NO PHOTOCHEMISTRY HAS YET BEEN DEMONSTRATED, AND SO THEY MAY NOT ACT AS PHOTORECEPTORS • CRYPTOCHROMES ALSO FOUND IN ANIMAL CELLS WHERE THEY FUNCTION IN CIRCADIAN RHYTHMS, BUT DO NOT ACT AS PHOTORECEPTORS • CRYPTOCHROMES MAY BE INVOLVED IN SIGNAL TRANSDUCTION DOWNSTREAM OF OTHER BLUE LIGHT PHOTORECEPTORS.

  11. BLUE LIGHT PHOTORECEPTORS (CONT.) ZEAXANTHIN - CAROTENOID LOCATED IN THE CHLOROPLAST - MAY REGULATE STOMATAL OPENING. MUTANTS HAVE REDUCED RESPONSE TO BLUE LIGHT. - ZEAXANTHINS AND PHOTOROPINS MAY WORK TOGETHER IN GUARD CELLS

  12. ZEAXANTHIN CAN UNDERO A CIS-TRANS ISOMERIZATION BLUE Trans-Zeaxanthin Cis-Zeaxanthin GREEN (THIS MODEL IS STILL HYPOTHETICAL)

More Related