title: Root-shoot interaction in the greening of wheat seedlings grown under red light.
abstract: Wheat seedlings grown with roots exposed to constant red light (300-500 micromoles m-2 s-1) did not accumulate chlorophyll in the leaves. In contrast, seedlings grown with their roots shielded from light accumulated chlorophylls. Chlorophyll biosynthesis could be induced in red-light-grown chlorophyll-deficient yellow plants by either reducing the red-light intensity at the root surface to 100 micromoles m-1 s-1 or supplementing with 6% blue light. The inhibition of chlorophyll biosynthesis was due to impairment of the Mg-chelatase enzyme working at the origin of the Mg-tetrapyrrole pathway. The root-perceived photomorphogenic inhibition of shoot greening demonstrates root-shoot interaction in the greening process.
authors.affiliation: National Aeronautics and Space Administration, Kennedy Space Center, Florida 32899, USA.
authors.forename: B C
authors.initials: BC
authors.lastname: Tripathy
authors.forename: C S
authors.initials: CS
authors.lastname: Brown
mesh_terms: D002734:Chlorophyll / Q000096:biosynthesis*; D004307:Dose-Response Relationship, Radiation; D005069:Evaluation Studies as Topic; D018525:Germination / Q000528:radiation effects; D008027:Light; D008029:Lighting; D008190:Lyases / Q000378:metabolism; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects; D018517:Plant Roots / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects; D018520:Plant Shoots / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects; D011521:Protochlorophyllide / Q000096:biosynthesis; D011524:Protoporphyrins / Q000096:biosynthesis; D014908:Triticum / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects
chemical_list: D011524:Protoporphyrins; D002734:Chlorophyll; C039629:magnesium protoporphyrin; C033434:protoporphyrin IX monomethyl ester; D011521:Protochlorophyllide; D008190:Lyases; C086788:magnesium chelatase