title: Genetic regulation of cold-induced albinism in the maize inbred line A661.
abstract: In spite of multiple studies elucidating the regulatory pathways controlling chlorophyll biosynthesis and photosynthetic activity, little is known about the molecular mechanism regulating cold-induced chlorosis in higher plants. Herein the characterization of the maize inbred line A661 which shows a cold-induced albino phenotype is reported. The data show that exposure of seedlings to low temperatures during early leaf biogenesis led to chlorophyll losses in this inbred. A661 shows a high plasticity, recovering resting levels of photosynthesis activity when exposed to optimal temperatures. Biochemical and transcriptome data indicate that at suboptimal temperatures chlorophyll could not be fully accommodated in the photosynthetic antenna in A661, remaining free in the chloroplast. The accumulation of free chlorophyll activates the expression of an early light inducible protein (elip) gene which binds chlorophyll to avoid cross-reactions that could lead to the generation of harmful reactive oxygen species. Higher levels of the elip transcript were observed in plants showing a cold-induced albino phenotype. Forward genetic analysis reveals that a gene located on the short arm of chromosome 2 regulates this protective mechanism.
authors.affiliation: Misión Biológica de Galicia (MBG-CSIC), Apartado 28, E-36080 Pontevedra, Spain. vmrodriguez@mbg.csic.es
authors.forename: Víctor M
authors.initials: VM
authors.lastname: Rodríguez
authors.forename: Pablo
authors.initials: P
authors.lastname: Velasco
authors.forename: José L
authors.initials: JL
authors.lastname: Garrido
authors.forename: Pedro
authors.initials: P
authors.lastname: Revilla
authors.forename: Amando
authors.initials: A
authors.lastname: Ordás
authors.forename: Ana
authors.initials: A
authors.lastname: Butrón
mesh_terms: D002734:Chlorophyll / Q000235:genetics* / Q000378:metabolism; D003080:Cold Temperature; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D007178:Inbreeding; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D010858:Pigmentation; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D003313:Zea mays / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D010940:Plant Proteins; D002734:Chlorophyll
keywords: Albinism; Zea mays.; chlorophyll biosynthesis; cold; early light inducible protein (elip); photosystem