Journal Article

A Myb-related transcription factor is involved in the phytochrome regulation of an Arabidopsis Lhcb gene

Wang, Z.Y. (University of California, Los Angeles, CA.), Sun, L, Tobin, E.M, Harel, E, Kenigsbuch, D, Ong, M.S

1997

Overview

We have isolated the gene for a protein designated CCA1. This protein can bind to a region of the promoter of an Arabidopsis light-harvesting chlorophyll a/b protein gene, Lhcb1*3, which is necessary for its regulation by phytochrome. The CCA1 protein interacted with two imperfect repeats in the Lhcb1*3 promoter, AA(A/C)AATCT, a sequence that is conserved in Lhcb genes. A region near the N terminus of CCA1, which has some homology to the repeated sequence found in the DNA binding domain of Myb proteins, is required for binding to the Lhcb1*3 promoter. Lines of transgenic Arabidopsis plants expressing antisense RNA for CCA1 showed reduced phytochrome induction of the endogenous Lhcb1*3 gene, whereas expression of another phytochrome-regulated gene, rbcS-1A, which encodes the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase, was not affected. Thus, the CCA1 protein acts as a specific activator of Lhcb1*3 transcription in response to brief red illumination. The expression of CCA1 RNA was itself transiently increased when etiolated seedlings were transferred to light. We conclude that the CCA1 protein is a key element in the functioning of the phytochrome signal transduction pathway leading to increased transcription of this Lhcb gene in Arabidopsis

• Publisher: American Society of Plant Physiologists
• Subject: ADN / AHILAMIENTO / Amino Acid Sequence / amino acid sequences / antisense RNA / Arabidopsis / Arabidopsis - genetics / Arabidopsis Proteins / ARABIDOPSIS THALIANA / ARN / Base Sequence / Carrier Proteins / Carrier Proteins - genetics / CHLOROPHYLLE / Cloning, Molecular / CLOROFILAS / Complementary DNA / COMPOSICION QUIMICA / COMPOSITION CHIMIQUE / Conserved Sequence / DNA / DNA probes / DNA, Complementary / DNA-binding proteins / etiolation / ETIOLEMENT / FITOCROMA / Gels / GENE / Gene expression regulation / Gene Expression Regulation, Plant / GENES / GENETICA / genetics / GENETIQUE / Light-Harvesting Protein Complexes / LUMIERE / LUZ / metabolism / Molecular Sequence Data / Photosynthetic Reaction Center Complex Proteins / Photosystem II Protein Complex / physiology / PHYTOCHROME / Phytochrome - physiology / Plant cells / Plant Proteins / PLANTAS TRANSGENICAS / PLANTE TRANSGENIQUE / PLANTULAS / PLANTULE / Promoter regions / Promoter Regions, Genetic / PROTEINAS AGLUTINANTES / PROTEINE DE LIAISON / Proteins / Proto-Oncogene Proteins / Proto-Oncogene Proteins - metabolism / Proto-Oncogene Proteins c-myb / red light / regulator genes / RNA / SECUENCIA NUCLEOTIDICA / seedlings / Sequence Homology, Amino Acid / SEQUENCE NUCLEOTIDIQUE / TRANSCRIPCION / TRANSCRIPTION / transcription (genetics) / transcription factors / Transcription Factors - metabolism / transgenic plants