The transcript abundance of GmGT-2, a new member of the GT-2 family of transcription factors from soybean, is down-regulated by light in a phytochrome-dependent manner.
A new member of the GT-2 family of transcription factors, GmGT-2, was isolated from soybean while screening a cDNA library with a protein binding site (D1) in the promoter of Aux28, a member of the Aux/IAA family of auxin-responsive genes. GmGT-2 possesses various primary amino acid sequence characteristics common to all GT-2 factors thus far isolated, including sequence identity in the twin trihelix DNA-binding domains. Recombinant GmGT-2 expressed in Escherichia coli binds oligotetramers of both D1 and various GT-boxes. However, unlike other known members of the GT-2 family, GmGT-2 message levels are down-regulated by light in a phytochrome-dependent manner. Evidence is presented that the expression levels of Aux28 mRNA are also down-regulated by phytochrome. These results and other referenced data implicate the possible convergence of phytochrome and auxin signaling pathways.
O'Grady
K
K
Department of Botany, University of Georgia, Athens 30602-7229, USA. ogrady@dogwood.botany.uga.edu
Goekjian
V H
VH
Naim
C J
CJ
Nagao
R T
RT
Key
J L
JL
D000595:Amino Acid Sequence; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D018507:Gene Expression Regulation, Developmental / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D018546:Hypocotyl / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D007210:Indoleacetic Acids / Q000494:pharmacology; D008027:Light; D008969:Molecular Sequence Data; D010834:Phytochrome / Q000502:physiology*; D010940:Plant Proteins / Q000187:drug effects / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics; D011485:Protein Binding / Q000528:radiation effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013025:Glycine max / Q000235:genetics* / Q000254:growth & development; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D018076:DNA, Complementary; D018744:DNA, Plant; D004268:DNA-Binding Proteins; C437066:GmGT-2 protein, Glycine max; D007210:Indoleacetic Acids; D010940:Plant Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D010834:Phytochrome