Displaying GeBP Family from Sorghum


INFORMATION ABOUT GeBP FAMILY

Trichomes of Arabidopsis are single-celled epidermal hair that are a useful model for studying plant cell fate determination. Trichome initiation requires the activity of the GLABROUS1 (GL1) gene whose expression in epidermal and trichome cells is dependent on the presence of a 3'-cis-regulatory element. Using a one-hybrid screen, we have isolated a cDNA, which encodes for a protein, GL1 enhancer binding protein (GeBP), that binds this regulatory element in yeast and in vitro. GeBP and its three homologues in Arabidopsis share two regions: a central region with no known motifs and a C-terminal region with a putative leucine-zipper motif. We show that both regions are necessary for trans-activation in yeast. A translational fusion with the Yellow Fluorescent Protein (YFP) indicates that GeBP is a nuclear protein whose localization is restricted to, on average, 3-5 subnuclear foci that might correspond to nucleoli. Transcriptional fusion with the GUS reporter indicates that GeBP is mainly expressed in vegetative meristematic tissues and in very young leaf primordia. We looked at GeBP expression in plants mutated in or misexpressing KNAT1, a KNOX gene, expressed in the shoot apical meristem and downregulated in leaf founder cells, and found that GeBP transcript level is regulated by KNAT1 suggesting that KNAT1 is a transcriptional activator of GeBP. This regulation suggests that GeBP is acting as a repressor of leaf cell fate.


Protein Name
accepted / suggested
Gene Locus Synonym/
Gene Name
Clone in TFome Genome Browser
SbGBP1 Sb01g006270 View in Browser
SbGBP2 Sb01g010570 View in Browser
SbGBP3 Sb01g024673 View in Browser
SbGBP4 Sb01g034370 View in Browser
SbGBP5 Sb02g026310 View in Browser
SbGBP6 Sb02g040550 View in Browser
SbGBP7 Sb03g005180 View in Browser
SbGBP8 Sb03g009480 View in Browser
SbGBP9 Sb04g034350 View in Browser
SbGBP10 Sb04g034360 View in Browser
SbGBP11 Sb04g034370 View in Browser
SbGBP12 Sb04g034490 View in Browser
SbGBP13 Sb06g000610 View in Browser
SbGBP14 Sb07g022740 View in Browser
SbGBP15 Sb10g006920 View in Browser