GARP-G2-like Transcription Factor Family
he GLK proteins are members of the recently categorized GARP superfamily of
transcription factors (Riechmann et al., 2000) defined by G2 in maize; the
Arabidopsis RESPONSE REGULATOR-B (ARR-B) proteins (Imamura et al., 1999); and
the PHOSPHATE STARVATION RESPONSE1 (PSR1) protein of Chlamydomonas (Wykoff et
al., 1999). In the case of G2, three of the four defining features of most
transcription factors have been verified experimentally in heterologous systems.
G2 is nuclearlocalized (Hall et al., 1998), is able to transactivate reporter
gene expression, and can both homo-dimerize and heterodimerize with ZmGLK1
(Rossini et al., 2001). DNA-binding activity of GLK proteins has yet to be
demonstrated,however, the putative DNA-binding domain is highly conserved with
domains in other GARP proteins such as ARR1 and ARR2 (Riechmann et al., 2000).
Notably, ARR1 and ARR2 have been shown to bind DNA (Sakai et al.,2000), thus it
is likely that GLK proteins act as transcriptional regulators of chloroplast
development.
The GLK proteins are members of the GARP superfamily of transcription factors,
and phylogenetic analysis demonstrates that the maize, rice and Arabidopsis GLK
gene pairs comprise a distinct group within the GARP superfamily. Further
phylogenetic analysis suggests that the gene pairs arose through separate
duplication events in the monocot and dicot lineages. As in rice, AtGLK1 and
AtGLK2 are expressed in partially overlapping domains in photosynthetic tissue.
GLK genes therefore regulate chloroplast development in diverse plant species
(taken from
PlantTFDB).
Notes: GARP-G2-like is missed in TOBFAC.
143 predicted putative GARP-G2-like TF peptide,
CDS, and cDNA sequences;
blast HSP, and multiple sequence alignment in
Soy - TFKB.
G2-like domain peptide sequences with alignment
and phylogeny tree.
43 GARP-G2-like protein and DNA sequences with
annotations for soybean in PlantTFDB. Most are partial sequences.
Last updated by Dr. Jeff Chen
on July 20, 2009.
