QLQ

• SMART accession number: SM00951
• Description: QLQ is named after the conserved Gln, Leu, Gln motif. QLQ is found at the N-terminus of SWI2/SNF2 protein, which has been shown to be involved in protein-protein interactions. QLQ has been postulated to be involved in mediating protein interactions (PUBMED:12974814).
• Interpro abstract (IPR014978):

  The QLQ domain is characterised by the conserved Gln-Leu-Gln residues. Another feature of this domain is the absolute conservation of bulky aromatic/hydrophobic and acidic amino acid residues such as Phe, Trp, Tyr, Leu, Glu, or their equivalents in terms of chemical and radial properties. The Pro residue is also absolutely conserved. These amino acid residues are critical for the function of the QLQ domain, probably for protein-protein interaction [ (PUBMED:12974814) ].

  Some proteins known to conatin a QLQ domain are listed below:

  • Plant GROWTH-REGULATING FACTOR (GRF) proteins, putative transcription factors.
  • Eukaryotic SWI2/SNF2, transcriptional coactivators.
• GO process: regulation of transcription, DNA-templated (GO:0006355)
• GO component: nucleus (GO:0005634)
• GO function: ATP binding (GO:0005524)

There are 3266 QLQ domains in 3253 proteins in SMART's nrdb database.

Cellular role (predicted cellular role)

Cellular role: interaction

Literature (relevant references for this domain)

Primary literature is listed below; Automatically-derived, secondary literature is also avaliable.

• Kim JH, Choi D, Kende H
• The AtGRF family of putative transcription factors is involved in leaf andcotyledon growth in Arabidopsis.
• Plant J. 2003; 36: 94-104

Previously, we identified a novel rice gene, GROWTH-REGULATING FACTOR1(OsGRF1), which encodes a putative transcription factor that appears toplay a regulatory role in stem elongation. We now describe the GRF genefamily of Arabidopsis thaliana (AtGRF), which comprises nine members. Thededuced AtGRF proteins contain the same characteristic regions--the QLQ(Gln, Leu, Gln) and WRC (Trp, Arg, Cys) domains--as do OsGRF1 and relatedproteins in rice, as well as features indicating a function intranscriptional regulation. Most of the AtGRF genes are strongly expressedin actively growing and developing tissues, such as shoot tips, flowerbuds, and roots, but weakly in mature stem and leaf tissues.Overexpression of AtGRF1 and AtGRF2 resulted in larger leaves andcotyledons, as well as in delayed bolting of the inflorescence stem whencompared to wild-type plants. In contrast, triple insertional null mutantsof AtGRF1-AtGRF3 had smaller leaves and cotyledons, whereas single mutantsdisplayed no changes in phenotype and double mutants displayed only minorones. The alteration of leaf growth in overexpressors and triple mutantswas based on an increase or decrease in cell size, respectively. Theseresults indicate that AtGRF proteins play a role in the regulation of cellexpansion in leaf and cotyledon tissues.

Links (links to other resources describing this domain)

• INTERPRO: IPR014978
• PFAM: QLQ