Disease relevance of DREB2A

• Expression of the DREB1A gene and its two homologs was induced by low-temperature stress, whereas expression of the DREB2A gene and its single homolog was induced by dehydration [1].
• Moreover, the transcriptional induction of DREB2 (dehydration responsive element-binding factor 2) subfamily genes and COR47/rd17 under heat stress suggested cross-talk between the signaling pathways for heat and dehydration responses [2].

High impact information on DREB2A

• However, some genes downstream of DREB2A are not downstream of DREB1A, which also recognizes DRE/CRT but functions in cold stress-responsive gene expression [3].
• Functional Analysis of an Arabidopsis Transcription Factor, DREB2A, Involved in Drought-Responsive Gene Expression [3].
• Intact DREB2A expression does not activate downstream genes under normal growth conditions, suggesting that DREB2A requires posttranslational modification for activation, but the activation mechanism has not been clarified [3].
• DREB2A domain analysis using Arabidopsis protoplasts identified a transcriptional activation domain between residues 254 and 335, and deletion of a region between residues 136 and 165 transforms DREB2A to a constitutive active form [3].
• These results indicate that two independent families of DREB proteins, DREB1 and DREB2, function as trans-acting factors in two separate signal transduction pathways under low-temperature and dehydration conditions, respectively [1].

Biological context of DREB2A

• Both the DREB1A and DREB2A proteins specifically bound to the DRE sequence in vitro and activated the transcription of the b-glucuronidase reporter gene driven by the DRE sequence in Arabidopsis leaf protoplasts [1].
• The deduced amino acid sequences of DREB1A and DREB2A showed no significant sequence similarity, except in the conserved DNA binding domains found in the EREBP and APETALA2 proteins that function in ethylene-responsive expression and floral morphogenesis, respectively [1].
• In this study, a cDNA with an open reading frame of 332 amino acids, encoding the transcription activation factor DREB2A, was cloned from Pennisetum glaucum, a stress tolerant food grain crop [4].
• The present data indicate that stress induction of genes could occur via post-translational modification by phosphorylation of DREB2A [4].
• Stress-inducible DREB2A transcription factor from Pennisetum glaucum is a phosphoprotein and its phosphorylation negatively regulates its DNA-binding activity [4].

Associations of DREB2A with chemical compounds

• Furthermore, DREB2A expression was salicylic acid (SA) dependent but NPR (non-expressor of PR genes)1 independent [5].

Other interactions of DREB2A

• TTL1 regulates the transcript levels of several dehydration-responsive genes, such as the transcription factor DREB2A, and genes encoding dehydration response proteins, such as ERD1 (early response to dehydration 1), ERD3, and COR15a [6].
• The DREB2A gene is located on chromosome 5, and DREB2B on chromosome 3 [7].

Analytical, diagnostic and therapeutic context of DREB2A

• We carried out microarray analysis of transgenic Arabidopsis-overexpressing DREB2A CA and found that the overexpression of DREB2A CA induces not only drought- and salt-responsive genes but also heat-shock (HS)-related genes [8].

References