High impact information on ATHB-2

• Transgenic plants bearing constructs that alter HAT4 expression exhibit a series of interesting developmental phenotypes, including changes in morphology and developmental rate [1].
• Point mutants of HAT4 isolated in yeast define functionally critical residues within the HD-Zip domain, many of which correspond to highly conserved positions in known homeo domains and leucine zippers [1].
• Thus, the HAT4 gene of Arabidopsis encodes an HD-Zip protein that functions as a novel developmental regulator [1].
• The HAT4 gene from the plant Arabidopsis thaliana encodes a homeo domain protein that contains a leucine zipper motif [1].
• The action of ATHB-2 is likely to generate changes in auxin distribution that produce distinct but coordinated effects on different cell types across the plant [2].

Biological context of ATHB-2

• We also show that reduced levels of ATHB-2 result in reciprocal phenotypes [3].
• Moreover, we demonstrate that ATHB-2 functions as a negative regulator of gene expression in a transient assay [3].
• In the root and hypocotyl, elevated ATHB-2 levels also inhibit specific cell proliferation such as secondary growth of the vascular system and lateral root formation [3].
• To understand how ATHB-2 mediates light signals in plant morphogenesis, we investigated its transcriptional network [4].
• Negative autoregulation of the Arabidopsis homeobox gene ATHB-2 [4].

Associations of ATHB-2 with chemical compounds

• Interestingly, we found that ATHB-2-induced, as well as shade-induced, elongation of the hypocotyl is dependent on the auxin transport system [3].

Other interactions of ATHB-2

• The ATHB-2 gene encoding an homeodomain-leucine zipper protein is rapidly and strongly induced by changes in the ratio of red to far-red light which naturally occur during the daytime under the canopy and induce in many plants the shade avoidance response [3].
• The creation of triple and quadruple mutants in Arabidopsis, deficient in multiple phytochromes, has revealed functional redundancy between phyB, D, and E in controlling flowering time, leaf development, and regulation of the homeobox gene, ATHB-2 [5].

References