Quirin wins the First Paper of the Year award. His study on the GNÜLLER GATAs is published online today in Plant Physiology.
Quirin wins the First Paper of the Year award. His study on the GNÜLLER GATAs is published online today in Plant Physiology.
Ranftl Q. L., Bastakis E., Klermund C., and Schwechheimer C. (2016). "LLM-domain containing B-GATA factors control different aspects of cytokinin-regulated development in Arabidopsis thaliana", Plant Physiology 2016 : pp.15.01556v1-pp.01556.2015.
LLM-domain B-GATAs are a subfamily of the thirty-membered GATA transcription factor family from Arabidopsis thaliana. Only two of the six Arabidopsis LLM-domain B-GATAs, GNC (GATA, NITRATE-INDUCIBLE, CARBON METABOLISM-INVOLVED) and its paralog GNL/CGA1 (GNC-LIKE/CYTOKININ-RESPONSIVE GATA FACTOR1), have already been analyzed with regard to their biological function. Together, GNC and GNL control germination, greening, flowering time, and senescence downstream from auxin, CK (cytokinin), gibberellin, and light signaling. Whereas overexpression and complementation analyses suggest a redundant biochemical function between GNC and GNL, nothing is known about the biological role of the four other LLM-domain B-GATAs, GATA15, GATA16, GATA17 and GATA17L (GATA17-LIKE), based on loss-of-function mutant phenotypes. Here, we examine insertion mutants of the six Arabidopsis B-GATA genes and reveal the role of these genes in the control of greening, hypocotyl elongation, phyllotaxy, floral organ initiation, accessory meristem formation, flowering time and senescence. Several of the respective responses may be mediated by CK signaling, which activates the expression of all six GATA genes. In line with an important role of the B-GATAs in CK responses, we show that CK-induced gene expression is partially compromised in LLM-domain B-GATA gene mutants. We furthermore provide evidence for a transcriptional cross-regulation between these GATAs that may, in at least some cases, be at the basis of their apparent functional redundancy.