Expression patterns within the Arabidopsis C/S1 bZIP transcription factor network: availability of heterodimerization partners controls gene expression during stress response and development.
Members of the Arabidopsis group C/S1 basic leucine zipper (bZIP) transcription factor (TF) network are proposed to implement transcriptional reprogramming of plant growth in response to energy deprivation and environmental stresses. The four group C and five group S1 members form specific heterodimers and are, therefore, considered to cooperate functionally. For example, the interplay of C/S1 bZIP TFs in regulating seed maturation genes was analyzed by expression studies and target gene regulation in both protoplasts and transgenic plants. The abundance of the heterodimerization partners significantly affects target gene transcription. Therefore, a detailed analysis of the developmental and stress related expression patterns was performed by comparing promoter: GUS and transcription data. The idea that the C/S1 network plays a role in the allocation of nutrients is supported by the defined and partially overlapping expression patterns in sink leaves, seeds and anthers. Accordingly, metabolic signals strongly affect bZIP expression on the transcriptional and/or post-transcriptional level. Sucrose induced repression of translation (SIRT) was demonstrated for all group S1 bZIPs. In particular, transcription of group S1 genes strongly responds to various abiotic stresses, such as salt (AtbZIP1) or cold (AtbZIP44). In summary, heterodimerization and expression data provide a basic framework to further determine the functional impact of the C/S1 network in regulating the plant energy balance and nutrient allocation.
Weltmeier
Fridtjof
F
Albrecht-von-Haller-Institut, Universität Göttingen, Untere Karspüle 2, D-37073 Göttingen, Germany.
Rahmani
Fatima
F
Ehlert
Andrea
A
Dietrich
Katrin
K
Schütze
Katia
K
Wang
Xuan
X
Chaban
Christina
C
Hanson
Johannes
J
Teige
Markus
M
Harter
Klaus
K
Vicente-Carbajosa
Jesus
J
Smeekens
Sjef
S
Dröge-Laser
Wolfgang
W
D017360:Arabidopsis / Q000235:genetics*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics*; D019281:Dimerization; D018506:Gene Expression Regulation, Plant; D013312:Stress, Physiological
D050976:Basic-Leucine Zipper Transcription Factors