- ABA treatment induced the increases in the expression of ZFP182, OsMPK1 and OsMPK5, and the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) in rice leaves. The transient gene expression analysis and the transient RNA interference (RNAi) analysis in protoplasts showed that ZFP182, OsMPK1 and OsMPK5 are involved in ABA-induced up-regulation in the activities of SOD and APX. Besides, OsMPK1 and OsMPK5 were shown to be required for the up-regulation in the expression of ZFP182 in ABA signaling, but ZFP182 did not mediate the ABA-induced up-regulation in the expression of OsMPK1 and OsMPK5, which indicate that ZFP182 is required for ABA-induced antioxidant defense and the expression of ZFP182 is regulated by rice MAPKs in ABA signaling.
- Overexpression of ZFP182 promotes accumulation of compatible osmolytes, such as free proline and soluble sugars, in transgenic rice. ZFP182 activates the expression of OsP5CS encoding pyrroline-5-carboxylate synthetase and OsLEA3 under stress conditions, while OsDREB1A and OsDREB1B were regulated by ZFP182 under both normal and stress conditions.
- The seedlings of ZFP182-ox lines, ZFP182-kd and WT were watered with 500 ml of 100 mM NaCl for 14 days.(Fig 1A)
- The ZFP182 transgenic plants and wild-type plants were treated at 4℃ for 4 days and then recovered at 25℃ for 7 days.(Fig 2A)
- The seedlings of ZFP182-ox lines, ZFP182-kd and WT at the four-leaf stage were not watered for 14 days followed by 7 days of rewatering.(Fig 3A)
- ZFP182 was constitutively and weakly expressed in leaves, culms, roots, immature and flowering spikes. The expression of ZFP182 in the rice seedlings under several stresses: expression of ZFP182 was significantly induced under cold stress, and reached the maximum level at 12 h after treatment. Accumulation of ZFP182 transcripts was markedly increased in rice seedlings after 6 h treatment of 150 mM NaCl and exogenous 0.1 mM ABA treatment and maintained the constant up to 24 h,which suggesting that ZFP182 might be involved in cold and salt stress responses and its mediated signaling transduction might be ABA dependent.
- Induction of GUS expression in transgenic tobacco by salt stress resulted from ion stress not by osmotic. ZFP182 promoter was also responsive to KCl treatment, but not to MgCl2, CdCl2, and ZnSO4 stresses (data notshown). ZFP182 promoter might be specifically responsive to monovalent cation ionophores.
- Overexpression of ZFP182 in rice confers tolerance to salt stress: survival rates of ZFP182-ox transgenic lines (~50–60 %) were significantly higher than those of WT plants (~15 %) and ZFP182-kd lines (~12–16 %), after 14 days of salt stress (Fig. 1).
- Overexpression of ZFP182 enhances cold tolerance in rice:
After cold treatment, it was observed that the survival rates of ZFP182-ox transgenic lines (~80 %) were significantly higher than those of WT plants (~17 %) and ZFP182-kd lines (~17 %)(Fig. 2).
- Overexpression of ZFP182 enhances drought tolerance in rice:
For drought stress, it was found that the survival rates of ZFP182-ox lines (~80 %) were significantly higher than those of WT plants (~22 %) and ZFP182-kd lines (~16 %) after drought treatment (Fig. 3). ZFP182-ox improved tolerance to salt, cold and drought stresses in rice. Interestingly, knock-down of ZFP182 expression didn’t largely affect abioitc stress tolerance of transgenic rice (Figs. 1, 2, 3).
- A phylogenetic tree was constructed using neighbor-joining method with the full-length amino acid sequences To investigate the evolutionary relationship among plant C2H2-type zinc finger proteins involved in stress responses, (Fig. 4). The result revealed that ZFP182 was clustered with ZAT12, an Arabidopsis stress responsive zinc finger protein, whereas other stress responsive zinc finger proteins were categorized into another big branch.
- To investigate the evolutionary relationship among plant C2H2-type zinc finger proteins involved in stress responses, a phylogenetic tree was constructed using Neighbor–Joining method with the full-length amino acid sequences (Fig. 1B)..The result revealed that ZFP179 was clustered with ZFP182, ZFP150, and ZAT12, whereas other stress responsive zinc finger proteins were categorized into another big branch.
The full-length ZFP182 was in-frame fused with GFP reporter gene (35S:ZFP182-GFP) and transiently expressed in onion epidermal cells. As expected, ZFP182-GFP fusion protein was fully localized to the nucleus. ZFP182 forms homodimer in plant nucleus and may function as a transcription factor..
- Some members of C2H2-type ZFPs are important regulators of ROS signaling and can integrate ROS signaling with responses to abiotic stresses. However, it is not clear whether these members of C2H2-type ZFPs are involved in ABA-induced antioxidant defense and if so, what the relationship between the C2H2-type ZFPs and MAPK in the ABA signaling is.
- A number of TFIIIA-type zinc finger proteins were shown to be involved in stress response such as Arabidopsis STZ/ZAT10 and ZAT7 which are involved in salt tolerance, soybean SCOF-1 which plays a role in cold tolerance, Arabidopsis ZAT12 involved in cold and oxidative stressand ZPT2-3, which mediates drought tolerance in petunia. Recently, a new member of this family,GsZFP1, was identified in Glyycine soja and showed the ability in improving cold and drought tolerance.
- C2H2 proteins belong to a group of transcription factors (TFs) existing as a superfamily that plays important roles in defense responses and various other physiological processes in plants. C2H2 ZFPs constitute one of the largest TF families in plants, and their presence has been reported in several plant species, including Arabidopsis, petunia, rice, wheat, soybean, and pepper.
Labs working on this gene
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- Zhang H, Ni L, Liu Y, et al. The C2H2‐type Zinc Finger Protein ZFP182 is Involved in Abscisic Acid‐Induced Antioxidant Defense in RiceF[J]. Journal of integrative plant biology, 2012, 54(7): 500-510.
- Huang J, Yang X, Wang M M, et al. A novel rice C2H2-type zinc finger protein lacking DLN-box/EAR-motif plays a role in salt tolerance[J]. Biochimica et Biophysica Acta (BBA)-Gene Structure and Expression, 2007, 1769(4): 220-227.
- Huang J, Sun S, Xu D, et al. A TFIIIA-type zinc finger protein confers multiple abiotic stress tolerances in transgenic rice (Oryza sativa L.)[J]. Plant molecular biology, 2012, 80(3): 337-350.
- Davletova S, Schlauch K, Coutu J, et al. The zinc-finger protein Zat12 plays a central role in reactive oxygen and abiotic stress signaling in Arabidopsis[J]. Plant Physiology, 2005, 139(2): 847-856.
- Sun S J, Guo S Q, Yang X, et al. Functional analysis of a novel Cys2/His2-type zinc finger protein involved in salt tolerance in rice[J]. Journal of experimental botany, 2010: erq120.
- Jiang L, Pan L. Identification and expression of C2H2 transcription factor genes in Carica papaya under abiotic and biotic stresses[J]. Molecular biology reports, 2012, 39(6): 7105-7115.