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- Nagahage, Isura Sumeda Priyadarshana, et al.
(författare)
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An Arabidopsis NAC domain transcription factor, ATAF2, promotes age-dependent and dark-induced leaf senescence
- 2020
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Ingår i: Physiologia Plantarum. - : Blackwell Publishing. - 0031-9317 .- 1399-3054. ; 170:2, s. 299-308
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Tidskriftsartikel (refereegranskat)abstract
- Leaf senescence is controlled developmentally and environmentally and is affected by numerous genes, including transcription factors. An Arabidopsis NAC domain transcription factor, ATAF2, is known to regulate biotic stress responses. Recently, we have demonstrated that ATAF2 upregulates ORE1, a key regulator of leaf senescence. Here, to investigate the function of ATAF2 in leaf senescence further, we generated and analyzed overexpressing transgenic and T-DNA inserted mutant lines. Transient expression analysis indicated that ATAF2 upregulates several NAC domain transcription factors that regulate senescence. Indeed, ATAF2 overexpression induced the expression of senescence-related genes, thereby accelerating leaf senescence, whereas the expression of such genes in ataf2 mutants was lower than that of wild-type plants. Furthermore, the ataf2 mutants exhibited significant delays in dark-induced leaf senescence. It was also found that ATAF2 induces the expression of transcription factors, which both promotes and represses leaf senescence. The present study demonstrates that ATAF2 promotes leaf senescence in response to developmental and environmental signals.
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| 2. |
- Nagahage, Isura Sumeda Priyadarshana, et al.
(författare)
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NAC domain transcription factors VNI2 and ATAF2 form protein complexes and regulate leaf senescence
- 2023
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Ingår i: Plant Direct. - : John Wiley & Sons. - 2475-4455. ; 7:9
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Tidskriftsartikel (refereegranskat)abstract
- The NAM, ATAF1/2, and CUC2 (NAC) domain transcription factor VND-INTERACTING2 (VNI2) negatively regulates xylem vessel formation by interacting with another NAC domain transcription factor, VASCULAR-RELATED NAC-DOMAIN7 (VND7), a master regulator of xylem vessel formation. Here, we screened interacting proteins with VNI2 using yeast two-hybrid assay and isolated two NAC domain transcription factors, Arabidopsis thaliana ACTIVATION FACTOR 2 (ATAF2) and NAC DOMAIN CONTAINING PROTEIN 102 (ANAC102). A transient gene expression assay showed that ATAF2 upregulates the expression of genes involved in leaf senescence, and VNI2 effectively inhibits the transcriptional activation activity of ATAF2. vni2 mutants accelerate leaf senescence, whereas ataf2 mutants delay leaf senescence. In addition, the accelerated leaf senescence phenotype of the vni2 mutant is recovered by simultaneous mutation of ATAF2. Our findings strongly suggest that VNI2 interacts with and inhibits ATAF2, resulting in negatively regulating leaf senescence.
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