RESUMO
BACKGROUND: The AP2/ERF transcription factor family plays important roles in regulation of plant growth and development as well as the response of plants to stress. However, there are currently few studies focusing on the function of the AP2/ERF-type transcription factors in Caragana intermedia Kuang et H. C. Fu. Here, the expression pattern of AP2/ERF transcription factors family in different tissues and under four stress treatments were evaluated, and the function of CiDREB3 was examined. METHODS AND RESULTS: In this study, the genes encoding the AP2/ERF family of transcription factors were screened from the C. intermedia drought transcriptome database and subjected to bioinformatic analysis using the online tool and software. The expression pattern of the members of AP2/ERF transcription factors in C. intermedia were detected via quantitative real-time PCR (qRT-PCR). The function of CiDREB3 on growth, development and drought tolerance was evaluated by transgenic Arabidopsis. As a result, 22 sequences with complete ORFs were obtained and all sequences were divided into 13 sub-groups. Most of the AP2/ERF transcription factors exhibited tissue-specific expression and were induced by cold, heat, NaCl and mannitol treatments. Furthermore, heterologous expression of CiDREB3 altered the morphology of the transgenic Arabidopsis thaliana L. Heynh and improved its drought tolerance during seedlings development. CONCLUSIONS: Taken together, the results of the present study helped to better understand the function of the AP2/ERF family transcription factors in response to multiple abiotic stresses and uncovered the role of CiDREB3 in affecting the morphology and abiotic stress tolerance of Arabidopsis.
Assuntos
Caragana/genética , Proteínas de Ligação a DNA/genética , Fator de Transcrição AP-2/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Caragana/metabolismo , Caragana/fisiologia , Proteínas de Ligação a DNA/metabolismo , Secas , Evolução Molecular , Expressão Gênica/genética , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Fator de Transcrição AP-2/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/genéticaRESUMO
BACKGROUND: Domain of unknown function (DUF) proteins represent a number of gene families that encode functionally uncharacterized proteins in eukaryotes. The DUF4228 gene family is one of these families in plants that has not been described previously. RESULTS: In this study, we performed an extensive comparative analysis of DUF4228 proteins and determined their phylogeny in the plant lineage. A total of 489 high-confidence DUF4228 family members were identified from 14 land plant species, which sub-divided into three distinct phylogenetic groups: group I, group II and group III. A highly conserved DUF4228 domain and motif distribution existed in each group, implying their functional conservation. To reveal the possible biological functions of these DUF4228 genes, 25 ATDUF4228 sequences from Arabidopsis thaliana were selected for further analysis of characteristics such as their chromosomal position, gene duplications and gene structures. Ka/Ks analysis identified seven segmental duplication events, while no tandemly duplication gene pairs were found in A. thaliana. Some cis-elements responding to abiotic stress and phytohormones were identified in the upstream sequences of the ATDUF4228 genes. Expression profiling of the ATDUF4228 genes under abiotic stresses (mainly osmotic, salt and cold) and protein-protein interaction prediction suggested that some ATDUF4228 genes are may be involved in the pathways of plant resistance to abiotic stresses. CONCLUSION: These results expand our knowledge of the evolution of the DUF4228 gene family in plants and will contribute to the elucidation of the biological functions of DUF4228 genes in the future.
Assuntos
Embriófitas/genética , Genômica , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Arabidopsis/genética , Cromossomos de Plantas/genética , Duplicação Gênica/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Filogenia , Alinhamento de SequênciaRESUMO
UNLABELLED: Calmodulin-binding proteins (CBPs) have been known to be involved in both biotic and abiotic stress responses. Recently, two closely related CBPs, Arabidopsis SAR Deficient 1 and CBP60g, were found to belong to a new family of transcription factors that regulate salicylic acid (SA) biosynthesis triggered by microbe-associated molecular patterns. In this study, we found that overexpression of CBP60g in Arabidopsis caused elevated SA accumulation, increased expression of the defense genes, and enhanced resistance to Pseudomonas syringae. In addition to the enhanced defense response, the CBP60g overexpression lines showed hypersensitivity to abscisic acid (ABA) and enhanced tolerance to drought stress. We also found that treatment with ABA and drought stress leads to a higher expression level of the ICS1 gene, which encodes isochorismate synthase, in the CBP60g overexpression lines than in the wild-type control plants. Our results suggest that CBP60g serves as a molecular link that positively regulates ABA- and SA-mediated pathways in plants. KEY MESSAGE: Overexpression of CBP60g in Arabidopsis enhanced the defense response, hypersensitivity to abscisic acid and tolerance to drought stress.