ABSTRACT
Phytopathogenic microorganisms have a significant influence on survival and productivity of several crop plants. Transcription factors (TFs) are important players in the response to biotic stresses, as insect attack and pathogen infection. In face of such adversities many TFs families have been previously reported as differentially expressed in plants as a reaction to bacterial, fungal and viral infection. This review highlights recent progresses in understanding the structure, function, signal regulation and interaction of transcription factors with other proteins in response to pathogens. Hence, we focus on three families of transcription factors: ERF, bZIP and WRKY, due to their abundance, importance and the availability of functionally well-characterized members in response to pathogen attack. Their roles and the possibilities related to the use of this knowledge for engineering pathogen resistance in crop plants are also discussed.
Subject(s)
Arabidopsis Proteins/immunology , Basic-Leucine Zipper Transcription Factors/immunology , DNA-Binding Proteins/immunology , Disease Resistance/genetics , Plant Diseases/immunology , Plant Proteins/immunology , Plants/genetics , Transcription Factors/immunology , Arabidopsis Proteins/genetics , Basic-Leucine Zipper Transcription Factors/genetics , DNA-Binding Proteins/genetics , Gene Expression Regulation, Plant/immunology , Host-Pathogen Interactions/genetics , Host-Pathogen Interactions/immunology , Plant Diseases/genetics , Plant Immunity/genetics , Plant Proteins/genetics , Plants/immunology , Plants/microbiology , Plants/virology , Plants, Genetically Modified , Protein Interaction Mapping , Protein Isoforms/genetics , Protein Isoforms/immunology , Signal Transduction , Stress, Physiological/genetics , Stress, Physiological/immunology , Transcription Factors/genetics , Transcription, GeneticABSTRACT
Podocarpus sellowii (Podocarpaceae) is one of only a few gymnosperms native to Brazil and the sole species of the genus found in the northeastern region of that country. It has a very restricted distribution in this region, with only three known populations in highland forests (called Brejos de Altitude), which apparently have been isolated from each other since the Pleistocene. Due to this long-term isolation and the fact that these populations have few adult individuals and suffer great anthropogenic pressure, low genetic variability is expected, compromising their long-term viability. The present work assessed the genetic variability and structure of northeastern populations of P. sellowii to investigate the role of Pleistocene glaciations on the genetic relationships between them and to propose strategies for their conservation by analyzing the SSR and ISSR markers of adult and juvenile individuals. Low genetic diversity was found with both markers, associated with a high differentiation of the Brejo de Baturité population in relation to the others-suggesting their isolation at different points in time, probably during the Pleistocene. Actions directed towards increasing the genetic diversity of these populations will be needed, such as planting seedlings with high genetic variability-but the high degrees of differentiation observed between the populations must be taken into account.
