manshurica in resistant and susceptible genotypes. In total, 16 WRKY TFs were
differentially expressed in response to fungal inoculation. Furthermore, they
revealed that the GmWRKY31 bind to the W-box element present in the GmSAGT1
gene promoter region using the Y1H assay. Similarly, the negative role of
GhWRKY70 in resistance against V. dahlia was also elucidated (Xiong et al.
2019). More recently, barley HvWRKY6 and HvWRKY70 were validated to be a
key regulator between BTH- and NPR1-mediated acquired resistances by generating
heterologous overexpressed wheat transgenic lines followed by challenging with
P. striiformis f. sp. tritici and B. graminis f. sp. tritici (Li et al. 2020). The similar
results were obtained by overexpressing TaWRKY142 in transgenic Arabidopsis
plants against C. higginsianum (Kuki et al. 2020).
11.6 Conclusion
Plants are facing challenges from various phytopathogens for accurate plant growth
and development. In this chapter, we summarized and highlighted the regulation and
role of WRKY TFs in plant defense mechanism. Advancement in molecular
technologies in the last two decades enlightens the understanding in regulation and
role of WRKY TFs, this provides economic advantages to plant. Present information
of WRKY TFs can be implemented in the improvement of plant ideotypes, have
residence or tolerant against various phytopathogens. Overexpression or knockdown
of WRKY TFs in the early life of plant provides an opportunity for good growth and
development of plant with either resistance or tolerance against various
phytopathogens. Recent finding enlightens that regulation of various plant defense
genes by WRKY TFs is by regulating itself positively or negatively, auto- or crossregulation, by activation or suppression through other WRKY TFs or other
mechanisms regulated downstream plant defense genes. Regulation of WRKY TFs
is very complex phenomenon sine it requires to maintain harmony among entire
physiological and biochemical events within the plant. One WRKY TF can regulate
several defense or development process at a time, this cross-talk mechanism is
needed to be investigated. In the genomic era, study of entire genome of various
crops through transcriptomics and genomics help in better understanding of regulation of WRKY TFs against various plant diseases for strategic disease management.
Clustered regularly interspaced short palindromic repeats and their associated genes
can also allow manipulating the negatively controlled WRKY TFs genes functional
characterization of these WRKY TFs in defense. In addition, response of WRKY
TFs for various climatic challenges is to be studied and synchronization among
environmental factors and defense should be done.
References
Aamir M, Singh VK, Dubey MK, Kashyap SP, Zehra A, Upadhyay RS, Singh S (2018) Structural
and functional dissection of differentially expressed tomato WRKY transcripts in host defense
352
L. S. Rajput et al.
differentially expressed in response to fungal inoculation. Furthermore, they
revealed that the GmWRKY31 bind to the W-box element present in the GmSAGT1
gene promoter region using the Y1H assay. Similarly, the negative role of
GhWRKY70 in resistance against V. dahlia was also elucidated (Xiong et al.
2019). More recently, barley HvWRKY6 and HvWRKY70 were validated to be a
key regulator between BTH- and NPR1-mediated acquired resistances by generating
heterologous overexpressed wheat transgenic lines followed by challenging with
P. striiformis f. sp. tritici and B. graminis f. sp. tritici (Li et al. 2020). The similar
results were obtained by overexpressing TaWRKY142 in transgenic Arabidopsis
plants against C. higginsianum (Kuki et al. 2020).
11.6 Conclusion
Plants are facing challenges from various phytopathogens for accurate plant growth
and development. In this chapter, we summarized and highlighted the regulation and
role of WRKY TFs in plant defense mechanism. Advancement in molecular
technologies in the last two decades enlightens the understanding in regulation and
role of WRKY TFs, this provides economic advantages to plant. Present information
of WRKY TFs can be implemented in the improvement of plant ideotypes, have
residence or tolerant against various phytopathogens. Overexpression or knockdown
of WRKY TFs in the early life of plant provides an opportunity for good growth and
development of plant with either resistance or tolerance against various
phytopathogens. Recent finding enlightens that regulation of various plant defense
genes by WRKY TFs is by regulating itself positively or negatively, auto- or crossregulation, by activation or suppression through other WRKY TFs or other
mechanisms regulated downstream plant defense genes. Regulation of WRKY TFs
is very complex phenomenon sine it requires to maintain harmony among entire
physiological and biochemical events within the plant. One WRKY TF can regulate
several defense or development process at a time, this cross-talk mechanism is
needed to be investigated. In the genomic era, study of entire genome of various
crops through transcriptomics and genomics help in better understanding of regulation of WRKY TFs against various plant diseases for strategic disease management.
Clustered regularly interspaced short palindromic repeats and their associated genes
can also allow manipulating the negatively controlled WRKY TFs genes functional
characterization of these WRKY TFs in defense. In addition, response of WRKY
TFs for various climatic challenges is to be studied and synchronization among
environmental factors and defense should be done.
References
Aamir M, Singh VK, Dubey MK, Kashyap SP, Zehra A, Upadhyay RS, Singh S (2018) Structural
and functional dissection of differentially expressed tomato WRKY transcripts in host defense
352
L. S. Rajput et al.