About this Research Topic
Phytopathogenic bacteria of the Xanthomonas genus cause severe diseases on hundreds host plants, including economically important crops, such as rice, wheat, cassava, banana, mango, tomato, citrus, cabbage, pepper, bean and cotton. Diseases occurring in nature comprise black rot, leaf/fruit spot, canker, wilt, leaf blight and streak. These bacteria are present worldwide where some phytopathogenic strains are emergent or re-emergent and, consequently, dramatically impact agriculture, economy and food safety.
Xanthomonas bacteria provide excellent models for genomic studies and hundreds of Xanthomonas genome sequences have been obtained since 2002 and many other are underway (www.xanthomonas.org/genomes.html). Comparative genomics between and/or within bacterial species and/or pathovars will be of a great help to decipher commonalities and particularities that underly host range definition.
Most of the Xanthomonas possesses a type III secretion system (T3SS) that is required for injection of various effectors inside plant cells, thus contributing to pathogenicity. Transcription Activator-Like (tal) genes, encode bacterial transcription factors which are injected through the T3SS by many Xanthomonas to promote pathogenicity. Some Ralstonia, Bulkholderia and marine bacteria also express TAL-like proteins which function and mode of action is starting to be deciphered. TALs are addressed to the plant nucleus where they activate plant gene expression by direct binding to the corresponding promoter sequences. Targeted genes essentially act as susceptibility genes. A few years after the cracking of the code allowing the TAL/Host promoter sequence recognition, combined to the ever-growing availability of plant genomes, many efforts have been done to identify TAL targets. These data collected for many Xanthomonas/host pathosystems will assuredly help breeders to breed resistance resistant in important crops.
In this Research Topic we aim to collect manuscripts covering the current knowledge of Xanthomonas genomics and effectomics, with a special focus on TAL effector biology. Specifically, we encourage the submission of manuscripts (Original Research, Hypothesis & Theory, Methods, Reviews, Mini Reviews, Perspective and Opinion) covering the following topics:
1. Manuscripts reporting genome sequencing of Xanthomonas strains.
2. Manuscripts describing functional and comparative genomics in Xanthomonas species/pathovars.
3. Manuscripts describing functional studies on Xanthomonas type III effectors.
3. Manuscripts describing discovery, evolution, bio-informatics and functional genomics of TAL effectors and their targets in plant genomes, as well as for TAL-like in non-Xanthomonas bacteria.
4. Manuscripts describing applications of TAL effector research for resistance breeding in crops.
We anticipate that this Research Topic will be of importance for plant pathologists and breeders.
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.