Evolutionary analysis of plant jacalin-related lectins (JRLs) family and expression of rice JRLs in response to Magnaporthe oryzae

Abstract

Jacalin-related lectins (JRLs) are widely distributed carbohydrate-binding proteins in the plant kingdom, which play key roles in development and pathogen defense. In this study, we profiled evolutionary trajectory of JRLs family in 30 plant species and identified domain diversification and recombination leading to different responsive patterns of JRLs in rice during defense against rice blast. All of 30 plant species analyzed in our study have two types of JRLs by containing either a single jacalin or repeated jacalin domains, while chimeric jacalins exist in more than half of the species, especially in the Poaceae family. Moreover, Poaceae species have evolved two types of unique chimeric JRLs by fusing the jacalin domain(s) with Dirigent or NB_ARC domain, some of which positively regulate plant immunity. Seven Poaceae-specific JRLs are found in the rice genome. We further found expression of rice JRLs, including four Poaceae-specific JRLs, are induced by Magnaporthe oryzae infections at either early or late infection stages. Overall, the results present the evolutionary trajectory of JRLs in plant and highlight essential roles of Poaceae specific JRLs against pathogen attacks in rice.

Lectin Sequence Distribution in QTLs from Rice (Oryza sativa) Suggest a Role in Morphological Traits and Stress Responses

“…The presence of lectin sequences in QTLs attributed to resistance/tolerance was analyzed in detail since lectins have been associated with plant defense and the perception of pathogens or abiotic stress in multiple publications [17,19,27]. Many rice lectin sequences are located in QTL regions annotated as being responsible for resistance/tolerance, the percentage of lectin sequences in QTLs related to abiotic stresses (ranging from 40% to 100% for different lectin families) being markedly higher than those attributed to biotic stresses (10–43% for different lectin families, see Supplementary Information, Table S5).…”

“…NB-ARC is a motif spread through pro- and eukaryotes and is involved in plant defense as a part of the R (resistance) genes [19]. The combination of a Jacalin domain and a dirigent domain is unique for monocots [27,28], and all proteins with this domain architecture separate in clade 6 of the tree. Clade 4 groups mainly proteins consisting of an NB-ARC domain linked to 3 Jacalin domains as well as proteins composed of a protein kinase domain and 1 to 3 Jacalin domains.…”

Reckless driving: Improved phosphorous availability is a most likely important driver and species killer in angiosperm evolution

“…Such duplications are generally followed by fast removal of duplicated genes not finding relevant functions in double copies or as new genes and the plant revert to the diploid state although traces of the gene duplication event is left in the genome (Leitch, I. J. & Bennett, M. D., 2004; Šmarda et al, 2013; Han et al, 2018). There is also no correlation between size of genome and phylogenetic history in severely nutrient limited karst plants (Kang, Wang & Huang, 2015) even if phosphorous limitations after whole genome expansion events can restrain plants with large genomes and limit their competitiveness (Šmarda et al, 2013).…”

“…Even ploidies changes followed by changes in gene functions of multiplied genes followed by sexual recombination could result in better fitness and ultimately the formation of a new species (Leitch, I. J. & Bennett, M. D., 2004; Šmarda et al, 2013; Han et al, 2018). Thus, the punishment for a phosphorous drain by an increase in genome size should be smaller and the slope of the decrease in n-size less steep for even number ploidies than for odd number ploidies.…”

A Magnaporthe Chitinase Interacts with a Rice Jacalin-Related Lectin to Promote Host Colonization

“…The rice JRL OsJAC1 confers resistance against pathogens by its dirigent and jacalin domain (Weidenbach et al, 2016). Wheat (Triticum aestivum) TaJA1 (an OsJAC1 ortholog) and TaJRLL1 (jacalin-related lectin-like) are both induced by pathogen infection and lead to resistance against fungal diseases (Xiang et al, 2011;Weidenbach et al, 2016;Han et al, 2018), demonstrating the importance of JRLs in plant immunity. However, it is unclear how JRLs interact with fungal pathogens.…”