Identification of Immune Related LRR-Containing Genes in Maize (Zea maysL.) by Genome-Wide Sequence Analysis

Abstract

A large number of immune receptors consist of nucleotide binding site-leucine rich repeat (NBS-LRR) proteins and leucine rich repeat-receptor-like kinases (LRR-RLK) that play a crucial role in plant disease resistance. Although many NBS-LRR genes have been previously identified in Zea mays, there are no reports on identifying NBS-LRR genes encoded in the N-terminal Toll/interleukin-1 receptor (TIR) motif and identifying genome-wide LRR-RLK genes. In the present study, 151 NBS-LRR genes and 226 LRR-RLK genes were identified after performing bioinformatics analysis of the entire maize genome. Of these identified genes, 64 NBS-LRR genes and four TIR-NBS-LRR genes were identified for the first time. The NBS-LRR genes are unevenly distributed on each chromosome with gene clusters located at the distal end of each chromosome, while LRR-RLK genes have a random chromosomal distribution with more paired genes. Additionally, six LRR-RLK/RLPs including FLS2, PSY1R, PSKR1, BIR1, SERK3, and Cf5 were characterized in Zea mays for the first time. Their predicted amino acid sequences have similar protein structures with their respective homologues in other plants, indicating that these maize LRR-RLK/RLPs have the same functions as their homologues act as immune receptors. The identified gene sequences would assist in the study of their functions in maize.

Structural evolution drives diversification of the large LRR‐RLK gene family

“…They are also used extensively in defense against pathogens (Diévart & Clark, ; Huffaker & Ryan, ; Sakamoto et al , ; Peng & Kaloshian, ). Some impact agronomically important developmental processes and can impact yield, making them appealing targets for crop improvement (Diévart & Clark, ; Song et al , ; Je et al , ; Rodríguez‐Leal et al , ; Lemmon et al , ).…”

Comparative Histological and Transcriptional Analysis of Maize Kernels Infected with Aspergillus flavus and Fusarium verticillioides

“…In plants, both coiled-coil nucleotide-binding site leucine-rich repeat (CC-NBS-LRR) and leucine-rich repeat receptor-like kinase (LRR-RLK) receptors are R-like proteins important in the resistance response to pathogens. Of the 378 R-like genes predicted in the maize genome ( Ling et al, 2010 ; Song et al, 2015 ), 40 of 151 predicted CC-NBS-LRR genes were differentially expressed during infection by A. flavus and/or F. verticillioides . Of the 227 predicted LRR-RLK genes in maize, 36 were differentially expressed during one or more time points.…”

“…Then we used the MaizeSequence database to obtain gene annotation ( Schnable et al, 2009 ). For the genes without annotation in MaizeSequence database, we combined a few databases, including MaizeGDB, ProFITS, GRASSIUS, CoGePedia, Maize Protein Atlas databases ( Lawrence et al, 2004 ; Lyons and Freeling, 2008 ; Yilmaz et al, 2009 ; Ling et al, 2010 ; Castellana et al, 2013 ) and the R-like gene database published by Song et al (2015) . Differentially expressed maize genes were also placed into biosynthetic and regulatory pathways using the MaizeCyc database and the bioinformatics software Biocyc ( Caspi et al, 2012 ).…”

Characterization, Identification and Expression Profiling of Genome-Wide R-Genes in Melon and Their Putative Roles in Bacterial Fruit Blotch Resistance

“…These domains are involved in pathogen recognition, signaling, and plant innate immunity responses [26,27,29,[31][32][33][34][35]. R-genes have been identified in the genomes of plant species including watermelon [36], cucumber [37], rice [38,39], Chinese cabbage [40], maize [41], wheat [42], Arabidopsis thaliana [43], and apple [44].…”