Agronomy and Horticulture Department
ORCID IDs
0000-0002-3306-7637
0000-0001-5952-2266
0000-0002-1827-8137
0000-0003-3158-1963
Date of this Version
2018
Citation
Genomics Proteomics Bioinformatics 16 (2018) 439–450
Abstract
Despite the large number of genomic and transcriptomic resources in maize, there is still much to learn about the function of genes in developmental and biochemical processes. Some maize mutants that were generated by gamma-irradiation showed clear segregation for the kernel phenotypes in B73 X Mo17 F2 ears. To better understand the functional genomics of kernel development, we developed a mapping and gene identification pipeline, bulked segregant exome sequencing (BSEx-seq), to map mutants with kernel phenotypes including opaque endosperm and reduced kernel size. BSEx-seq generates and compares the sequence of the exon fraction from mutant and normal plant F2 DNA pools. The comparison can derive mapping peaks, identify deletions within the mapping peak, and suggest candidate genes within the deleted regions. We then used the public kernel-specific expression data to narrow down the list of candidate genes/mutations and identified deletions ranging from several kb to more than 1 Mb. A full deletion allele of the Opaque-2 gene was identified in mutant 531, which occurs within a ~200-kb deletion. Opaque mutant 1486 has a 6248-bp deletion in the mapping interval containing two candidate genes encoding RNA-directed DNA methylation 4 (RdDM4) and AMP-binding protein, respectively. This study demonstrates the efficiency and cost-effectiveness of BSEx-seq for causal mutation mapping and candidate gene selection, providing a new option in mapping-by-sequencing for maize functional genomics studies.
Included in
Agricultural Science Commons, Agriculture Commons, Agronomy and Crop Sciences Commons, Botany Commons, Horticulture Commons, Other Plant Sciences Commons, Plant Biology Commons
Comments
© 2019 The Authors.
Open access
https://doi.org/10.1016/j.gpb.2018.02.003