Mutant-Based Reverse Genetics for Functional Genomics of Non-model Crops

Abstract

In the past decade, innovations in high-throughput sequencing (next-generation sequencing) technologies have accelerated whole-genome sequencing of various non-model crop species. Taking advantage of huge polymorphic sequence data provided by the results of whole-genome sequencing, we can easily develop novel molecular markers. It may boost the use of forward genetics approach to isolating the corresponding genes for QTLs in non-model crops. Furthermore, this forward genetics approach is a steady and robust method but it is still difficult to increase its throughput. The sequenced genes have been annotated on the basis of sequence similarity; however, the functions of most genes (and the resulting phenotypes) are still obscure. Although we can easily obtain multiple crop genomic sequences from public databases, it is necessary to increase the throughput of functional genomics. Reverse genetics, which uses mutants or transgenic lines for the genes of interest, is an attractive approach to determine gene function. Mutant-based reverse genetics has several advantages over transgene-based reverse genetics: (a) its higher throughput, (b) the absence of restrictions for growing non-transgenic mutants in the field and (c) the possibility to use the mutants directly for traditional cross-breeding programs as valuable genetic resources of non-model crops. This chapter describes recent advances in functional genomics research on non-model crops, with a focus on mutant-based reverse genetics approaches.