Resistant starch: biosynthesis, regulatory pathways, and engineering via CRISPR system

Genetic Engineering of Starch Biosynthesis in Maize Seeds for Efficient Enzymatic Digestion of Starch during Bioethanol Production

“…Starch synthesis of cereal crops is the primary determinant of grain filling [ 92 ]. The current knowledge on regulation of starch accumulation in the endosperms is mainly obtained using model cereal crops, such as rice, maize and wheat [ 9 , 18 , 88 , 92 , 93 , 94 , 95 , 96 ]. Identifying the key proteins/enzymes involved in starch synthesis during maize seed development is critical for understanding the molecular mechanism of starch synthesis and improving starch properties for efficient bioethanol production.…”

“…A combinatorial approach through genomics, proteomics, and other associated-omics branches of biotechnology is proving to be an effective way for accelerating genes or enzymes discovery and the crop improvement programs. Compared with traditional plant breeding methods (e.g., cross-breeding, mutation breeding), genetic engineering techniques can precisely target DNA sequence to obtain desired agronomic traits (e.g., high quality, high yield and stress resistance) of plants [ 18 , 19 , 20 , 21 , 22 ]. Especially, CRISPR (clustered regularly inter-spaced short palindromic repeats)-Cas (CRISPR associated), as one of the most advanced technologies for engineering crop genomes, has been rapidly expanding and applied to major cereals such as rice, wheat and maize in recent years [ 22 ].…”

“…Among six maize hybrids investigated in Serbia, the hybrid ZP 434 was found to be most suitable for bioethanol production, due to its higher level of soft endosperm and more easily degradation by starch-hydrolyzing enzymes [ 17 ]. Genetic engineering technology can accurately operate the target DNA sequences to obtain plants with ideal agronomic traits, but most efforts aimed to obtain crops with high yield, high quality and stress resistance [ 18 , 19 , 20 , 21 , 22 ]. Thus far, only a few maize lines with different composition, structure and properties of starch were obtained by genetic engineering techniques.…”