Starch biosynthesis in cereal endosperms: An updated review over the last decade

Abstract

Starch is a vital energy source for living organisms and is a key raw material and additive in the food and non-food industries. Starch has received continuous attention in multiple research fields. The endosperm of cereals (e.g., rice, corn, wheat, and barley) is the most important site for the synthesis of storage starch. Around 2010, several excellent reviews summarized key progress in various fields of starch research, serving as important references for subsequent research. In the past 10 years, many achievements have been made in the study of starch synthesis and regulation in cereals. The present review provides an update on research progress in starch synthesis of cereal endosperms over the past decade, focusing on new enzymes and non-enzymatic proteins involved in starch synthesis, regulatory networks of starch synthesis, and the use of elite alleles of starch synthesis-related genes in cereal breeding programs. We also provide perspectives on future research directions that will further our understanding of cereal starch biosynthesis and regulation to support the rational design of ideal quality grain.

The Physicochemical Properties of Starch Are Affected by Wxlv in Indica Rice

“…In addition, Q11( Wx lv ) and NIL( Wx a ) starch showed similar AP1 levels at the early stage of endosperm development (5 and 10 DAF); however, from 15 DAF, Q11( Wx lv ) starch exhibited the lowest AP1 fraction, compared with the other samples. In terms of the AP2 fraction, in the three rice lines, little change was observed during endosperm development ( Figure 2 B), which was consistent with a previous study [ 28 ]. Starch from NIL( Wx b ) rice also showed a relatively higher AP2 fraction throughout endosperm development, whereas there were no significant changes in the AP2 fraction between Q11( Wx lv ) and NIL( Wx a ) before 15 DAF.…”

“…Starch accumulation is crucial for the development of the rice endosperm. It is well known that the accumulation of starch increases rapidly with the grain filling process, and this process is sensitive to the environmental temperature [ 28 , 29 ]. However, only a few studies have focused on the accumulation of various components of starch during rice grain filling [ 30 ].…”

Transcriptional Regulation of Quinoa Seed Quality: Identification of Novel Candidate Genetic Markers for Increased Protein Content

“…Cereal endosperm is a major source of storage starch ( Huang et al, 2021 ) and starch is also the major storage compound in quinoa seeds where it is mostly stored in the perisperm. Large changes in the expression of genes that govern starch synthesis in seeds can therefore be expected to have an impact on seed quality.…”

OsNAC129 Regulates Seed Development and Plant Growth and Participates in the Brassinosteroid Signaling Pathway

“…After decades of investigation, the key enzymes including ADP-glucose pyrophosphorylase (AGPase), granule bound starch synthases (GBSSs), soluble starch synthases (SSs), starch branching enzymes (SBEs), debranching enzymes (DBEs), and starch phosphorylases (PHOs) involved in this pathway have been fully characterized and are well reviewed in the literature ( Jeon et al, 2010 ; Zhu et al, 2020 ; Huang et al, 2021 ). Among these enzymes, AGPase is an allosterically rate-limited enzyme responsible for synthesis of the starch substrate ADP-glucose (ADPG); GBSSs, especially GBSSI, are the only enzymes responsible for amylose synthesis; SSs, SBEs, and DBEs are cooperatively responsible for the synthesis of amylopectin; PHOs are thought to function in starch initiator synthesis ( Jeon et al, 2010 ; Zhu et al, 2020 ; Huang et al, 2021 ). When these synthases involved in starch synthesis are dysfunctional, seed development and the filling process are disturbed, leading to abnormal seed phenotypes.…”