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Background and Objectives: Maize is a major ingredient of animal feed. However, its nutritional quality is poor due to the deficiency of essential amino acid methionine. The animal feed, prepared as a corn–legume mixture to balance the nutritional quality, remains deficient in methionine. Therefore, the bio‐fortification of maize for methionine is the best option to make nutritionally balanced animal and poultry feed. The present study was designed to evaluate the profile of zeins and the expression profile of methionine‐associated target genes in high‐ and low‐methionine maize. Findings: Results of sodium dodecyl sulfate‐polyacrylamide gel electrophoresis revealed that the 10‐kDa zein was accumulated during kernel development, and its accumulation was higher in high methionine lines. Gene expression analysis through real‐time polymerase chain reaction revealed that higher expression of 10‐ and 18‐kDa zeins is associated with higher methionine accumulation. Conclusions: The above results indicate that 10‐ and 18‐kDa genes are the potential targets for the methionine bio‐fortification in maize, which is required for animal and poultry feed. Significance and Novelty: The present study suggests that 10‐ and 18‐kDa genes are the major source of methionine, and the regulation of these genes is crucial to enhancing the methionine content in maize. The results indicate that these genes are potential targets for genetic engineering in maize to enhance methionine accumulation. [ABSTRACT FROM AUTHOR]

Background and Objectives: Zein proteins of maize endosperm are nutritionally poor, but important for vitreous kernel texture. The Opaque‐2 mutation enhances the protein quality but downregulates zein expression, distorting the kernel texture. Quality protein maize (QPM) is nutritionally improved, hard endosperm maize developed by introgression of endosperm modifiers under an opaque‐2 background. The present study aims to analyze the variability in zein expression patterns in normal, opaque‐2, and QPM lines through sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and two‐dimensional gel electrophoresis analyses. Findings: Results revealed that the total number of zein isoforms is almost similar in opaque‐2, normal, and QPM lines. Overall, in this study, it is concluded that the opaque‐2 mutation specifically affects the expression of high‐molecular‐weight zeins, which are being counterbalanced by the expression of low‐molecular‐weight zein isoforms and nonzein proteins. Conclusion: Genomic data retrieval studies revealed the possible presence of multiple 27 kDa isoforms with varied isoelectric points (pI), which is a subject for further investigation. The differential expression of 15 kDa zein in QPM emerged as a novel player in endosperm modification. Significance and Novelty: The present study provides insight into the diversified expression of zeins in different maize types. The variable isoform expression has the potential to generate stable QPM lines by targeting effective isoforms, ensuring endosperm modification without hampering the nutritional quality. [ABSTRACT FROM AUTHOR]

In recent years, a tremendous amount of inquisitiveness among scientists in the clustered regularly interspaced short palindrome repeats (CRISPR)–CRISPR‐associated proteins (Cas) has led to many studies to delineate their exact role in prokaryotes. CRISPR–Cas is an adaptive immune system that protects prokaryotes from phages and mobile genetic elements. It incorporates small DNA fragment of the invader in the CRISPR‐array and protects the host from future invasion by them. In a few instances, the CRISPR‐array also incorporates self‐targeting spacers, most likely by accident or leaky incorporation. A significant number of spacers are found to match with the host genes across the species; however, self‐targeting spacers have not been investigated in detail in most of the organisms. The presence of self‐targeting spacers in the CRISPR‐array led to speculation that the CRISPR–Cas system has a lot more to offer than just being the conventional adaptive immune system. It has been implicated in gene regulation and autoimmunity more or less equally. In this review, an attempt has been made to understand self‐targeting spacers in the context of gene regulation, autoimmunity, and its avoidance strategies. [ABSTRACT FROM AUTHOR]