National Agri-Food Biotechnology Institute

The molecular details of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) and their functional significance in combating environmental stress in crop species remain inadequately elucidated. Tomato (Solanum lycopersicum) is an important crop, sensitive to temperature, and serves as a model crop plant for studying these pathways. To establish a tomato UPR transcriptome profile, we performed RNA sequencing (RNA-seq) analysis of tomato seedlings under tunicamycin (Tm)-induced ER stress. The 339 differentially expressed genes encompassed traditional ER stress markers, ER-associated degradation elements, transcription factors, and novel candidate genes. Our functional analysis of key UPR genes, viz., SlIRE1A, SlIRE1B, SlbZIP60, and SlbZIP28, using Virus-Induced Gene Silencing (VIGS) revealed differential requirements for SlIRE1A and SlIRE1B in the Tm-induced upregulation of downstream genes. Additionally, we found that the expression of most of the downstream genes we analyzed was equally dependent on both the IRE1 and bZIP28 pathways. The expression analysis of several of these genes under environmental stress conditions indicated that their expression patterns did not align with those observed during ER stress. Furthermore, our analysis of VIGS plants subjected to heat stress revealed that the regulation of reactive oxygen species (ROS) levels in tomato depends on the IRE1-bZIP60 pathway. Overall, this study provides a comprehensive analysis of UPR pathways in tomato and offers essential molecular insights for developing resilient tomato cultivars that can withstand adverse environmental conditions.

Abstract C 4 photosynthesis evolved through adaptive changes in key metabolic enzymes that enhance carbon fixation efficiency, yet transferring such traits into C 3 crops has met limited success. Using precision prime editing, we introduced an evolutionarily conserved single amino acid substitution (Arg→Gly) into phosphoenolpyruvate carboxylase (PEPC) in rice. Edited plants exhibited enhanced PEPC activity in the presence of the feedback inhibitor malate, increased chlorophyll content, elevated photosynthetic rates under ambient CO 2 , and increased seed size and weight. Remarkably, seeds from the edited lines showed simultaneous enrichment of zinc (Zn), iron (Fe), and protein, hereafter referred to as ZiP rice. This work demonstrates that a single, evolutionarily guided residue change can reprogram core carbon metabolism in a C 3 crop, enabling concurrent improvements in photosynthesis and grain nutritional quality.

Multiple studies have reported genetic evidence of crop-to-wild introgression in phenotypically wild accessions of wild barley (Hordeum vulgare ssp. spontaneum). We examined 318 Wild Barley Diversity Collection (WBDC) accessions for evidence of introgression from domesticated barley. Using SNP genotyping data, we performed local ancestry inference between the WBDC accessions and domesticated barley to identify genomic regions with evidence of introgression. Using the genomic intervals for well-characterised genes involved in domestication and improvement, we examined the evidence for introgression at genomic regions potentially important for maintaining a wild phenotype. Our analysis revealed that nearly 16% (48 of 318) of WBDC accessions showed evidence of introgression from domesticated barley, with up to 16.6% of the genome introgressed. All accessions identified as introgressed based on domestication-related phenotypes show clear genetic evidence of introgression. The size of runs of identity by state and local ancestry inference suggests that most introgression did not occur recently. This study suggests a long history of genetic exchange between wild and domesticated barley, highlighting the potential for introgression to influence the genetic makeup and future adaptation of wild populations, with implications for plant conservation strategies.

Transforming food waste into food safety: preparation and detailed characterization of an antioxidant, sustainable, and preservative-active food packaging material derived from onion peel agro-waste.

Sheep milk is a rich source of proteins with potential to generate bioactive peptides through microbial fermentation. However, limited studies have focused on the Panchali sheep breed of India and the multifunctional health properties of its fermented products. This study investigated the generation of bioactive peptides with antidiabetic, antioxidative, and anti-inflammatory properties through the fermentation of sheep milk using a potent LAB, Limosilactobacillus fermentum (KGL4, MTCC 25515), in combination with the yeast strain Saccharomyces cerevisiae (WBS2A, MG101828). Optimal bioactivity was observed after 48 h of fermentation at 30 °C, with antioxidant activity reaching 40.08%, α-amylase inhibition at 72.48%, and α-glucosidase inhibition at 75.96%. Proteolytic activity was assessed at varying inoculum concentrations (1.5, 2 and 2.5%) and incubation time (0, 12, 24, 36 and 48 h), with the highest activity (6.74 mg/mL) observed at a 2.5% inoculum after 48 h. Additionally, fermented milk effectively lowered the production of pro-inflammatory cytotoxins and ROS in LPS-induced RAW 267.4 macrophage cells, indicating its anti-inflammatory properties. Protein profiling through SDS-PAGE revealed bands between 15 and 70 kDa, while 2D electrophoresis identified 39 distinct protein spots associated with peptide production. Reverse-phase HPLC of ultrafiltered water-soluble extracts (WSEs) was used to separate peptide fractions, and identified sequences were assessed through comparison with BIOPEP database to confirm antidiabetic and antioxidative activities. The most potent selected peptide showed strong binding affinity and stable interaction within the active pockets of human α-amylase and α-glucosidase, as well as high HADDOCK and HPEPDOCK scores in molecular docking analyses. These findings indicate that fermented sheep milk is a promising source of multifunctional bioactive peptides with potential applications in functional foods targeting diabetes and inflammation. Further in vivo studies are warranted to validate physiological relevance, bioavailability, and health benefits.