PDIL1-1 Antibody

Definition and Biological Role

PDIL1-1 is a member of the protein disulfide isomerase (PDI) family, which facilitates disulfide bond formation and protein folding in the endoplasmic reticulum (ER). In rice (Oryza sativa), PDIL1-1 specifically regulates the oxidative folding of vacuole-targeted storage proteins such as proglutelins and α-globulin, ensuring proper seed development and nutrient storage . Loss of PDIL1-1 disrupts starch granule formation, increases reactive oxygen species (ROS)-related proteins, and causes irregular protein bodies, leading to chalky endosperm phenotypes .

Applications of PDIL1-1 Antibody

The PDIL1-1 antibody has been utilized in multiple experimental contexts:

Key Applications

• Western Blotting: Detects PDIL1-1 expression in rice seeds during developmental stages (5–50 days after flowering) .

• Mutant Analysis: Identifies PDIL1-1Δ knock-out mutants, which exhibit reduced protein content, elevated free sugars, and thickened aleurone layers .

• Protein Interaction Studies: Confirms PDIL1-1’s interaction with cysteine protease OsCP1, suggesting a role in inhibiting premature programmed cell death (PCD) during seed maturation .

Example Protocol (Western Blot)

Functional Insights

• Seed Phenotype: PDIL1-1Δ mutants show a 20% reduction in total seed protein and a 35% increase in free sugars compared to wild-type seeds .

• Proteomic Alterations: Loss of PDIL1-1 causes accumulation of glucose/starch metabolism enzymes (e.g., α-amylase) and ROS scavengers (e.g., peroxiredoxin) .

• Compensatory Mechanisms: PDIL1-1 deficiency upregulates related PDIs (e.g., PDIL2-3), which localize cysteine-rich prolamins but cannot rescue proglutelin misfolding .

Comparative Roles of PDIL Proteins

Technical Validation

• Specificity: The anti-PDIL1-1 antibody detects a single band at ~57 kDa in rice seed extracts, with no cross-reactivity to other PDIL isoforms .

• Developmental Regulation: PDIL1-1 expression peaks at 20–30 days after flowering, coinciding with active storage protein synthesis .