PAH1 Antibody

Target Protein: PAH1 Phosphatidate Phosphatase

PAH1 is a yeast enzyme critical for lipid homeostasis, balancing TAG storage and membrane phospholipid synthesis. Its activity is regulated by phosphorylation/dephosphorylation cycles and interactions with regulatory complexes like Nem1-Spo7 .

Applications of PAH1 Antibody in Research

PAH1 antibodies are primarily used to study enzyme localization, phosphorylation states, and mutant phenotypes.

Common Techniques

• Western Blot (WB): Detects PAH1 expression levels and phosphorylation status (e.g., slower electrophoretic mobility indicates dephosphorylation) .

• Immunoblot Analysis: Quantifies membrane vs. cytosolic PAH1 fractions to assess regulatory mechanisms .

• Enzyme Activity Assays: Correlates PAH1 protein levels with phosphatidate phosphatase (PAP) activity .

Key Findings Using PAH1 Antibodies

• Mutation Analysis: The pah1Δ mutant exhibits elevated phosphatidylserine synthase (PSS) activity and Cho1 protein levels, linked to disrupted lipid regulation .

• Phosphorylation Effects: Phosphorylation at Ser-748/Ser-773 by Hsl1 reduces PAP catalytic efficiency by 5-fold .

• Domain Function: Deletion of the regulatory RP domain reduces phosphorylation (by 57%), increases membrane association, and destabilizes PAH1 .

Phosphorylation-Dependent Regulation

• PAH1 phosphorylation (e.g., by Hsl1 at Ser-748/Ser-773) reduces PAP activity and stabilizes the cytosolic form .

• Dephosphorylation by Nem1-Spo7 enables membrane binding and TAG synthesis .

Mutant Phenotypes

• Pah1-W637A: Increased membrane association (2.9-fold vs. wild type) and elevated PAP activity (4.4-fold in membranes) .

• ΔRP Mutant: Reduced phosphorylation enhances membrane localization but decreases protein stability .