YNL194C encodes a plasma membrane protein that localizes to stable cortical domains in yeast. These domains are distinct from actin patches, euchromatin, or other membrane compartments, and their formation depends on interactions with the cell wall . The YNL194C antibody specifically binds to epitopes within this protein, enabling its detection in fluorescence microscopy, immunoprecipitation, and Western blotting .
YNL194C antibodies have been utilized in diverse experimental setups:
Epifluorescence/TIRF Microscopy: Anti-c-Myc or anti-HA epitope tags fused to YNL194C enabled visualization of its cortical patches .
Co-Localization: Demonstrated overlap with Pil1 in membrane furrows, suggesting a role in stabilizing BAR domain-induced membrane curvature .
Gene Deletion: ynl194cΔ mutants exhibited reduced sporulation efficiency and altered membrane dynamics .
Protein-Protein Interactions: Co-immunoprecipitation with tagged YNL194C identified associations with NUM1 and other cortical proteins .
Antibody Validation: Specificity confirmed via Western blotting in ynl194cΔ knockout strains .
Epitope Tags: Common tags include 9xMyc or HA, introduced via homologous recombination for controlled expression .
Cross-Reactivity: No cross-reactivity reported with other Sur7p family members (e.g., Sur7p, Ydl222p) .
KEGG: sce:YNL194C
STRING: 4932.YNL194C
YNL194C is one of three related integral membrane proteins in Saccharomyces cerevisiae that form a family including Sur7p, Ynl194p, and Ydl222p. These proteins define novel cortical patch structures in the yeast plasma membrane. YNL194C is particularly significant because it shows differential expression compared to its family members, being specifically induced during the shift to anaerobic metabolism, carbon starvation, and osmotic shock conditions . This unique expression pattern makes YNL194C a valuable marker for studying cellular responses to environmental stresses in yeast.
YNL194C shares 27-34% sequence identity and 42-49% similarity with Sur7p and Ydl222p. All three proteins are predicted to contain 301-309 residues with three transmembrane helices, but they show different patterns of conservation: the extracellular portions are more highly conserved (33.6% identical residues across all three proteins) compared to the intracellular and transmembrane portions (5.2% and 16% identity, respectively) .
Functionally, while all three proteins localize to cortical patches, their expression is differentially regulated: YNL194C expression increases during anaerobic shifts, carbon starvation, and osmotic shock, whereas SUR7 expression peaks in late G2/M phase, and YDL222 is induced during pseudohyphal growth or osmotic shock .
For generating specific antibodies against YNL194C, researchers should consider the following evidence-based approaches:
Peptide selection: Target the extracellular domain of YNL194C which comprises approximately the N-terminal third of the protein. This region shows higher sequence divergence from Sur7p and Ydl222p, making it ideal for generating specific antibodies.
Recombinant protein production: Express the extracellular domain as a fusion protein to enhance immunogenicity while avoiding the hydrophobic transmembrane domains that can complicate expression and purification.
Validation strategy: Cross-validate antibody specificity using YNL194C deletion strains (ynl194cΔ::HIS3) as negative controls, as these have been successfully generated and characterized .
A comprehensive validation approach should include:
Western blotting: Compare wild-type strains with ynl194cΔ mutants (such as YJC2044) to confirm absence of signal in the deletion strain.
Immunofluorescence microscopy: Compare localization patterns with known YNL194C-GFP or YNL194C-9myc fusion proteins (such as those in strains YJC2032 or YJC2080) .
Cross-reactivity testing: Test against strains with individual and combined deletions of SUR7, YDL222, and YNL194C to ensure specificity within this protein family.
Tagged protein controls: Use strains containing tagged versions like YNL194C-9myc (YJC2080) as positive controls where the protein can be detected with anti-myc antibodies in parallel .
Based on current research, an optimal experimental design would include:
Treatment conditions: Include anaerobic shift, carbon starvation, and osmotic shock treatments, as these are known to induce YNL194C expression .
Time course analysis: Monitor YNL194C levels at multiple timepoints (0, 15, 30, 60, 120, 240 minutes) after stress induction.
Controls: Include Sur7p and Ydl222p detection in parallel to compare differential regulation.
Variables to control: Maintain consistent cell density, growth phase, and media composition across experiments to minimize variation.
Quantification method: Use quantitative western blotting or flow cytometry with YNL194C antibodies, calibrated against a standard curve of purified protein.
This design follows the principles of good experimental practice outlined in source , including careful consideration of variables, appropriate controls, and measurement methods.
For investigating cortical patch dynamics:
Live cell imaging: Combine immunofluorescence using YNL194C antibodies with time-lapse microscopy to track patch formation and dissolution.
Co-localization studies: Use dual-labeling approaches to examine relationships between YNL194C patches and other cortical structures.
Cell wall integrity analysis: Since Sur7p family patches require cell wall-dependent extracellular interactions for localization , perform parallel studies with and without cell wall digestion to understand the dependence of YNL194C patch formation on cell wall integrity.
Quantitative image analysis: Measure patch number, size, intensity, and distribution under different stress conditions to correlate patch characteristics with cellular responses.
To resolve contradictory data:
Standardized induction protocols: Develop precise protocols for each stress condition, controlling for factors like severity and duration.
Strain background effects: Test multiple strain backgrounds to identify genetic modifiers of YNL194C expression and localization.
Single-cell analysis: Use techniques like microfluidics combined with live-cell imaging to analyze cell-to-cell variation in YNL194C patch formation.
Multi-omics approach: Combine antibody-based detection with transcriptomics and proteomics to identify potential post-transcriptional or post-translational regulation affecting YNL194C abundance and localization.
Comparative analysis: Create a standardized comparison table that accounts for different experimental conditions:
Several factors can contribute to antibody performance issues:
Epitope accessibility: The cortical patch localization of YNL194C may limit antibody access in fixed cells. Consider optimizing fixation and permeabilization protocols.
Expression levels: YNL194C is differentially expressed and may be present at low levels under standard growth conditions. Induce expression using appropriate stress conditions before antibody detection.
Strain-specific variations: Minor sequence variations in different laboratory strains could affect antibody binding. Verify the sequence of YNL194C in your specific strain.
Post-translational modifications: Potential modifications might mask epitopes. Consider using multiple antibodies targeting different regions of the protein.
Detection method sensitivity: For low abundance proteins, enhance detection using signal amplification methods or more sensitive detection systems.
For precise discrimination between family members:
Epitope mapping: Use antibodies raised against the least conserved regions of each protein. The extracellular portions have 33.6% identity across all three proteins, while intracellular portions have only 5.2% identity .
Deletion strain controls: Include single, double, and triple deletion strains (such as YJC2122 with sur7Δ::HIS3 ydl222cΔ::HIS3 ynl194cΔ::HIS3) to validate specificity.
Expression conditions: Leverage differential expression patterns - YNL194C is induced during anaerobic metabolism shifts and carbon starvation, SUR7 in late G2/M phase, and YDL222 during pseudohyphal growth .
Sequential immunoprecipitation: Perform sequential immunoprecipitations using antibodies specific to each family member to separate and quantify individual proteins.
The following statistical approaches are recommended:
For patch quantification: Use mixed-effects models to account for both fixed effects (treatment conditions) and random effects (cell-to-cell variability).
For co-localization analysis: Calculate Pearson's or Manders' correlation coefficients between YNL194C and other markers.
For time-course experiments: Apply repeated measures ANOVA or longitudinal data analysis methods.
For comparison across strains: Use nested ANOVA designs to account for biological and technical replicates.
For image analysis: Implement machine learning approaches for unbiased quantification of patch characteristics (size, intensity, distribution).
For comprehensive integration:
Correlative analysis: Correlate YNL194C protein levels or localization patterns with phenotypic outcomes such as sporulation efficiency, which is reduced in ynl194Δ mutants .
Genetic interaction mapping: Compare YNL194C expression and localization across genetic backgrounds with different combinations of deletions in related pathways.
Structure-function correlations: Relate antibody-detected protein levels to functional assays such as stress resistance.
Multi-dimensional data integration: Create integrated visualizations combining protein localization, expression levels, and phenotypic measurements across conditions.
Given that YNL194C is part of a family implicated in stress responses:
Oxidative stress induction: Compare YNL194C patch dynamics before and after hydrogen peroxide treatment, using concentrations similar to those in oxidative stress tolerance studies .
Co-localization with stress response machinery: Examine whether YNL194C patches co-localize with proteasomal subunits that are upregulated during adaptation to oxidative stress .
Genetic background effects: Use antibodies to compare YNL194C localization between wild-type strains and strains with exceptionally high tolerance to hydrogen peroxide, such as those with Chromosome IV duplications .
Temporal dynamics: Track the timing of YNL194C patch formation relative to the expression of known oxidative stress response genes like TSA1 and TSA2 .
Emerging technological approaches include:
Super-resolution microscopy: Apply techniques like STORM or PALM with YNL194C antibodies to resolve the fine structure of cortical patches beyond the diffraction limit.
Proximity labeling: Use YNL194C antibodies in conjunction with BioID or APEX2 proximity labeling to identify proteins in the immediate vicinity of YNL194C patches.
Single-cell proteomics: Combine YNL194C immunolabeling with single-cell mass spectrometry to correlate patch formation with global proteome changes at the individual cell level.
In situ structural analysis: Apply emerging techniques like cryo-electron tomography with immunogold labeling to visualize YNL194C in its native cellular context.