POF1 Antibody

What is POF1B and what cellular functions does it perform?

POF1B (premature ovarian failure, 1B) is a protein that plays a critical role in the organization of epithelial monolayers through regulation of the actin cytoskeleton. It has been identified as a candidate gene for premature ovarian failure (POF) and is predominantly expressed in polarized epithelial tissues .

In contrast, the yeast POF1 (promoter of filamentation) protein is involved in protein quality control pathways and demonstrates ATPase activity. Research indicates that yeast POF1p shows an ATPase-specific activity of approximately 5 nmol of released phosphate per hour per μM enzyme, comparable to the ATPase activity of ERAD-associated proteins like Kar2p .

What is the recommended starting dilution range for POF1B antibody applications?

For research applications, POF1B antibody (such as catalog 11398-1-AP) requires different dilutions depending on the experimental method:

It is strongly recommended that researchers titrate the antibody in their specific experimental system to determine optimal conditions, as optimal dilutions may be sample-dependent .

What is the molecular weight and expression pattern of POF1B?

POF1B has a calculated molecular weight of 69 kDa, corresponding to 595 amino acids. In validation studies, the observed molecular weight also matches the predicted 69 kDa. The gene is identified by GenBank Accession Number BC017500, with NCBI Gene ID 79983 and UNIPROT ID Q8WVV4 . The protein shows differential expression patterns across tissues, with particularly notable expression in polarized epithelial tissues.

What are the optimal sample preparation protocols for POF1B detection in IHC?

For immunohistochemistry applications with POF1B antibody, specific antigen retrieval protocols have been validated:

• Primary recommendation: Antigen retrieval with TE buffer at pH 9.0

• Alternative method: Antigen retrieval with citrate buffer at pH 6.0

Positive IHC signals have been detected in human ovary cancer tissue and human stomach cancer tissue using these protocols . Researchers should optimize the antigen retrieval method based on their specific tissue samples to ensure consistent results.

How should POF1B antibody be stored to maintain optimal activity?

For maximum stability and performance, POF1B antibody should be:

• Stored at -20°C

• Kept in storage buffer containing PBS with 0.02% sodium azide and 50% glycerol at pH 7.3

• Expected stability: One year after shipment when properly stored

• For 20μl sizes, note that they contain 0.1% BSA

Importantly, aliquoting is unnecessary for -20°C storage of this particular antibody formulation .

How does POF1 function in cellular stress response pathways?

In yeast models, POF1 appears to play a critical role in cellular stress responses. Research has demonstrated that Δpof1 cells (with POF1 gene deletion) exhibit increased sensitivity to:

• Hydrogen peroxide

• Tert-butyl hydroperoxide

• Heat shock

• Protein unfolding agents (dithiothreitol and tunicamycin)

This suggests POF1's involvement in protecting cells against oxidative stress and protein misfolding events. Particularly intriguing is the finding that overexpression of POF1 suppressed the sensitivity of Δpct1 (a strain lacking phosphocholine cytidylyltransferase) to heat shock, indicating a functional relationship between these two proteins in stress adaptation mechanisms .

What is the relationship between POF1's ATPase activity and its biological function?

Biochemical analysis has revealed that purified POF1p exhibits significant ATPase activity (5 nmol of released phosphate per hour per μM enzyme), comparable to other ATPases involved in endoplasmic reticulum-associated degradation (ERAD). This activity was independent of phospholipid precursors, suggesting a mechanism distinct from classical phospholipid biosynthesis.

Co-immunoprecipitation experiments further demonstrated a physical interaction between POF1p and Ubc7p (an ubiquitin conjugating enzyme) in vivo. This interaction, combined with the ATPase activity profile, strongly suggests that POF1's biological function relates to regulation of protein degradation, potentially through ERAD or related quality control pathways .

What is the subcellular localization pattern of POF1 and how can it be visualized?

Immunocytochemistry studies have revealed a distinctive punctuated distribution pattern for POF1p in cells. This pattern becomes more pronounced in Δpct1 cells, coinciding with higher POF1p expression levels as confirmed by Western blotting.

Based on comparative analysis with known subcellular markers, researchers speculate that POF1p localizes primarily to the Golgi compartment. This localization pattern is consistent with potential roles in post-ER protein quality control pathways. The distinct non-uniform cytoplasmic distribution clearly differentiates it from nuclear or mitochondrial localization, as confirmed by DAPI counterstaining in merged images .

What are the validated positive controls for POF1B antibody applications?

For proper experimental design and validation, researchers should note these positive controls that have been successfully tested:

Using these validated controls provides a reliable benchmark for establishing experimental protocols and confirming antibody specificity .

How can researchers troubleshoot weak or inconsistent signals in POF1B detection?

When encountering weak signals in POF1B detection, consider these methodological approaches:

• For IHC applications:

  • Optimize antigen retrieval conditions (compare TE buffer pH 9.0 versus citrate buffer pH 6.0)

  • Increase antibody concentration gradually (within recommended ranges)

  • Extend primary antibody incubation time at 4°C

• For Western blot applications:

  • Ensure adequate protein loading (10-30 μg total protein)

  • Optimize blocking conditions to reduce background

  • Consider enhanced chemiluminescence detection systems for increased sensitivity

• For all applications:

  • Verify sample handling and storage conditions

  • Confirm antibody storage and handling procedures are followed

  • Test freshly prepared samples when possible

What evidence connects POF1B mutations to premature ovarian failure?

POF1B has been identified as a candidate gene for premature ovarian failure (POF), though the precise mechanisms require further research. Expression analysis shows that POF1B is mainly expressed in polarized epithelial tissues, including those in the ovarian system . Researchers investigating POF1B in reproduction-related disorders should consider:

• Examining POF1B expression patterns across different stages of ovarian development

• Analyzing POF1B mutations in patient cohorts with premature ovarian failure

• Investigating the actin cytoskeleton regulatory functions of POF1B in ovarian epithelial integrity

How does the protein quality control function of yeast POF1 relate to human cellular pathways?

The yeast POF1 protein has been implicated in protein quality control pathways, particularly in response to protein misfolding stressors. Research has shown that POF1 gene expression is significantly increased in cells treated with ER stress agents (DTT and tunicamycin), with this induction dependent on both Ire1p and Hac1p regulatory factors .

Additionally, cells treated with proteasome inhibitors show a four-fold induction of POF1 gene expression, further supporting its role in protein degradation pathways. Interestingly, yeast POF1 gene expression is repressed in Δopi1 strains, suggesting an involvement with membrane and protein metabolism coordination .

These findings point to evolutionarily conserved mechanisms that may have parallels in human cellular pathways, particularly those involving the unfolded protein response and endoplasmic reticulum-associated degradation.