tmem170a Antibody
Description
What is TMEM170A Antibody?
TMEM170A antibodies are polyclonal or monoclonal antibodies that specifically bind to the TMEM170A protein, a 15.25 kDa transmembrane protein with three transmembrane domains. These antibodies are used to investigate TMEM170A's role in regulating ER structure, nuclear envelope dynamics, and nuclear pore complex (NPC) formation . The protein’s C-terminus is cytoplasmic, and its N-terminus is luminal, as confirmed by topology prediction and immunofluorescence studies .
Role in ER Morphogenesis
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ER Sheet Promotion: TMEM170A overexpression increases ER sheet formation, while its silencing induces tubular ER, as shown by reduced CLIMP-63 (an ER-sheet marker) levels (28.47% of controls, P = 6.89×10⁻⁵) .
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Antagonism with Reticulon 4 (RTN4): TMEM170A interacts with RTN4, a tubule-promoting protein. Co-silencing both rescues ER morphology defects, indicating opposing roles in membrane shaping .
Nuclear Envelope and NPC Regulation
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NPC Density Reduction: TMEM170A knockdown decreases nuclear pore density (69.58% of controls) and reduces nucleoporins like Nup62 (29.49% of controls, P = 0.0009) .
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INM Protein Mislocalization: Silencing TMEM170A disrupts inner nuclear membrane (INM) protein localization (e.g., LBR relocalizes to ER aggregates in >80% of cells) .
Applications in Research
Product Specs
**Constituents:** 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
Q&A
How to validate TMEM170A antibody specificity in Western blot assays?
Validation requires a multi-step approach:
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Knockdown controls: Use siRNA targeting TMEM170A in HeLa K or U2OS cells. A validated antibody should show ≥70% signal reduction in Western blots compared to scrambled siRNA controls .
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Cross-reactivity testing: Assess reactivity against homologous proteins (e.g., TMEM170B) using overexpression lysates. The goat polyclonal antibody (STJ140293) shows no cross-reactivity with TMEM170B in mouse spleen and Jurkat cell lysates .
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Epitope mapping: For N-terminal antibodies like STJ140293, confirm binding using truncated TMEM170A constructs. The 40aa N-terminal epitope should produce no signal when deleted .
Table 1: Validation Parameters for STJ140293 Antibody
What controls are essential for TMEM170A localization studies?
Three critical controls:
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Permeabilization validation: Use digitonin (pore-forming) vs Triton X-100 (membrane dissolution). TMEM170A’s cytoplasmic C-terminus requires digitonin-only permeabilization for antibody access .
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Co-staining with ER markers: Mandatory co-localization with calnexin (ER lumen) and RTN4 (tubular ER). In TMEM170A-silenced cells, expect ≤30% overlap with RTN4 vs 85% in controls .
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Nuclear envelope controls: Include LAP2β or emerin staining. TMEM170A knockdown reduces nuclear rim LAP2β signal by 70% while increasing ER aggregation .
How to design experiments analyzing TMEM170A’s role in ER sheet-tubule balance?
Follow this protocol:
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Modulation models:
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Quantitative imaging:
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Rescue experiments: Co-silence RTN4 (1:1 siRNA ratio) to normalize ER morphology within 48h .
Table 2: ER/Nuclear Phenotypes of TMEM170A Modulation
| Parameter | Control | TMEM170A siRNA | TMEM170A Overexpression |
|---|---|---|---|
| ER Sheet/Tubule Ratio | 1:3 | 1:9 | 3:1 |
| Nuclear Surface Area | 622.2 ±6.87 μm² | 906.6 ±36.5 μm² | 522.1 ±15.9 μm² |
| NPC Density (ELYS) | 28.4 ±1.06 AU/μm | 19.8 ±0.74 AU/μm | 32.1 ±1.2 AU/μm |
| LBR Localization | 95% nuclear rim | 80% ER aggregates | 98% nuclear rim |
How to resolve contradictory findings about TMEM170A’s role in cancer?
Address context-dependent effects:
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Tissue-specific roles: While TMEM170A silencing causes 90% cell death in HeLa K , its downregulation in pancreatic cancer correlates with poor differentiation (p<0.05) . Always compare isoform expression—TMEM170B shows tumor-suppressive effects in breast cancer .
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Experimental models:
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Stratify clinical data: In PAAD, TMEM170A expression associates with survival (HR=1.34) but requires IHC validation in FFPE sections .
What methodologies confirm TMEM170A-RTN4 functional antagonism?
A three-pronged approach:
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Co-IP/MS: Immunoprecipitate FLAG-TMEM170A and identify RTN4 in eluates (≥2 unique peptides required)
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Morphometric analysis: Simultaneous siRNA against both proteins should restore:
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Live-cell imaging: Express GFP-RTN4 and mCherry-TMEM170A. Time-lapse tracks show opposed membrane curvature induction within 15min of drug-induced ER stress.
