TRUB2 Antibody

What is TRUB2 and what is its biological function?

TRUB2 is a minor enzyme that contributes to the isomerization of uridine to pseudouridine (pseudouridylation) of specific mitochondrial mRNAs such as COXI and COXIII mt-mRNAs . As a component of a functional protein-RNA module consisting of RCC1L, NGRN, RPUSD3, RPUSD4, FASTKD2, and 16S mitochondrial ribosomal RNA (16S mt-rRNA), TRUB2 controls 16S mt-rRNA abundance and is required for intra-mitochondrial translation . Additionally, it catalyzes pseudouridylation of some tRNAs, including synthesis of pseudouridine(55) from uracil-55 in the psi GC loop of a subset of tRNAs .

What types of TRUB2 antibodies are available for research?

Multiple types of TRUB2 antibodies are available with varying characteristics:

These antibodies differ in their conjugation status, with some available in conjugation-ready formats designed for fluorochromes, metal isotopes, oligonucleotides, and enzymes .

How to select the appropriate TRUB2 antibody for specific experimental applications?

When selecting a TRUB2 antibody, consider these methodological factors:

• Research application: Different antibodies are validated for specific applications:

  • For Western blotting: Most TRUB2 antibodies are validated for this technique (19891-1-AP recommended dilution: 1:1000-1:4000)

  • For IHC applications: Select antibodies validated for IHC (19891-1-AP or HPA021211)

  • For multiplex imaging: Consider conjugation-ready formats

• Species reactivity: Verify compatibility with your experimental model:

  • Human samples: All documented TRUB2 antibodies

  • Mouse/rat studies: Select antibodies with verified cross-reactivity

• Epitope considerations:

  • For studying specific domains: Choose antibodies targeting relevant regions

  • For detecting full-length protein: Select antibodies recognizing complete protein

• Validation evidence: Review performance data in target applications before purchase, including observed molecular weight (typically 37 kDa) .

How can TRUB2 antibodies be used to investigate mitochondrial pseudouridylation mechanisms?

TRUB2 antibodies can elucidate pseudouridylation mechanisms through several experimental approaches:

• Protein-RNA interaction studies:

  • UV cross-link cells to stabilize TRUB2-RNA interactions

  • Immunoprecipitate using TRUB2 antibodies following a protocol such as: extract in 50 mM Tris-HCl (pH 7.5), 150 mM NaCl, 1% taurodeoxycholate buffer

  • Pre-clear with non-coated beads to reduce non-specific binding

  • Incubate with antibody-conjugated beads overnight at 4°C

  • Analyze RNA modifications by sequencing

• Comparative analysis with TRUB1:

  • Studies using specific antibodies have revealed that TRUB2's activity differs from its paralog TRUB1:

    • TRUB2 (mitochondrial) requires both U54 and A58 to produce Ψ55 in tRNAs

    • TRUB1 (nuclear/cytoplasmic) can modify U55 regardless of U54 presence

    • TRUB2's Ψ55 activity is enhanced by m1A58 modification while TRUB1's is not

• Protein complex characterization:

  • BioID proximity labeling using TRUB2 antibodies identified a functional module including RCC1L, NGRN, RPUSD3, RPUSD4, and FASTKD2

  • This approach helped establish TRUB2's essential role in mitochondrial translation

What methodological approaches can resolve contradictory results when using different TRUB2 antibodies?

When faced with contradictory results using different TRUB2 antibodies, implement the following methodological approaches:

• Genetic validation controls:

  • Create TRUB2 knockout cells using CRISPR-Cas9 as definitive negative controls

  • Generate endogenously tagged TRUB2 cells (e.g., TRUB2-Flag) using CRISPR-Cas9 knock-in methodology :

    • Co-transfect crRNA/tracrRNA, Cas9 nuclease, and single-stranded oligo DNA (ssODN) containing tag sequences

    • Use HiBiT detection system to isolate successfully tagged cells

    • Validate by PCR and Western blotting with anti-Flag antibody

• Orthogonal detection methods:

  • Confirm antibody results using mass spectrometry

  • Correlate protein detection with RNA levels via RT-qPCR

  • Use targeted pseudouridylation assays to confirm functional activity

• Systematic antibody comparison:

  • Test multiple antibodies targeting different epitopes under identical conditions

  • Include relevant controls for each antibody:

    • Positive controls: HT-1080, HeLa, HepG2, or K-562 cells known to express TRUB2

    • Negative controls: TRUB2 knockdown samples

  • Document and compare specificity, sensitivity, and reproducibility

How do experimental conditions affect TRUB2 antibody performance in detecting protein-protein interactions?

For optimal detection of TRUB2 protein interactions, consider these experimental variables:

• Mitochondrial isolation techniques:

  • Differential centrifugation protocol:

    • Pellet cells at 800 rpm for 3 minutes

    • Centrifuge at 9,000 g at 4°C for 20 minutes to isolate mitochondria

    • Final centrifugation at 10,000 g to obtain mitochondrial pellet

• Cross-linking conditions:

  • For protein-protein interactions: Use membrane-permeable cross-linkers

  • For protein-RNA interactions: UV cross-link in a UV Stratalinker 1800 for 10 minutes on ice

• Extraction buffer composition:

  • Use 50 mM Tris-HCl, pH 7.5, 150 mM NaCl, 1% taurodeoxycholate with protease inhibitors

  • Alternative: extraction with 0.1 M glycine (pH 2.5) supplemented with 1% dodecyl maltoside

• Co-immunoprecipitation optimization:

  • Pre-clear extracts overnight with non-coated beads

  • Cross-link antibodies to beads for higher specificity

  • Perform immunoprecipitation overnight at 4°C for optimal complex formation

What are the specific requirements for using TRUB2 antibodies in pseudouridylation activity assays?

When designing pseudouridylation activity assays using TRUB2 antibodies, implement these methodological considerations:

• Substrate requirements:

  • TRUB2 activity depends on specific tRNA structural features:

    • Requires U54 and A58 in a reverse Hoogsteen pair configuration

    • Activity is enhanced by m1A58 modification

    • Cannot modify U55 in tRNAs with A54 (e.g., tRNA iMet)

• Detection strategies:

  • Combine immunoprecipitation with TRUB2 antibodies to isolate the enzyme

  • Use in vitro pseudouridylation assays with radiolabeled or chemically modified substrates

  • Quantify pseudouridine formation using thin-layer chromatography or mass spectrometry

• Control experiments:

  • Include TRUB1 as a related enzyme with different substrate requirements

  • Use substrate variants with mutations at key positions (U54A, A58G) to confirm specificity

  • Compare wild-type TRUB2 activity with catalytically inactive mutants

What are the optimal conditions for Western blotting with TRUB2 antibodies?

For optimal Western blotting results with TRUB2 antibodies, follow these methodological guidelines:

• Sample preparation:

  • Cell types: HT-1080, HeLa, HepG2, or K-562 cells have confirmed TRUB2 expression

  • Protein extraction: Use buffers containing 1% taurodeoxycholate or 1% dodecyl maltoside

  • Include complete protease inhibitors without EDTA during extraction

• Electrophoresis and transfer conditions:

  • Expected molecular weight: 37 kDa for TRUB2

  • Gel percentage: 10-12% polyacrylamide for optimal resolution

  • Transfer membrane: PVDF recommended for higher protein binding capacity

• Antibody dilutions:

  • Primary antibody:

    • Polyclonal TRUB2 antibody 19891-1-AP: 1:1000-1:4000

    • Other TRUB2 antibodies: 1:200-1:2000 range

  • Secondary antibody: HRP-conjugated anti-rabbit IgG at 1:5000-1:10,000

• Detection systems:

  • Standard ECL for routine detection

  • Enhanced chemiluminescence substrates for low-abundance detection

How to optimize immunofluorescence protocols for TRUB2 antibodies in mitochondrial localization studies?

For precise mitochondrial localization of TRUB2 using immunofluorescence:

• Fixation and permeabilization:

  • Fixative: 4% paraformaldehyde for 15-20 minutes at room temperature

  • Permeabilization: 0.2-0.5% Triton X-100 to ensure antibody access to mitochondria

  • Antigen retrieval: For tissue sections, use TE buffer pH 9.0

• Antibody conditions:

  • Primary antibody:

    • HPA021211: 0.25-2 μg/mL recommended concentration

    • Incubation: Overnight at 4°C for optimal penetration

  • Secondary antibody: Fluorophore-conjugated anti-rabbit IgG (1:500-1:1000)

  • Include DAPI (1:1000) for nuclear counterstaining

• Co-localization markers:

  • Include established mitochondrial markers (MitoTracker, TOMM20, or COX IV)

  • Perform sequential imaging to minimize bleed-through between channels

• Image acquisition and analysis:

  • Use confocal microscopy for optimal resolution of mitochondrial structures

  • Perform z-stack imaging (0.5-1 μm intervals) to capture complete mitochondrial networks

  • Quantify co-localization using Pearson's or Mander's coefficients

What controls are essential for validating TRUB2 antibody specificity?

Implement these critical controls to validate TRUB2 antibody specificity:

• Positive controls:

  • Cell lines with confirmed TRUB2 expression (HT-1080, HeLa, HepG2, K-562)

  • Overexpression systems with tagged TRUB2

  • Human colon cancer tissue (validated for IHC)

• Negative controls:

  • TRUB2 knockout generated by CRISPR-Cas9

  • siRNA/shRNA knockdown of TRUB2

  • Primary antibody omission

  • Isotype control antibodies

• Specificity controls:

  • Peptide competition assays using immunizing peptide

  • Testing for cross-reactivity with recombinant TRUB1

  • Sequential probing with antibodies targeting different TRUB2 epitopes

• Loading and technical controls:

  • For Western blots: Total protein normalization or mitochondrial markers

  • For IHC/IF: Adjacent sections with different antibodies

  • Batch controls to monitor inter-experimental variation

How to troubleshoot common issues with TRUB2 antibodies in experimental applications?

Address these common problems encountered with TRUB2 antibodies:

How have TRUB2 antibodies contributed to understanding mitochondrial RNA processing?

TRUB2 antibodies have enabled several breakthrough discoveries in mitochondrial RNA biology:

• Identification of a mitochondrial pseudouridine synthase module:

  • BioID proximity labeling and mass spectrometry using TRUB2 antibodies revealed:

    • TRUB2 interacts with RPUSD3, RPUSD4, NGRN, WBSCR16, and FASTKD2

    • This module controls 16S mt-rRNA abundance and mitochondrial translation

    • The module was independently confirmed in CRISPR/Cas9 screens for essential OXPHOS genes

• Elucidation of substrate specificity mechanisms:

  • TRUB2 antibody-based studies demonstrated:

    • TRUB2 requires both U54 and A58 for pseudouridylation activity

    • Its activity is enhanced by m1A58 modification

    • These requirements differ from its nuclear paralog TRUB1

• Discovery of essential role in cellular viability:

  • TRUB2 was identified as a core essential gene in multiple human cell lines

  • CRISPR/Cas9 screens with TRUB2 antibody validation revealed its critical importance in oxidative phosphorylation

What advances in pseudouridylation detection have been enabled by TRUB2 antibodies?

TRUB2 antibodies have facilitated important methodological advances in pseudouridylation research:

• Development of BACS (Biochemical Analysis of Cellular Status):

  • While not directly using TRUB2 antibodies, this technique can detect pseudouridine modifications introduced by pseudouridine synthases like TRUB2

  • Enables absolute quantification and base-resolution sequencing of pseudouridine sites

  • Has been applied to elucidate genuine Ψ targets and sequence motifs of key PUS enzymes

• Characterization of pseudouridylation in different RNA types:

  • TRUB2 antibodies helped establish that TRUB2 produces Ψ55 in mitochondrial tRNAs

  • This modification is essential for proper tRNA structure and function in mitochondrial translation

• Comparative analysis of pseudouridylation in different cellular compartments:

  • TRUB2 (mitochondrial) and TRUB1 (nuclear/cytoplasmic) have distinct substrate requirements and activities

  • These differences highlight the specialized roles of these paralogs in RNA modification within different cellular compartments

What future research directions can be explored using TRUB2 antibodies?

TRUB2 antibodies can facilitate several promising research directions:

• Investigation of TRUB2 in human disease:

  • Mitochondrial dysfunction is implicated in numerous pathologies

  • TRUB2 antibodies could help assess whether pseudouridylation defects contribute to mitochondrial diseases

  • Unlike TRIB2 antibodies (different protein) which have been associated with narcolepsy , the role of TRUB2 in disease remains largely unexplored

• Dynamics of mitochondrial RNA modification:

  • Studies on how cellular stress affects TRUB2 localization and activity

  • Investigation of potential post-translational modifications regulating TRUB2

  • Analysis of TRUB2 complex assembly and disassembly under different conditions

• Therapeutic targeting potential:

  • Given TRUB2's essential role in cellular viability, it could represent a potential therapeutic target

  • Antibody-based screening assays could identify compounds that modulate TRUB2 activity

  • Development of cell-penetrating antibodies or antibody fragments for functional studies

• Role in viral RNA modification:

  • Recent findings suggest differences in pseudouridylation between virus families

  • TRUB2 antibodies could help investigate whether mitochondrial tRNA modifications are altered during viral infection