Recombinant Bovine UPF0458 protein C7orf42 homolog

What is UPF0458 protein C7orf42 homolog and what is its relationship to TMEM248?

UPF0458 protein C7orf42 homolog is the standard name for a transmembrane protein that in humans is encoded by the TMEM248 gene (Transmembrane protein 248). The name C7orf42 (Chromosome 7 open reading frame 42) was originally assigned before the protein's function was better characterized. This protein contains multiple transmembrane domains and is composed of seven exons. It is highly conserved across vertebrates and invertebrates, indicating evolutionary importance in cellular function .

What are the structural characteristics of UPF0458 protein C7orf42 homolog?

The UPF0458 protein C7orf42 homolog (TMEM248) is a multi-pass membrane protein with several key structural features:

• Protein length: The polypeptide chain consists of 314 amino acids in its canonical form

• Molecular weight: Approximately 35 kDa

• Composition characteristics: Threonine-rich protein (higher than average threonine residues)

• Isoelectric point: 5.91 pH (making it slightly acidic)

• Transmembrane regions: Multiple transmembrane domains allowing it to span cellular membranes

• Amino acid sequence (from rat homolog): The full amino acid sequence includes distinctive hydrophobic regions consistent with membrane-spanning domains

What is known about the subcellular localization of UPF0458 protein C7orf42 homolog?

Immunofluorescence staining and predictive analyses indicate that UPF0458 protein C7orf42 homolog (TMEM248) is primarily localized to:

• Endoplasmic reticulum membrane

• Vesicular structures within the cytoplasm

• Plasma membrane

This localization pattern is consistent with its predicted function in vesicular trafficking. The protein has been observed in vesicles through immunofluorescence staining techniques, supporting its role in membrane-associated cellular processes .

What post-translational modifications occur in UPF0458 protein C7orf42 homolog?

Several experimentally validated post-translational modifications have been identified in UPF0458 protein C7orf42 homolog (TMEM248):

These modifications likely regulate protein function, stability, localization, and protein-protein interactions, which are critical for understanding how this protein functions in different cellular contexts .

What expression patterns are observed for UPF0458 protein C7orf42 homolog across different tissues?

While UPF0458 protein C7orf42 homolog (TMEM248) shows ubiquitous expression throughout the body (low tissue specificity), there are notable differences in expression levels:

• Highest expression observed in: Thyroid, endometrium, prostate, testis, and ovaries

• Moderate expression in: Most other tissue types

• At the cellular level: Enriched expression in macrophages

This widespread expression pattern suggests a fundamental cellular function, while tissue-specific concentration may indicate specialized roles in certain organs .

What methodological approaches are recommended for expressing and purifying recombinant UPF0458 protein C7orf42 homolog?

For optimal expression and purification of recombinant UPF0458 protein C7orf42 homolog, the following methodological approach is recommended:

• Expression System Selection: E. coli has been successfully used for expressing recombinant forms of this protein. For more complex post-translational modifications, mammalian or insect cell systems may be preferable .

• Tag Configuration:

  • N-terminal His-tag has proven effective for purification via affinity chromatography

  • Consider tag position carefully as it may affect protein folding and function

• Purification Protocol:

  • Use immobilized metal affinity chromatography (IMAC) for initial purification

  • Follow with size exclusion chromatography to achieve >90% purity

  • Validate purity via SDS-PAGE analysis

• Storage Recommendations:

  • Store at -20°C/-80°C upon receipt

  • Avoid repeated freeze-thaw cycles by preparing working aliquots

  • For working aliquots, store at 4°C for up to one week

  • Reconstitute lyophilized protein in deionized sterile water to 0.1-1.0 mg/mL

  • Add 5-50% glycerol (final concentration) for long-term storage

How can researchers effectively investigate the functional role of UPF0458 protein C7orf42 homolog in vesicular trafficking?

To investigate the functional role of UPF0458 protein C7orf42 homolog in vesicular trafficking, researchers should consider a multi-faceted approach:

• Co-localization Studies:

  • Perform double immunofluorescence with known vesicular markers (e.g., Rab GTPases, SNARE proteins)

  • Use confocal microscopy to assess spatial overlap with specific vesicular compartments

• Protein Interaction Analysis:

  • Conduct co-immunoprecipitation experiments to identify binding partners

  • Perform proximity ligation assays to confirm interactions in situ

  • Consider BioID or APEX2 proximity labeling to identify the protein's neighborhood

• Loss-of-Function Studies:

  • Generate CRISPR/Cas9 knockout cell lines

  • Use siRNA/shRNA for transient knockdown

  • Assess effects on vesicular morphology, distribution, and dynamics

• Vesicle Trafficking Assays:

  • Monitor endocytosis/exocytosis rates using fluorescently labeled cargo

  • Assess vesicle movement using live-cell imaging

  • Measure vesicle fusion events using FRET-based reporters

• Structure-Function Analysis:

  • Create domain-specific mutations based on identified transmembrane regions

  • Generate constructs with modified post-translational modification sites

  • Assess the impact of these changes on localization and function

What experimental considerations should be addressed when studying the potential role of UPF0458 protein C7orf42 homolog in cancer development?

When investigating the potential oncogenic role of UPF0458 protein C7orf42 homolog (TMEM248), researchers should address several experimental considerations:

• Expression Analysis in Cancer Tissues:

  • Compare expression levels between matched tumor and normal tissues

  • Stratify analysis by cancer type, stage, and molecular subtype

  • Use both transcript (RNA-seq) and protein (immunohistochemistry) level analyses

• Correlation with Clinical Parameters:

  • Assess statistical associations with patient survival

  • Evaluate correlations with treatment response

  • Determine relationships with known prognostic factors

• Mechanistic Studies:

  • Investigate effects of overexpression in normal cell lines

  • Assess consequences of knockdown in cancer cell lines

  • Examine impact on:

    • Proliferation rates

    • Apoptosis resistance

    • Migration and invasion capacity

    • Anchorage-independent growth

• Pathway Integration:

  • Determine relationship with established oncogenic pathways

  • Assess effects on signal transduction cascades

  • Identify downstream effectors using phosphoproteomics

• In Vivo Models:

  • Generate transgenic models with altered expression

  • Use patient-derived xenografts with varying expression levels

  • Employ orthotopic models to assess tissue-specific effects

How can researchers effectively compare orthologs of UPF0458 protein C7orf42 homolog across different species for evolutionary studies?

To effectively compare orthologs of UPF0458 protein C7orf42 homolog across species for evolutionary analysis, researchers should implement the following methodological approach:

• Sequence Alignment and Conservation Analysis:

  • Perform multiple sequence alignment of orthologs from diverse species

  • Identify conserved domains, motifs, and critical residues

  • Calculate conservation scores across the protein length

  • Use tools like CLUSTAL Omega, T-Coffee, or MUSCLE for alignment

• Phylogenetic Analysis:

  • Construct phylogenetic trees using maximum likelihood or Bayesian methods

  • Calculate evolutionary distances between orthologs

  • Identify lineage-specific adaptations

  • Assess selective pressure across different domains (dN/dS ratios)

• Structural Comparison:

  • Generate protein structure predictions for different orthologs

  • Compare tertiary structures and identify conserved structural elements

  • Analyze differences in transmembrane domain arrangements

• Functional Domain Analysis:

  • Compare post-translational modification sites across orthologs

  • Assess conservation of functional motifs

  • Analyze species-specific insertions or deletions

• Expression Pattern Comparison:

  • Compare tissue distribution patterns across species

  • Analyze temporal expression during development

  • Assess expression under various physiological conditions

Currently, homologs have been identified and studied in various species including human, rat, bovine, and zebrafish (Danio rerio), indicating strong evolutionary conservation across vertebrates .

What are the optimal approaches for studying the post-translational modifications of UPF0458 protein C7orf42 homolog and their functional significance?

To comprehensively study post-translational modifications (PTMs) of UPF0458 protein C7orf42 homolog and determine their functional significance, researchers should employ the following approaches:

• PTM Site Identification:

  • Perform mass spectrometry-based proteomic analysis

  • Use enrichment techniques specific to each modification:

    • Phosphopeptide enrichment with TiO₂ or IMAC

    • Glycopeptide enrichment with lectin affinity

    • Ubiquitylated peptide enrichment with anti-K-ε-GG antibodies

  • Combine bottom-up and top-down proteomics for comprehensive coverage

• Site-Directed Mutagenesis:

  • Generate site-specific mutants at identified PTM sites:

    • For phosphorylation: S/T/Y to A (phospho-null) or E/D (phospho-mimetic)

    • For glycosylation: N to Q mutations

    • For ubiquitylation: K to R mutations

  • Assess effects on protein stability, localization, and function

• Dynamic PTM Analysis:

  • Study PTM changes in response to cellular stimuli

  • Monitor temporal dynamics using pulse-chase labeling

  • Investigate cross-talk between different modifications

• Structural Impact Assessment:

  • Use structural modeling to predict how PTMs affect protein conformation

  • Perform limited proteolysis to assess changes in protein folding

  • Employ hydrogen-deuterium exchange mass spectrometry to detect structural changes

• Functional Consequence Analysis:

  • Assess impact of PTM site mutations on:

    • Protein-protein interactions

    • Subcellular localization

    • Protein stability and half-life

    • Vesicular trafficking functions

Known PTM sites that should be prioritized include ubiquitylation (K228, K240, K245), glycosylation (N80), and phosphorylation (Y13, S300) .

What are the recommended reconstitution and storage protocols for lyophilized recombinant UPF0458 protein C7orf42 homolog?

For optimal handling of lyophilized recombinant UPF0458 protein C7orf42 homolog, the following reconstitution and storage protocols are recommended:

• Reconstitution Procedure:

  • Briefly centrifuge the vial prior to opening to bring contents to the bottom

  • Reconstitute in deionized sterile water to a concentration of 0.1-1.0 mg/mL

  • For long-term storage, add glycerol to a final concentration of 5-50% (50% is standard)

  • Avoid vigorous shaking or vortexing to prevent protein denaturation

• Storage Recommendations:

  • Stock solution: Store at -20°C/-80°C

  • Working aliquots: Store at 4°C for up to one week

  • Avoid repeated freeze-thaw cycles by preparing multiple small aliquots

  • For shipping and handling, maintain cold chain requirements

• Quality Control Checks:

  • Verify protein integrity by SDS-PAGE after reconstitution

  • Check activity using appropriate functional assays

  • Monitor aggregation state if applicable to your experimental system

• Buffer Considerations:

  • Standard storage buffer contains Tris/PBS with 6% Trehalose, pH 8.0

  • For specific applications, buffer exchange may be performed using dialysis or desalting columns

What are the key differences between recombinant UPF0458 protein C7orf42 homologs derived from different species, and how might these impact experimental design?

Understanding the differences between UPF0458 protein C7orf42 homologs from various species is crucial for experimental design. Key differences and their experimental implications include:

• Sequence Variation:

  • While core functional domains are conserved, species-specific variations exist

  • The rat homolog is 314 amino acids in length, similar to the human protein

  • Sequence identity comparisons:

  Species Comparison	Sequence Identity	Similarity
  Human vs. Rat	~85%	~92%
  Human vs. Bovine	~90%	~95%
  Human vs. Zebrafish	~70%	~82%

• Post-translational Modification Differences:

  • Conservation of key PTM sites varies between species

  • Consider species-specific PTM patterns when designing experiments

• Experimental Design Implications:

  • Selection of appropriate animal models should consider homology level

  • Antibody cross-reactivity may vary based on epitope conservation

  • For structure-function studies, consider species-specific domains

  • When making translational claims from animal studies to human applications, account for species differences

  • For heterologous expression, codon optimization may be necessary

• Expression System Considerations:

  • E. coli has been successfully used for expressing several species' homologs

  • For species-specific glycosylation patterns, consider mammalian expression systems

  • Yield and solubility may vary between homologs from different species

How can researchers effectively troubleshoot expression and purification challenges with recombinant UPF0458 protein C7orf42 homolog?

When encountering challenges in the expression and purification of recombinant UPF0458 protein C7orf42 homolog, researchers should systematically address potential issues using the following troubleshooting approach:

• Low Expression Yield:

  • Optimize codon usage for the expression host

  • Test different induction conditions (temperature, inducer concentration, duration)

  • Evaluate alternate promoter systems

  • Consider co-expression with chaperones for improved folding

  • Try different E. coli strains (BL21, Rosetta, Origami) for improved expression

• Poor Solubility:

  • Adjust lysis buffer composition (salt concentration, pH, detergents)

  • For this transmembrane protein, include appropriate detergents (DDM, CHAPS, or Triton X-100)

  • Lower induction temperature (16-20°C) to slow folding and improve solubility

  • Consider fusion tags that enhance solubility (SUMO, MBP, or GST)

  • Test different solubilization conditions for inclusion bodies if necessary

• Purification Challenges:

  • For His-tagged protein, optimize imidazole concentration in binding and elution buffers

  • Add low concentrations of detergent in all purification buffers

  • Include reducing agents if protein contains cysteines

  • Consider on-column refolding for proteins recovered from inclusion bodies

  • Implement additional purification steps (ion exchange, size exclusion) for higher purity

• Protein Stability Issues:

  • Add glycerol (5-20%) to stabilize purified protein

  • Include appropriate protease inhibitors during purification

  • Test different buffer systems for improved stability

  • Add stabilizing agents like trehalose (currently used at 6% in storage buffer)

  • Consider flash-freezing aliquots in liquid nitrogen

• Quality Control Approaches:

  • Verify protein identity by mass spectrometry

  • Assess purity by SDS-PAGE (aim for >90% purity)

  • Check for proper folding using circular dichroism

  • Validate functionality through appropriate activity assays

What analytical techniques are most appropriate for characterizing protein-protein interactions involving UPF0458 protein C7orf42 homolog?

To effectively characterize protein-protein interactions (PPIs) involving UPF0458 protein C7orf42 homolog (TMEM248), researchers should employ a multi-technique approach that addresses both in vitro and in vivo interactions:

• Affinity-based Methods:

  • Co-immunoprecipitation (Co-IP) with tagged recombinant protein

  • Pull-down assays using the His-tagged recombinant protein as bait

  • Tandem affinity purification for complex interaction networks

  • Experimental design should account for the transmembrane nature of the protein

• Label-based Proximity Detection:

  • BioID or TurboID proximity labeling to identify neighboring proteins

  • APEX2-based proximity labeling for temporally controlled interaction mapping

  • Split-protein complementation assays (BiFC, split-luciferase) for validation

• Biophysical Interaction Analysis:

  • Surface plasmon resonance (SPR) for binding kinetics

  • Isothermal titration calorimetry (ITC) for thermodynamic parameters

  • Microscale thermophoresis (MST) for interactions in solution

  • For membrane proteins, consider using nanodiscs or liposomes as membrane mimetics

• Structural Approaches:

  • Cryo-electron microscopy for larger complexes

  • X-ray crystallography for high-resolution interaction interfaces

  • NMR spectroscopy for dynamic interaction analysis

  • Cross-linking mass spectrometry to map interaction surfaces

• In silico Predictions and Validation:

  • Molecular docking simulations to predict interaction interfaces

  • Network analysis to identify potential interaction partners

  • Validate predictions experimentally using site-directed mutagenesis of predicted interface residues

How can researchers design experiments to investigate the role of UPF0458 protein C7orf42 homolog in specific disease models?

To investigate the role of UPF0458 protein C7orf42 homolog (TMEM248) in disease models, particularly in cancer where it shows differential expression, researchers should design experiments that establish causality and mechanism:

• Expression Modulation Strategies:

  • Gain-of-function studies:

    • Stable overexpression using lentiviral/retroviral systems

    • Inducible expression systems (Tet-On/Off) for temporal control

    • Tissue-specific expression in animal models

  • Loss-of-function studies:

    • CRISPR/Cas9 knockout cell lines and animal models

    • siRNA/shRNA knockdown for acute depletion

    • Dominant-negative mutant expression

• Disease-Specific Model Selection:

  • For cancer studies:

    • Cell line panels representing different cancer types (colon, breast, lung, ovarian, brain, renal)

    • Patient-derived organoids for greater physiological relevance

    • Xenograft models to assess in vivo tumor growth

    • Genetically engineered mouse models for tissue-specific effects

• Phenotypic Characterization:

  • Proliferation and cell cycle analysis

  • Apoptosis and cell death assessment

  • Migration and invasion assays

  • Anchorage-independent growth

  • In vivo metastasis models

  • Response to therapeutic agents

• Mechanistic Investigations:

  • Transcriptome analysis to identify affected pathways

  • Proteomics to determine alterations in protein expression and PTMs

  • Metabolomics to assess impact on cellular metabolism

  • Interactome analysis to identify disease-specific interaction partners

• Translational Relevance Assessment:

  • Correlation with patient data and outcomes

  • Evaluation as potential biomarker

  • Assessment as therapeutic target

  • Development of targeting strategies (antibodies, small molecules)

What considerations are important when designing antibodies against UPF0458 protein C7orf42 homolog for research applications?

When designing antibodies against UPF0458 protein C7orf42 homolog (TMEM248) for research applications, consider the following critical factors to ensure specificity, sensitivity, and experimental utility:

• Epitope Selection Strategy:

  • Target extracellular domains for live-cell applications

  • Consider cytoplasmic regions for fixed cell studies

  • Avoid highly conserved regions if species specificity is required

  • Target unique regions to avoid cross-reactivity with related proteins

  • Consider accessibility of epitopes in the native conformation

  • Analyze post-translational modification sites that might interfere with antibody binding

• Antibody Format Considerations:

  • Monoclonal antibodies for high specificity and reproducibility

  • Polyclonal antibodies for multiple epitope recognition

  • Recombinant antibodies for consistent production

  • Single-chain variable fragments (scFvs) for improved tissue penetration

  • Consider species compatibility for secondary antibody selection

• Validation Requirements:

  • Confirm specificity using knockout/knockdown controls

  • Validate cross-reactivity with orthologs from different species

  • Test in multiple applications (Western blot, IF, IP, IHC)

  • Verify epitope accessibility in different fixation conditions

  • Determine detection limits and optimal working concentrations

• Application-Specific Considerations:

  • For immunofluorescence: Test different fixation methods (aldehyde vs. alcohol-based)

  • For immunoprecipitation: Validate under native and denaturing conditions

  • For flow cytometry: Ensure epitope accessibility on intact cells

  • For proximity ligation assays: Test antibody pairs from different species

• Production Considerations:

  • Use the His-tagged recombinant protein for immunization and screening

  • Consider carrier proteins for improved immunogenicity

  • Test affinity purification against the immunogen

  • Evaluate lot-to-lot consistency for reproducible results

What are the most promising future research directions for understanding the function of UPF0458 protein C7orf42 homolog in cellular biology?

Based on current knowledge of UPF0458 protein C7orf42 homolog (TMEM248), several promising research directions emerge for advancing our understanding of this protein's role in cellular biology:

• Comprehensive Interactome Mapping:

  • Identify protein interaction networks across different cellular contexts

  • Determine tissue-specific and condition-dependent interactions

  • Establish the protein's position within vesicular trafficking pathways

• Functional Characterization in Model Organisms:

  • Develop knockout animal models to assess developmental and physiological roles

  • Utilize tissue-specific conditional knockout approaches to avoid embryonic lethality

  • Implement CRISPR/Cas9-mediated tagging for live-cell visualization

• Structure-Function Relationship Studies:

  • Determine high-resolution structural information through cryo-EM or X-ray crystallography

  • Map functional domains through systematic mutagenesis

  • Investigate the impact of post-translational modifications on structure

• Role in Disease Pathogenesis:

  • Explore mechanistic connections to cancer development and progression

  • Investigate potential roles in other diseases with vesicular trafficking defects

  • Assess therapeutic potential as a biomarker or drug target

• Evolutionary Analysis:

  • Conduct comprehensive phylogenetic studies across diverse species

  • Investigate functional divergence across evolutionary lineages

  • Identify conserved regulatory mechanisms

These research directions would significantly advance our understanding of this highly conserved protein and potentially reveal novel insights into fundamental cellular processes, disease mechanisms, and therapeutic opportunities .