Recombinant Xenopus tropicalis Transmembrane protein 147 (tmem147)

What is Xenopus tropicalis tmem147 and why is it used in research?

Xenopus tropicalis transmembrane protein 147 (tmem147) is a 225-amino acid protein that serves as a valuable research target in developmental biology studies. X. tropicalis has emerged as an important model organism due to its diploid genome and shorter generation time compared to Xenopus laevis, facilitating genetic and genomic research approaches . The recombinant full-length protein (Q28FY5) can be expressed with an N-terminal His tag in E. coli systems, making it accessible for various experimental applications . While specific functions of tmem147 in X. tropicalis are not fully characterized in the provided materials, transmembrane proteins typically play crucial roles in cellular signaling, membrane transport, and structural organization.

How does tmem147 expression compare to other genes during Xenopus tropicalis development?

While the search results don't specifically address tmem147 expression patterns, studies on other genes in X. tropicalis demonstrate that many developmental genes show tissue-specific and temporally regulated expression patterns rather than ubiquitous expression. For instance, ribosome biogenesis factors exhibit enrichment in specific tissues like cranial neural crest and ventral blood islands during development, with clear differences in timing, transcript number, and tissue localization . Researchers interested in tmem147 expression would likely benefit from examining its spatiotemporal regulation during embryonic development using techniques like in situ hybridization, similar to methodologies employed for studying other genes in X. tropicalis.

How should recombinant Xenopus tropicalis tmem147 be reconstituted and stored for maximum stability?

For optimal reconstitution and storage of recombinant X. tropicalis tmem147:

• Centrifuge the vial briefly before opening to bring contents to the bottom

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

• Add glycerol to a final concentration of 5-50% (with 50% being recommended)

• Aliquot for long-term storage at -20°C/-80°C to avoid repeated freeze-thaw cycles

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

The protein is supplied in a Tris/PBS-based buffer with 6% trehalose at pH 8.0, which helps maintain stability during storage .

What experimental techniques are most suitable for studying tmem147 function in Xenopus tropicalis?

Based on methodologies used for studying other genes in X. tropicalis, researchers can employ several approaches to investigate tmem147 function:

• In situ hybridization: To examine spatial and temporal expression patterns during development, following protocols similar to those used for studying ribosome biogenesis factors .

• Transgenic approaches: X. tropicalis offers advantages for generating stable transgenic lines due to its shorter generation time compared to X. laevis. This allows for multigenerational experiments to study gene function .

• CRISPR/Cas9 gene editing: For creating targeted mutations to study loss-of-function phenotypes.

• Tissue chimeras: X. tropicalis allows for the generation of tissue chimeras, combining mutant and wildtype tissues to determine tissue-specific functions, similar to approaches used for studying lens determination .

• High-resolution RNA-seq analysis: To measure transcript dynamics throughout embryogenesis, similar to approaches used for studying ribosome-associated genes .

How can SDS-PAGE be optimized for analysis of recombinant Xenopus tropicalis tmem147?

For optimal SDS-PAGE analysis of recombinant X. tropicalis tmem147:

• Sample preparation:

  • Reconstitute the lyophilized protein as recommended

  • Mix with appropriate loading buffer containing SDS and reducing agent

  • Heat at 95°C for 5 minutes to ensure complete denaturation

• Gel selection:

  • Use 12-15% polyacrylamide gels for better resolution of this 225-amino acid protein

  • Consider gradient gels (4-20%) for improved band sharpness

• Running conditions:

  • Run at 100-120V until the dye front reaches the bottom of the gel

  • Use standard Tris-glycine running buffer

• Visualization:

  • Coomassie blue staining for general protein detection

  • Western blotting with anti-His antibodies for specific detection of the His-tagged protein

  • Expected purity should be greater than 90% as indicated in the product specifications

How can researchers design experiments to investigate tmem147 developmental expression patterns in Xenopus tropicalis?

To investigate developmental expression patterns of tmem147 in X. tropicalis, researchers should consider a multi-method approach:

• Whole-mount in situ hybridization (WISH):

  • Obtain full-length tmem147 cDNA clones (similar to how other gene probes were obtained from Sanger/Wellcome Trust X. tropicalis cDNA libraries)

  • Generate digoxigenin-labeled antisense mRNA probes through in vitro transcription

  • Collect embryos at key developmental stages (similar to stages 3, 10, 15, 20-22, 28+ used for other genes)

  • Fix embryos in MEMFA for 1-2 hours at room temperature and dehydrate in ethanol

  • Perform hybridization following established protocols for X. tropicalis

  • Visualize using BM Purple staining

• High-resolution RNA-seq analysis:

  • Extract RNA from embryos at multiple developmental timepoints

  • Perform RNA sequencing with high temporal resolution

  • Analyze transcript numbers and expression dynamics throughout embryogenesis

  • Compare expression patterns with other developmentally regulated genes

  • Look for peaks of expression that may correspond to important developmental events, similar to patterns observed for ribosome biogenesis factors

• Quantitative PCR (qPCR):

  • Design primers specific to tmem147

  • Extract RNA from embryos at different developmental stages

  • Perform reverse transcription and qPCR

  • Normalize expression data to appropriate reference genes

What strategies can be employed to study potential interactions between tmem147 and other proteins in Xenopus tropicalis?

To investigate protein-protein interactions involving tmem147 in X. tropicalis:

• Co-immunoprecipitation (Co-IP):

  • Generate antibodies against tmem147 or use the His-tag for pull-down

  • Prepare protein lysates from X. tropicalis embryos or tissues

  • Perform immunoprecipitation followed by mass spectrometry to identify interacting partners

  • Validate interactions through reciprocal Co-IP experiments

• Proximity labeling approaches:

  • Generate fusion constructs of tmem147 with BioID or APEX2

  • Express in X. tropicalis embryos through microinjection

  • Perform biotin labeling, streptavidin pull-down, and mass spectrometry to identify proximal proteins

• Yeast two-hybrid screening:

  • Use tmem147 as bait to screen X. tropicalis cDNA libraries

  • Validate potential interactions through orthogonal methods

• FRET or BiFC analysis:

  • Generate fluorescent protein fusions with tmem147 and candidate interactors

  • Express in X. tropicalis embryos through microinjection

  • Image using confocal microscopy to assess protein-protein interactions in vivo

How can mutations in tmem147 be generated and characterized in Xenopus tropicalis?

To generate and characterize tmem147 mutations in X. tropicalis:

• CRISPR/Cas9-mediated mutagenesis:

  • Design guide RNAs targeting tmem147 exons

  • Microinject CRISPR/Cas9 components into one-cell stage embryos

  • Screen F0 embryos for mutations using T7 endonuclease assay or direct sequencing

  • Raise mosaic F0 animals to adulthood and breed to obtain F1 heterozygotes

  • Intercross F1 heterozygotes to obtain homozygous mutants in F2

• Morpholino knockdown:

  • Design antisense morpholinos targeting tmem147 mRNA

  • Validate specificity using rescue experiments with morpholino-resistant mRNA

  • Analyze phenotypes at relevant developmental stages

• Gynogenetic screening:

  • If a tmem147 mutation is identified, use gynogenetic screening to facilitate mapping

  • Generate haploid embryos by fertilizing with UV-irradiated sperm

  • Diploidize embryos using cold shock protocol

  • Screen for phenotypes associated with tmem147 mutation

  • Use the frequency of phenotype appearance to estimate distance from centromere

• Positional cloning and mapping:

  • Use simple sequence length polymorphisms (SSLPs) and the X. tropicalis genetic map to map mutations

  • Employ gynogenetic mapping to quickly identify the chromosome on which the mutation lies

How does tmem147 in Xenopus tropicalis compare to its orthologs in other model organisms?

While the search results don't provide specific information about tmem147 orthologs, comparative analysis approaches can be outlined based on methodologies used for other genes:

• Sequence conservation analysis:

  • Compare amino acid sequences between X. tropicalis tmem147 (Q28FY5) and orthologs from other species

  • Identify conserved domains, motifs, and potential functional regions

  • Use bioinformatics tools to predict transmembrane domains and protein topology

• Expression pattern comparison:

  • Compare developmental expression patterns between X. tropicalis and other model organisms

  • Analyze tissue-specific expression to identify conserved and divergent patterns

  • Examine whether expression peaks correlate with similar developmental events across species

• Functional complementation studies:

  • Test whether tmem147 from other species can rescue phenotypes in X. tropicalis tmem147 mutants

  • Assess conservation of protein function across evolutionary distance

The close relationship between X. tropicalis and X. laevis (diverged approximately 50 Mya) suggests that gene functions and expression patterns are likely conserved between these species, though X. laevis has undergone genome duplication .

What advantages does Xenopus tropicalis offer for studying tmem147 compared to other model systems?

X. tropicalis offers several advantages for studying tmem147:

• Diploid genome: Unlike X. laevis (allotetraploid) and zebrafish (which underwent genome duplication), X. tropicalis has a diploid genome that simplifies genetic analyses and more closely resembles mammalian gene organization .

• Shorter generation time: X. tropicalis reaches sexual maturity more quickly than X. laevis, facilitating multigenerational experiments such as creating stable transgenic lines and generating mutant lines .

• Embryological advantages:

  • Large, externally developing embryos allow for easy manipulation and observation

  • Ability to create tissue chimeras to study tissue-specific gene functions

  • Embryos produce large amounts of protein, facilitating biochemical analyses

• Genome resources: The X. tropicalis genome has been sequenced and annotated, providing valuable resources for genetic and genomic studies .

• Established genetic techniques: Methods for gynogenetic screening, mapping mutations, and positional cloning have been developed specifically for X. tropicalis .

What are common challenges when working with recombinant tmem147 protein and how can they be addressed?

Common challenges and solutions when working with recombinant tmem147:

• Protein solubility issues:

  • Challenge: As a transmembrane protein, tmem147 may have solubility issues

  • Solution: Consider using detergents (e.g., mild non-ionic detergents like Triton X-100 or DDM) during reconstitution and experiment procedures

  • Alternative: For certain applications, use protein solubilization additives like sarkosyl or urea

• Protein degradation:

  • Challenge: Proteolytic degradation during storage or experiments

  • Solution: Add protease inhibitors during handling and store in aliquots at -80°C

  • Recommendation: Avoid repeated freeze-thaw cycles as noted in product information

• Low protein yield:

  • Challenge: Insufficient protein amount for experiments

  • Solution: Optimize reconstitution concentration (0.1-1.0 mg/mL as recommended)

  • Alternative: Scale experiments appropriately based on available protein amount

• Detection difficulties:

  • Challenge: Weak signal in Western blotting or other detection methods

  • Solution: Utilize the N-terminal His tag for detection with anti-His antibodies

  • Alternative: Optimize blocking conditions and antibody concentrations

How can researchers troubleshoot expression analysis experiments for tmem147 in Xenopus tropicalis?

When troubleshooting expression analysis experiments:

• In situ hybridization issues:

  • Problem: Weak or nonspecific signal

  • Solution: Optimize probe concentration and hybridization temperature

  • Alternative: Try different probe lengths or regions of the tmem147 sequence

  • Control: Include positive control probes known to work in X. tropicalis

• RT-PCR/qPCR challenges:

  • Problem: Inconsistent amplification or unexpected results

  • Solution: Design multiple primer pairs targeting different regions of tmem147

  • Control: Include housekeeping genes as internal controls

  • Validation: Sequence PCR products to confirm specificity

• RNA-seq analysis difficulties:

  • Problem: Low read counts for tmem147

  • Solution: Increase sequencing depth or use targeted approaches

  • Analysis: Compare multiple biological replicates to confirm expression patterns

  • Validation: Confirm key findings with alternative methods like qPCR

• Antibody specificity issues:

  • Problem: Cross-reactivity or weak signal with anti-tmem147 antibodies

  • Solution: Validate antibodies using overexpression systems or knockout controls

  • Alternative: Use epitope tags (like the His tag in recombinant protein) for detection

What considerations are important when designing experiments to study tmem147 function during Xenopus tropicalis development?

Key considerations for studying tmem147 function during development:

• Developmental timing:

  • Select appropriate developmental stages based on potential expression patterns

  • Consider examining stages with high developmental activity (similar to peaks observed for ribosome biogenesis factors at gastrulation, stages 22-28, and stages 36-45)

• Spatial resolution:

  • Design experiments to detect tissue-specific expression and function

  • Consider sectioning embryos after in situ hybridization to examine expression at cellular resolution

• Functional redundancy:

  • Assess potential redundancy with related proteins that might compensate for tmem147 loss

  • Design experiments to address potential compensatory mechanisms

• Phenotypic analysis:

  • Develop clear criteria for analyzing mutant or knockdown phenotypes

  • Use appropriate control groups (e.g., siblings from the same mating)

  • Consider both morphological and molecular readouts

• Reproducibility:

  • Use multiple experimental approaches to validate findings

  • Include appropriate statistical analyses

  • Consider biological and technical replicates in experimental design