Recombinant Saccharomyces cerevisiae Putative uncharacterized protein YLR171W (YLR171W)

What is the amino acid sequence and structural characteristics of YLR171W?

YLR171W is a putative uncharacterized protein from Saccharomyces cerevisiae (baker's yeast) with 129 amino acids. The complete amino acid sequence is:

MSSSQTLPKYVSIVSTVRWIISKVSSSSLSTSGVIPTIKYRLAYRLYCTLWSLYSMMLHILGFLANIVGVKSFTIFAFSPADIAVYHFFNLIFPCLETSNKYFNCVILCTCVSVYNLLQDRSCSWLKLLL

The protein appears to have several hydrophobic regions suggesting potential membrane association, though detailed structural analysis through crystallography or NMR has not been reported in the available literature. Preliminary sequence analysis indicates the presence of potential transmembrane domains and signal peptides that warrant further investigation through experimental validation.

What expression systems are most effective for producing recombinant YLR171W?

• E. coli expression system: Currently used for commercial production of His-tagged YLR171W . This system offers high yield but may lack proper post-translational modifications present in the native yeast environment.

• S. cerevisiae expression system: For maintaining native post-translational modifications, researchers can utilize systems similar to those described for other yeast proteins. The EBY100 strain [MATa AGA1::GAL1-AGA1::URA3 ura3–52 trp1 leu2-delta200 his3-delta200 pep4::HIS3 prb11.6R can1 GAL] has been successfully used for expression and secretion of heterologous proteins .

• Secretion methodology: When expressing in S. cerevisiae, researchers can employ the α-factor secretion signal sequence approach. This involves cloning the YLR171W sequence into appropriate vectors such as pVSec-based plasmids downstream of the MFα1 secretion sequence .

For optimal expression, culture conditions should include growth at 25-30°C with induction for 36-48 hours, followed by centrifugation, filtration, and concentration steps .

What purification strategies yield the highest purity and activity for YLR171W?

Purification of recombinant YLR171W requires a systematic approach based on its biochemical properties:

• Affinity chromatography: For His-tagged YLR171W, immobilized metal affinity chromatography (IMAC) using Ni-NTA resins provides an efficient first purification step .

• Size exclusion chromatography: Following affinity purification, this method helps remove aggregates and truncated forms while changing buffer conditions to those optimal for downstream applications.

• Concentration and storage: After purification, the protein can be concentrated using ultrafiltration with appropriate molecular weight cut-off (30kDa has been used successfully for similar yeast proteins) . Storage in Tris-based buffer with 50% glycerol at -20°C helps maintain stability .

The purification protocol should include quality control steps such as SDS-PAGE to assess purity and Western blotting to confirm identity. Researchers should be aware that the specific tag used during production (His-tag being common) may influence protein behavior and should be considered when interpreting results .

How can protein-protein interactions of YLR171W be identified and validated?

Given the uncharacterized nature of YLR171W, identifying interaction partners is crucial for functional elucidation:

• Yeast two-hybrid screening: Comprehensive two-hybrid analysis has been successfully employed to explore the yeast protein interactome . For YLR171W, using this system allows systematic screening against all possible proteins in S. cerevisiae to identify potential binding partners.

• Co-immunoprecipitation: For validating interactions detected through two-hybrid screening, researchers can perform co-IP experiments using antibodies against YLR171W or its tagged version.

• Pull-down assays: Utilizing recombinant His-tagged YLR171W as bait in pull-down experiments from yeast cell lysates can identify physiologically relevant interacting proteins.

• Proximity-based labeling: Newer techniques such as BioID or APEX2 can be employed by fusing these enzymes to YLR171W to identify proteins in close proximity in vivo.

When interpreting interaction data, researchers should consider the comprehensive nature of studies like the one mentioned in search result , which identified 4,549 two-hybrid interactions among 3,278 yeast proteins. Cross-validation using multiple methods strengthens confidence in identified interactions.

What computational approaches can predict potential functions of YLR171W?

For uncharacterized proteins like YLR171W, computational analyses offer valuable insights:

• Sequence homology analysis: Comparing YLR171W sequence against characterized proteins across species can identify functional domains and potential evolutionary relationships.

• Structural prediction: Tools like AlphaFold2 can predict three-dimensional structure, which may suggest functional motifs not apparent from sequence alone.

• Gene neighborhood analysis: Examining genes adjacent to YLR171W in the yeast genome can provide clues about potential functional relationships or operonic organization.

• Gene expression correlation analysis: Identifying genes whose expression patterns correlate with YLR171W across various conditions suggests potential functional relationships.

• Gene Ontology (GO) term prediction: Based on partial information about YLR171W, GO term prediction tools can suggest potential molecular functions, biological processes, or cellular components.

These computational predictions should be treated as hypotheses requiring experimental validation but provide valuable direction for focused experimental design.

How should researchers design experiments to elucidate the function of YLR171W?

A strategic experimental approach for characterizing YLR171W should include:

• Gene knockout/knockdown studies: Creating YLR171W-null mutants in S. cerevisiae followed by phenotypic characterization across various growth conditions can reveal physiological importance.

• Overexpression studies: Complementary to deletion studies, overexpression can reveal gain-of-function phenotypes that provide functional insights.

• Localization studies: Determining subcellular localization through GFP-fusion or immunolocalization provides context for potential functions.

• Interactome mapping: As discussed earlier, identifying protein interaction partners through multiple complementary methods.

• Transcriptional response analysis: Examining genome-wide transcriptional changes in response to YLR171W manipulation.

When designing these experiments, researchers should consider both hypothesis-driven approaches based on computational predictions and unbiased screening approaches to capture unexpected functions.

How can researchers handle conflicting results when studying YLR171W?

When faced with conflicting data about YLR171W, researchers should apply a systematic approach:

Most importantly, researchers should transparently report and discuss discrepancies rather than selectively reporting data that supports a particular hypothesis .

What approaches can integrate proteomic and genomic data for comprehensive understanding of YLR171W?

Integrating multiple omics data types provides richer insights into YLR171W function:

• Multi-omics data integration: Combine proteomic, transcriptomic, and genomic data to build a comprehensive functional profile.

• Network analysis: Place YLR171W in the context of protein-protein interaction networks, metabolic networks, and genetic interaction networks to identify functional modules.

• Condition-specific analysis: Compare omics data across different conditions to identify context-dependent behaviors of YLR171W.

• Evolutionary analysis: Compare YLR171W across fungal species to identify conserved features that suggest functional importance.

• Machine learning approaches: Apply supervised and unsupervised learning techniques to identify patterns in multi-omics data that may reveal hidden functional aspects.

This integrative approach is particularly valuable for uncharacterized proteins like YLR171W, where individual data types may provide only partial insights.

How can surface display techniques be applied to study YLR171W?

Surface display methodology offers unique advantages for studying proteins like YLR171W:

• Construction of surface display strains: Similar to approaches used for other yeast proteins, YLR171W can be fused to surface anchoring proteins like α-agglutinin. This involves amplifying the C-terminal half of the α-agglutinin surface anchoring protein and ligating it downstream of YLR171W in appropriate plasmids .

• Transformation and expression: After constructing surface display plasmids, transformation into S. cerevisiae followed by expression under appropriate conditions (typically 25-30°C for 36-48 hours) .

• Functional analysis on cell surface: With YLR171W displayed on the yeast cell surface, researchers can perform binding studies, enzymatic assays, or antibody epitope mapping directly on intact cells.

• Applications: Surface display is particularly valuable for studying potential membrane-associated functions of YLR171W or for developing biosensors based on this protein.

The construction of such display systems follows established protocols similar to those used for hemicellulases and other yeast proteins .

What are the potential cellular pathways that might involve YLR171W based on current evidence?

Although YLR171W remains largely uncharacterized, available evidence suggests several potential pathways:

Researchers should design experiments to systematically test these potential pathway associations, using both targeted approaches based on the pathways listed above and untargeted approaches to capture unexpected functions.