Recombinant Saccharomyces cerevisiae Uncharacterized membrane protein YDL180W (YDL180W)

What is YDL180W and what are its basic molecular characteristics?

YDL180W is an uncharacterized membrane protein from Saccharomyces cerevisiae (baker's yeast) consisting of 547 amino acids. The protein is identified by UniProt ID Q12301 and is classified as a transmembrane helical (TMH) protein. Based on available information, YDL180W has no clearly defined biological function yet, but cellular component Gene Ontology annotations suggest it localizes to membrane structures . The complete amino acid sequence starts with MVRLNHAASYFMPIFCSTR and contains predicted transmembrane domains that suggest its integration into cellular membranes .

What expression systems are most effective for producing recombinant YDL180W?

E. coli expression systems have been successfully used to produce recombinant YDL180W with N-terminal His tags . The protein can be expressed as a full-length construct (1-547 amino acids) and purified using affinity chromatography. When expressing transmembrane proteins like YDL180W, it's critical to optimize expression conditions to prevent protein aggregation and maintain proper folding. For research requiring higher yields or specific post-translational modifications, alternative expression systems such as yeast-based expression (homologous expression) might provide better results for membrane proteins, though this must be empirically determined for YDL180W specifically.

How stable is purified recombinant YDL180W and what are optimal storage conditions?

Purified recombinant YDL180W is typically supplied as a lyophilized powder and should be reconstituted in deionized sterile water to a concentration of 0.1-1.0 mg/mL . For long-term storage, adding glycerol to a final concentration of 50% and storing at -20°C/-80°C is recommended. The protein shows stability issues with repeated freeze-thaw cycles, which should be avoided . Working aliquots can be stored at 4°C for up to one week. The storage buffer typically consists of Tris/PBS-based buffer with 6% Trehalose at pH 8.0 .

What are the most effective solubilization methods for YDL180W as a membrane protein?

As a transmembrane protein, YDL180W requires appropriate detergents for solubilization while maintaining native-like conformations. While specific detergent screening data for YDL180W is not provided in the search results, transmembrane helical proteins similar to YDL180W typically respond well to mild detergents such as n-dodecyl-β-D-maltoside (DDM), n-decyl-β-D-maltoside (DM), or lauryl maltose neopentyl glycol (LMNG). A methodological approach would involve:

• Initial screening with multiple detergent types at various concentrations

• Assessing protein stability using techniques like size exclusion chromatography

• Optimizing solubilization conditions by testing detergent:protein ratios

• Potentially exploring lipid nanodiscs or amphipols for enhanced stability

These approaches should be empirically optimized specifically for YDL180W to maintain its structural integrity during purification and subsequent experiments.

What techniques are most suitable for studying the topology and membrane orientation of YDL180W?

Several complementary approaches can be employed to characterize YDL180W's membrane topology:

• Cysteine scanning mutagenesis: Introducing cysteine residues at various positions, followed by accessibility testing with membrane-permeable and impermeable reagents

• Protease protection assays: Determining which regions are protected from proteolytic digestion when the protein is in membrane environments

• Fluorescence techniques: Using environment-sensitive fluorophores attached to specific residues to determine their localization relative to the membrane

• Computational prediction: Utilizing transmembrane prediction algorithms in combination with experimental validation

These methods collectively provide information about which segments span the membrane and their orientation, crucial for understanding YDL180W's structural arrangement and potential functional mechanisms .

How can researchers effectively design experiments to investigate potential functions of this uncharacterized protein?

A systematic approach to functional characterization of YDL180W should include:

• Genetic interaction analysis: Expanding on the known genetic interaction with SWT1 to identify functional pathways through synthetic genetic array (SGA) analysis

• Transcriptome analysis: Examining gene expression changes in YDL180W deletion/overexpression strains

• Localization studies: Using fluorescent protein tagging to determine precise subcellular localization

• Phenotypic profiling: Subjecting deletion mutants to various growth conditions to identify conditions where YDL180W becomes essential

• Protein-protein interaction studies: Using techniques like BioID or proximity labeling to identify interaction partners

Each method provides complementary information that, when integrated, can suggest potential functions and guide more targeted experiments to validate these hypotheses.

What computational approaches are most reliable for predicting the structure of YDL180W?

For transmembrane helical proteins like YDL180W that lack close structural homologues, several specialized approaches have demonstrated effectiveness :

• Homology modeling from distant homologues: Using the method described by Chen et al. (2014), which can accurately model TMH protein structures even with sequence identities as low as 15%

• Deep learning approaches: AlphaFold2 and RoseTTAFold have shown promise for membrane protein structure prediction

• Hybrid methods: Combining experimental constraints from cross-linking or mass spectrometry with computational modeling

• Fragment-based modeling: For regions where template structures are unavailable

The method described by Chen et al. demonstrated significant improvements over traditional approaches like MODELLER, MEDELLER, and I-TASSER for transmembrane proteins , making it particularly suitable for YDL180W structural modeling.

How can researchers experimentally validate predicted structural models of YDL180W?

Validation of structural predictions for membrane proteins like YDL180W requires a multi-faceted approach:

• Site-directed mutagenesis: Testing structure-based predictions of important residues for protein folding or function

• Cysteine cross-linking: Introducing cysteine pairs at predicted proximal positions to verify spatial relationships

• Limited proteolysis: Comparing experimental accessibility with computational predictions

• Circular dichroism (CD): Confirming secondary structure content aligns with predictions

• FTIR spectroscopy: Providing additional validation of secondary structure elements

A comprehensive validation approach would compare experimental data with predictions from multiple modeling methods and refine the models accordingly to improve accuracy .

What are the predicted transmembrane domains and structural features of YDL180W based on current modeling techniques?

Based on the amino acid sequence and computational prediction methods, YDL180W is predicted to contain multiple transmembrane helices. The sequence (MVRLNHAASYFMPIFCSTRPHIVILSALFSISLFSLFYASSELLLHQYDD...) contains hydrophobic stretches characteristic of transmembrane segments .

Predicted structural features include:

Advanced modeling techniques as described by Chen et al. could provide more detailed structural information, potentially reaching near-atomic accuracy for the transmembrane regions (averaging 0.8 Å RMSD to native structures in benchmark cases) .

What is known about genetic interactions of YDL180W and how can this information guide functional studies?

YDL180W has a documented negative genetic interaction with SWT1 , indicating that mutations/deletions in both genes cause a more severe fitness defect than would be expected from the individual mutations alone. This suggests potential functional relationships or pathway redundancy.

To leverage this information for functional characterization:

• Pathway analysis: Investigate the known functions of SWT1 (RNA metabolism) to hypothesize potential related roles for YDL180W

• Epistasis analysis: Determine whether YDL180W acts upstream or downstream of SWT1

• Synthetic genetic array (SGA) expansion: Identify additional genetic interactions to map YDL180W into functional networks

• Condition-specific interaction screening: Test genetic interactions under various stress conditions

The negative genetic interaction with SWT1 suggests potential involvement in RNA processing or related cellular functions, providing a starting point for targeted functional investigations .

How can researchers design experiments to identify potential ligands or substrates of YDL180W?

A systematic approach to identifying potential ligands or substrates includes:

• Thermal shift assays: Screen compound libraries for molecules that stabilize YDL180W

• Surface plasmon resonance (SPR): Test direct binding of candidate ligands

• Isothermal titration calorimetry (ITC): Quantify binding thermodynamics for identified candidates

• Comparative metabolomics: Profile metabolites in wild-type vs. YDL180W deletion strains

• Transport assays: If a transporter function is suspected, test substrate translocation using reconstituted proteoliposomes

For membrane proteins with unknown functions like YDL180W, combining unbiased screening approaches with hypothesis-driven testing based on structural features and localization can help identify potential ligands or substrates.

What methods are most effective for studying protein-protein interactions involving YDL180W in its native membrane environment?

Studying protein-protein interactions for membrane proteins presents unique challenges that require specialized techniques:

• Membrane-based yeast two-hybrid: Modified Y2H systems optimized for membrane protein interactions

• Split-ubiquitin assays: Particularly useful for detecting interactions between membrane proteins

• FRET/BRET approaches: For detecting interactions in living cells with minimal disruption

• Proximity labeling: BioID or APEX2 fusions to identify proteins in the vicinity of YDL180W

• Crosslinking mass spectrometry: To capture transient or weak interactions

These methods maintain the membrane context critical for preserving the native conformation of YDL180W, increasing the likelihood of detecting physiologically relevant interactions that might be missed in detergent-solubilized conditions.

How can protein design and engineering approaches be applied to study YDL180W function?

Advanced protein design approaches can provide insights into YDL180W function through:

• Rational mutagenesis: Based on structural models to test functional hypotheses

• Domain swapping: Replacing segments with corresponding regions from characterized homologs

• Minimal functional domain identification: Creating truncation series to identify essential regions

• Sensor development: Engineering YDL180W variants with built-in conformational reporters

The modeling approach described by Chen et al. suggests that even models derived from distant homologues can be accurate enough for rational design applications . Their research demonstrated that redesigned models exhibited native-like interactions similar to those observed when redesigning X-ray structures, suggesting sufficient accuracy for structure-based engineering approaches.

What are the most promising approaches for resolving the high-resolution structure of YDL180W?

Given the challenges of membrane protein structural determination, several complementary approaches should be considered:

• X-ray crystallography: Requiring extensive construct optimization, lipidic cubic phase crystallization, and diffraction quality screening

• Cryo-electron microscopy: Particularly promising for membrane proteins that resist crystallization

• NMR spectroscopy: For flexible regions or smaller domains of YDL180W

• Integrative structural biology: Combining lower-resolution experimental data with computational modeling

The approach outlined by Chen et al. suggests that accurate computational models can guide experimental structure determination by identifying stabilizing mutations or optimal construct boundaries . Their method improved most starting templates in their benchmark to reach near-atomic accuracy predictions in transmembrane helical regions.

How does YDL180W contribute to cellular physiology in yeast, and what are the implications for understanding similar proteins in other organisms?

While YDL180W remains uncharacterized, a comprehensive approach to understanding its physiological role would include:

• Growth phenotyping: Detailed analysis of deletion strains under diverse conditions

• Transcriptional profiling: RNA-seq analysis of deletion/overexpression strains

• Metabolomic profiling: Identifying metabolic changes associated with YDL180W perturbation

• Evolutionary analysis: Examining conservation and co-evolution patterns across species

Understanding YDL180W function in yeast would provide insights into the roles of homologous proteins in other organisms. Transmembrane helical proteins often perform conserved functions across species, including roles in transport, signaling, or maintaining membrane organization. The modeling approach described by Chen et al. could be extended to predict structures of homologues in other organisms once YDL180W's function is better characterized .