Recombinant Schizosaccharomyces pombe Uncharacterized protein C1795.12c (SPCC1795.12c)

What is currently known about SPCC1795.12c in Schizosaccharomyces pombe?

SPCC1795.12c is classified as an uncharacterized protein in the fission yeast Schizosaccharomyces pombe with a full length of 112 amino acids. According to available databases, it has not yet been associated with specific biological pathways, functions, or protein interactions . This protein represents an opportunity for novel discovery using modern molecular biology techniques. While its small size suggests it may function as part of a larger complex or have a regulatory role, its specific cellular functions remain to be elucidated through experimental approaches.

What are the optimal conditions for expression and purification of recombinant SPCC1795.12c?

Recombinant SPCC1795.12c can be expressed using E. coli expression systems with a histidine tag for purification, as indicated by commercially available preparations . For optimal expression, consider the following protocol:

• Clone the SPCC1795.12c coding sequence into an expression vector with a histidine tag

• Transform the construct into an E. coli expression strain (e.g., BL21(DE3))

• Induce protein expression at optimal temperature (typically 16-30°C)

• Lyse cells using appropriate buffer systems that maintain protein stability

• Purify using nickel affinity chromatography followed by size exclusion chromatography

For S. pombe proteins, codon optimization may significantly improve expression yields in E. coli systems. After purification, verify protein identity through mass spectrometry and Western blotting with anti-histidine antibodies.

How can I design initial characterization experiments for SPCC1795.12c?

Initial characterization should employ a multi-faceted approach:

• Bioinformatic analysis to identify conserved domains and potential homologs

• Subcellular localization studies using fluorescent protein tags or immunofluorescence

• Gene deletion studies to observe phenotypic effects in various growth conditions

• Protein interaction studies using techniques such as yeast two-hybrid or affinity purification coupled with mass spectrometry

• Gene expression analysis across different growth conditions and cell cycle stages

Given SPCC1795.12c's small size (112 amino acids) , consider whether C-terminal or N-terminal tagging would be less likely to disrupt function. When analyzing deletion phenotypes, examine cells microscopically using differential interference contrast and fluorescence microscopy to detect subtle morphological changes .

How can ChIP-seq methodology be applied to investigate potential DNA-binding properties of SPCC1795.12c?

While there is no current evidence that SPCC1795.12c functions as a transcription factor, ChIP-seq could determine if it interacts with chromatin:

• Generate strains expressing epitope-tagged SPCC1795.12c under its native promoter

• Perform chromatin immunoprecipitation following established S. pombe protocols

• Prepare and sequence immunoprecipitated DNA fragments

• Analyze data using peak calling algorithms, retaining peaks with at least 1.75-fold enrichment in at least two samples

• Perform motif discovery analysis to identify potential DNA binding sequences

If SPCC1795.12c binds specific DNA sequences, consider complementary approaches such as 6-mer enrichment analysis, which has successfully identified binding preferences for other S. pombe proteins . Compare identified motifs with known transcription factor binding sites to place findings in context.

What strategies can identify potential binding partners and functional networks for SPCC1795.12c?

To comprehensively map the interactome of SPCC1795.12c:

• Perform affinity purification of tagged SPCC1795.12c followed by mass spectrometry

• Conduct yeast two-hybrid screening against an S. pombe genomic library

• Implement genetic interaction screens by crossing SPCC1795.12c deletion strains with deletion libraries

• Use Yeast Augmented Network Analysis (YANA) to examine conserved genetic interactions

For genetic interaction screens, results can be quantified using software like ScreenMill to identify statistically significant growth defects (synthetic lethal) or growth enhancement (synthetic suppressor) . The pattern of genetic interactions often reveals the biological process in which an uncharacterized protein functions.

The table below summarizes different interaction analysis approaches:

How can temperature sensitivity assays be used to investigate SPCC1795.12c function?

Temperature sensitivity assays can reveal potential roles in essential cellular processes:

• Generate temperature-sensitive alleles through random or site-directed mutagenesis

• Transform constructs into an SPCC1795.12c deletion background

• Test growth at permissive (25°C) and restrictive temperatures (35.5-36.5°C)

• Incorporate phloxin B into media, which stains dead cells for easy visualization

• Analyze cellular phenotypes microscopically at the restrictive temperature

For viable temperature-sensitive mutants, calculate generation times using the equation: T = log(2)/(log(y/x)/(t2-t1)), where T is generation time, y is cells/ml at time t2, and x is cells/ml at time t1 . This approach can reveal if SPCC1795.12c is involved in essential processes such as cell division or morphogenesis.

What transcriptomic approaches would be most informative for understanding SPCC1795.12c regulation?

To characterize the expression and regulation of SPCC1795.12c:

• Perform RNA-seq comparing wild-type strains to SPCC1795.12c deletion mutants

• Conduct time-course experiments during cell cycle progression and stress responses

• Analyze promoter elements to identify potential regulatory motifs

• Integrate findings with existing periodic gene expression data to determine if SPCC1795.12c shows cell cycle-regulated expression

When preparing RNA from S. pombe, typical protocols yield approximately 100μg from standard cultures, with 10μg needed for each Northern blot analysis . For investigating cell cycle-regulated expression, synchronize cultures using methods like centrifugal elutriation or block-and-release with temperature-sensitive mutants .

How can I determine if SPCC1795.12c has a regulatory role in gene expression?

To investigate potential regulatory functions:

• Perform RNA-seq comparing transcriptomes of wild-type and SPCC1795.12c deletion strains

• If nuclear localization is observed, conduct ChIP-seq following protocols similar to comprehensive S. pombe transcription factor studies

• Examine genetic interactions with known transcriptional regulators such as MBF, ace2p, or sep1p

• If ChIP-seq data suggests DNA association, identify potential binding motifs through techniques like 6-mer enrichment analysis

Analyze the distribution of any binding sites relative to transcriptional start sites and correlate with gene expression data. For proteins without classical DNA-binding domains, consider roles in chromatin remodeling or as transcription cofactors.

How can CRISPR-Cas9 genome editing be optimized for functional studies of SPCC1795.12c?

For precise genetic manipulation of SPCC1795.12c:

• Design guide RNAs with minimal off-target effects using S. pombe-specific prediction tools

• Prepare repair templates containing homology arms flanking the target site

• Optimize transformation protocols specifically for S. pombe

• Screen transformants using PCR, restriction digestion, or sequencing

• Verify modified strains for expression or deletion as appropriate

For tagging SPCC1795.12c, consider its small size (112 amino acids) and use compact epitope tags or fluorescent proteins with flexible linkers to minimize functional disruption. Transformation efficiency can be improved by synchronizing cells and performing transformations during S phase.

How can auxotrophic markers be utilized in genetic manipulation studies of SPCC1795.12c?

Auxotrophic markers provide powerful selection tools for genetic studies:

• Select appropriate markers (adenine, glutamic acid, histidine, leucine, lysine, or uracil) based on strain background

• Design gene deletion or tagging constructs with the selected marker flanked by SPCC1795.12c homology regions

• Transform constructs into auxotrophic S. pombe strains

• Select transformants on minimal media lacking the nutrient corresponding to the marker

• Confirm correct integration by PCR or sequencing

Typical supplement concentrations are 225mg/L, though 75mg/L is sufficient except for leucine auxotrophs, which require higher concentrations for optimal growth . Testing for auxotrophy requires replica plating single colonies from YES media to minimal media with and without the appropriate supplement .

What approaches can determine post-translational modifications of SPCC1795.12c?

To investigate post-translational modifications (PTMs):

• Perform mass spectrometry analysis of purified SPCC1795.12c to identify modifications

• Conduct Western blotting with modification-specific antibodies

• Compare PTM profiles under different cellular conditions (e.g., cell cycle stages, stress responses)

• Create mutant versions where predicted modification sites are altered

• Assess the functional impact of these mutations through phenotypic analysis

For small proteins like SPCC1795.12c (112 amino acids) , even a single PTM could significantly impact function. Analysis under different conditions is crucial as PTMs are often dynamically regulated.

How can microscopy techniques be optimized for studying SPCC1795.12c localization?

For optimal visualization of SPCC1795.12c:

• Generate C- or N-terminal fluorescent protein fusions under native promoter control

• Use confocal or spinning disk microscopy for high-resolution imaging

• Implement time-lapse microscopy to track protein dynamics during the cell cycle

• Employ photobleaching techniques (FRAP) to measure protein mobility

• Perform co-localization studies with known cellular markers

For S. pombe specifically, consider the rod-shaped morphology, potential autofluorescence, and optimal growth conditions (29-32°C for wild-type strains) . Differential interference contrast (DIC) microscopy can provide complementary information about cell morphology and division stages .

What structural biology approaches can characterize SPCC1795.12c?

Multiple complementary techniques can reveal structural insights:

NMR spectroscopy would be particularly advantageous for this small protein, potentially revealing dynamic properties and interaction surfaces. Structural studies should be complemented by biochemical assays to validate functions suggested by the structure.

What methods are effective for analyzing evolutionary conservation of SPCC1795.12c?

Evolutionary analysis provides crucial functional insights:

• Perform BLAST searches against diverse fungal and eukaryotic genomes

• Create multiple sequence alignments of identified homologs

• Construct phylogenetic trees using maximum likelihood methods

• Analyze selection pressure using dN/dS ratios to identify conserved functional domains

• Integrate orthology data from specialized databases like PomBase, OrthoMCL, InParanoid8, and Homologene

For uncharacterized proteins, identifying even distant homologs with known functions can provide crucial functional hints. Analysis of synteny (conservation of genomic context) across species can reveal functional relationships that sequence comparison alone might miss.

How can genetic interaction screens be designed to elucidate SPCC1795.12c function?

For comprehensive functional characterization:

• Create a query strain with SPCC1795.12c deleted or conditionally expressed

• Systematically cross this strain with an ordered array of deletion strains

• Analyze resulting double mutants for synthetic lethality (SL) or synthetic suppression (SS)

• Quantify colony sizes using software like ScreenMill

• Normalize data and identify statistically significant interactions (P≤0.05)

Results can be organized into interaction networks to identify functional relationships. The table below shows an example format for organizing significant genetic interactions:

This approach is particularly valuable for uncharacterized proteins, as the pattern of genetic interactions often reveals the biological process in which the protein functions .

What bioinformatic approaches can predict structure and function of SPCC1795.12c?

Modern bioinformatic prediction should include:

• Sequence-based analysis using tools like InterProScan, SignalP, and TMHMM

• Structure prediction using AlphaFold2 or RoseTTAFold

• Function prediction using tools that integrate structural information

• Protein-protein interaction prediction using interface prediction algorithms

• Gene neighborhood analysis to identify functionally related genes

For small proteins like SPCC1795.12c (112 amino acids) , complete structure prediction is now feasible with high confidence. Analysis of predicted binding surfaces and electrostatic properties can suggest potential molecular functions that can guide experimental design.