Proteins rarely
function in isolation; rather, they engage in complex and dynamic networks of
interactions that orchestrate nearly all cellular processes. These
protein-protein interactions (PPIs) are fundamental to signal transduction,
metabolic pathways, DNA replication and repair, cell cycle control, and
structural organization within the cell. Understanding the intricate web of
PPIs, often referred to as the interactome, is therefore essential for
deciphering the mechanisms underlying cellular function, development, and
disease pathogenesis. Mapping these interactions provides critical insights
into protein function, pathway organization, and the emergent properties of
biological systems.
Historically,
PPIs have been investigated using a variety of biochemical and genetic
techniques. Methods such as co-immunoprecipitation followed by Western blotting
or mass spectrometry, and genetic assays like the yeast two-hybrid (Y2H)
system, have yielded invaluable information about binary interactions and
protein complexes. However, these traditional approaches often possess
limitations. Biochemical methods typically require cell lysis, disrupting the
native cellular environment and potentially leading to the loss of transient or
weak interactions or the formation of post-lysis artifacts. Genetic methods
like Y2H, while performed in vivo,
often rely on the expression of fusion proteins in specific cellular
compartments (e.g., the nucleus) and can be prone to false positives and
negatives, sometimes exacerbated by the overexpression of bait and prey
proteins.
Recognizing these
limitations, significant effort has been invested in developing methods capable
of detecting PPIs directly within living cells, preserving the spatial and
temporal context of the interaction. Techniques such as Förster Resonance
Energy Transfer (FRET), Bioluminescence Resonance Energy Transfer (BRET), and
Fluorescence Cross-Correlation Spectroscopy (FCCS) emerged as powerful tools
for in vivo analysis. Among these,
Bimolecular Fluorescence Complementation (BiFC) has
gained prominence as a relatively straightforward and sensitive method for
visualizing PPIs in their native cellular milieu. The development and
application of in vivo techniques
like BiFC represent a significant advancement,
enabling the study of cellular processes with greater physiological relevance
by minimizing perturbations associated with older methodologies.
The BiFC assay is predicated on the principle that certain
fluorescent proteins can be rationally dissected into two non-fluorescent
fragments. These fragments, when brought into close proximity
by the interaction of proteins fused to them, can spontaneously reconstitute a
functional, fluorescent chromophore. In a typical BiFC
experiment, two proteins of interest, Protein A and Protein B, are genetically
fused to the N-terminal fragment (e.g., VN) and the C-terminal fragment (e.g.,
VC) of a split fluorescent protein, respectively. If Protein A and Protein B
interact within the cell, they bring the VN and VC fragments close enough to
fold together correctly, restoring fluorescence. The intensity and localization
of the resulting fluorescence signal provide evidence for the interaction's
occurrence, strength, and subcellular location. This approach allows for direct
visualization of PPIs in living cells using standard fluorescence microscopy
techniques.
The choice of
fluorescent protein is critical for the sensitivity and reliability of BiFC assays. VENUS, a rapidly
maturing and bright variant of Yellow Fluorescent Protein (YFP), is frequently
employed in BiFC studies. Its favorable photophysical
properties, including enhanced brightness, faster maturation kinetics, and
improved photostability compared to earlier green fluorescent protein (GFP)
variants, make it particularly suitable for detecting PPIs, including those
that may be transient or occur at low abundance. The use of a highly
fluorescent and efficiently folding protein like VENUS maximizes the
signal-to-noise ratio, which is especially important in high-throughput or
genome-wide screening contexts where subtle interactions need to be detected
reliably. The Bioneer library system specifically utilizes split VENUS
fragments, designated VN (N-terminal fragment, residues 1-172) and VC
(C-terminal fragment, residues 155-238), for its BiFC
assays.
Leveraging the
power of BiFC and the genetic tractability of the
budding yeast Saccharomyces cerevisiae,
Bioneer Corporation offers a comprehensive resource for systematic, genome-wide
analysis of PPIs in vivo. This
system, based on split VENUS complementation, provides researchers with
powerful tools for large-scale genetic functional analysis, mapping cellular
interaction networks, and investigating the molecular basis of biological
processes. The development of the VENUS-Fusion Library (VN-fusion and
VC-fusion) involved technology transfers from Seoul National University,
signifying its foundation in academic research and likely rigorous initial
validation.
A key feature of
the Bioneer system is its composition of two distinct, complementary
genome-wide libraries constructed in haploid S. cerevisiae strains of opposite mating types.
1. The S. cerevisiae VN-Fusion Library: Contains strains where the N-terminal fragment of VENUS (VN) is fused to the C-terminus of target yeast proteins. These strains are of the MATa mating type.
2. The S. cerevisiae VC-Fusion Library: Contains strains where the C-terminal fragment of VENUS (VC) is fused to the C-terminus of target yeast protein. These strains are of the MAT mating type.
This
dual-library design is essential for BiFC assays. To
test for an interaction between Protein A and Protein B, a MATa
strain expressing Protein A-VN is mated with a MAT strain expressing Protein
B-VC. The resulting diploid cells co-express both fusion proteins, allowing for
VENUS reconstitution and fluorescence detection if Protein A and Protein B
interact. This strategy elegantly employs fundamental principles of yeast
genetics—specifically, mating type switching and diploid formation—to enable
high-throughput BiFC analysis. The use of opposite
mating types facilitates efficient generation of diploid cells where both
components of the BiFC system are present, while
distinct selectable markers associated with each library allow for robust
selection of these diploids.
The Bioneer
VENUS-Fusion library system offers several advantages for PPI research:
Genome-Wide Coverage: Each library individually covers over 90% of the S. cerevisiae proteome, enabling comprehensive, unbiased screening for interactions.
In Vivo Detection: Interactions are detected within living yeast cells, preserving the native cellular environment and allowing for the study of interactions under various physiological conditions or genetic perturbations.
Systematic Approach: The library format facilitates systematic, high-throughput screening approaches, enabling the construction of large-scale PPI maps and network analysis.
Academic Foundation: The VENUS-Fusion library s origin in academic research suggests a strong scientific basis.
The
commercial availability of such a comprehensive, genome-wide resource
significantly lowers the barrier for researchers to undertake sophisticated PPI
screening projects. Labs that may lack the resources or specialized expertise
to construct such libraries de novo
can leverage this off-the-shelf system, thereby accelerating the pace of
discovery in functional genomics and systems biology.
Table 1: Comparative Overview of Bioneer's
S. cerevisiae VN- and VC-Fusion
Library Sets.
|
Feature |
VN-Fusion Library Set (V-1030VN) |
VC-Fusion Library Set (V-1030VC) |
|
Mating Type |
MATa |
MAT |
|
Fused VENUS Fragment |
VN (N-terminal fragment) |
VC (C-terminal fragment) |
|
Tag Location |
C-terminus of target protein |
C-terminus of target protein |
|
Primary Selection Marker |
KlURA3 (Uracil
prototrophy) |
LEU2 (Leucine
prototrophy) |
|
Number of Strains |
5,809 |
5,552 |
|
Reported Genomic Coverage |
> 90% of S. cerevisiae proteome |
> 90% of S. cerevisiae proteome |
|
Parental Strain Background
Genotype |
MATa his3 1 leu2 0 met15 0 ura3 0 GENE X-VN::KlURA3 |
MAT his3 1
leu2 0 met15 0 ura3 0 GENE X-VC:: LEU2 |
|
Expression Control |
Native promoter of target
gene |
Native promoter of target
gene |
|
Catalog Number |
V-1030VN |
V-1030VC |
Note: The VC library parent strain genotype is inferred
based on the MAT mating type, the LEU2 marker complementing a likely leu2 0
mutation.
The VN-Fusion
library was meticulously constructed to facilitate reliable BiFC
analysis. The N-terminal fragment of the VENUS protein (VN) was systematically
fused to the C-terminus of target proteins across the yeast genome. This
C-terminal tagging strategy is often preferred in large-scale studies as it is
generally less likely to interfere with N-terminal targeting signals or
critical functional domains compared to N-terminal tagging, thus minimizing the
potential for functional disruption of the tagged protein.
The DNA cassettes
encoding the C-terminal VN tag and the selectable marker (KlURA3) were integrated directly into the yeast chromosome at the
endogenous locus of each target gene via homologous recombination. This genomic
integration ensures stable, single-copy expression of the fusion protein,
avoiding the variability in expression levels often associated with
plasmid-based systems. Crucially, the expression of each VN-fusion protein is
driven by the native promoter of the corresponding target gene. Maintaining
physiological expression levels is paramount for the biological relevance of
observed interactions, as artificial overexpression can lead to non-specific
aggregation or interactions that do not occur under normal cellular conditions.
This combination of C-terminal tagging, genomic integration, and native
promoter control reflects a design philosophy aimed at maximizing biological
relevance and minimizing experimental artifacts.
The library
strains were generated in a standard Saccharomyces
cerevisiae laboratory background with a MATa
mating type, facilitating crosses with the complementary MAT VC-fusion
library. The specific documented genotype is MATa his3 1 leu2 0 met15 0 ura3 0 GENE X-VN::KlURA3.
The presence of multiple auxotrophic markers (his3 1, leu2 0, met15 0, ura3 0) is characteristic of widely used
yeast genetic backgrounds, such as BY4741. This standard background ensures
compatibility with a vast array of existing yeast genetic tools and resources,
allowing researchers to readily combine these library strains with other
mutations or introduce plasmids carrying complementary selectable markers for
more complex experimental designs. The KlURA3
marker integrated with the VN tag provides specific selection for the fusion
construct itself.
The library
employs the N-terminal fragment (residues 1-172) of the VENUS fluorescent
protein as the BiFC component fused to the target
proteins.
The VN-Fusion
library set encompasses 5,809 distinct strains. This extensive collection
provides broad representation of the yeast proteome, covering over 90% of
annotated open reading frames (ORFs) in S.
cerevisiae.
Successful
integration of the VN-fusion cassette is selected using the Kluyveromyces lactis URA3 (KlURA3)
gene. This marker confers uracil prototrophy, allowing strains carrying the
integrated cassette to grow on synthetic minimal medium lacking uracil,
provided the parental strain background is ura3 0.
Bioneer provides
flexibility in accessing the VN-Fusion library. The complete collection
(Catalog # V-1030VN) is available as a set of 63 96-well microtiter plates
containing glycerol stocks, suitable for high-throughput screening and
long-term storage. Additionally, researchers can procure individual strains of
interest, supplied either on agar slants (Catalog # V-1010VN-A) for immediate
use or as glycerol stocks (Catalog # V-1010VN-G) for focused studies or
validation experiments. This dual availability caters to diverse research
needs, supporting both large-scale discovery projects and hypothesis-driven
investigations of specific interactions.
The VC-Fusion
library is an indispensable component of the Bioneer BiFC
system. A BiFC assay requires the co-expression of
two putative interaction partners, one fused to the VN fragment and the other
to the VC fragment. Therefore, this library, containing strains expressing
proteins fused to the C-terminal VENUS fragment (VC), is essential for
performing interaction screens in conjunction with the VN-Fusion library.
Similar
to
the VN library, the VC-Fusion library features C-terminal tagging of target
proteins, driven by their native promoters, with the fusion cassettes
integrated into the genome via homologous recombination. An interesting aspect
of the VC library's construction is its origin: it was generated by modifying
strains from the well-established S.
cerevisiae TAP (Tandem Affinity Purification)-tagged collection. In these
strains, the original C-terminal TAP tag and its associated HIS3MX6 marker were precisely replaced
with the VC tag and the LEU2
selectable marker. This approach offers significant advantages. By leveraging
the existing, extensively validated TAP-tagged collection, where gene targeting
and protein expression were likely already confirmed, the construction process
could be streamlined, potentially enhancing the overall quality and reliability
of the resulting VC-Fusion library compared to building it entirely de novo.
Consistent with
the dual-library strategy for BiFC, the VC-Fusion library
strains possess the MAT mating type, enabling efficient mating with the MATa VN-Fusion strains. These VC-Fusion strains were
originally derived from the BY4741 background, and both the mating type switch
to MAT and the replacement of the TAP tag with the VC tag were performed to
ensure compatibility with the MATa VN-Fusion library. The
integration of the LEU2 marker
confers leucine prototrophy to the final VC-fusion strains, complementing the
likely leu2 0 mutation in the parent.
This library
incorporates the C-terminal fragment (residues 155-238) of the VENUS
fluorescent protein fused to the target proteins.
The VC-Fusion
library set consists of 5,552 strains, providing coverage of over 90% of the S. cerevisiae proteome. A slight
discrepancy exists between the size of the VN library (5,809 strains) and the
VC library (5,552 strains). This minor difference could arise from variations
in the success rates of cassette integration and replacement during
construction, differing criteria for strain inclusion in the final sets, or
inherent differences between the starting ORF collections used for each library
(especially given the VC library's origin from the TAP collection). While the
coverage is high for both, researchers planning exhaustive genome-wide screens
should note that for a small fraction of genes, a fusion construct might exist
in only one of the two libraries.
The Saccharomyces cerevisiae LEU2 gene
serves as the selectable marker for the VC-Fusion library. Integration of the
VC-LEU2 cassette allows strains to
grow on synthetic minimal medium lacking leucine, assuming a leu2 0 parental background. The use of LEU2 for the VC library and KlURA3 for the VN library provides two
distinct, complementary markers. This is a critical design feature enabling
robust selection of diploid cells following mating; diploids formed from the
fusion of appropriate ura3 0 and leu2 0 haploid parents will be
prototrophic for both uracil and leucine and can be easily isolated on doubly
selective medium.
Similar
to
the VN library, the VC-Fusion library is offered as a complete set (Catalog #
V-1030VC) comprising 66 96-well plates of glycerol stocks. Individual VC-fusion
strains can also be ordered separately on agar (Catalog # V-1010VC-A) or as
glycerol stocks (Catalog # V-1010VC-G).
The standard
workflow for utilizing the Bioneer VENUS-Fusion libraries begins with selecting
the appropriate strains. To test for an interaction between Protein A and
Protein B, one selects the MATa strain expressing
Protein A-VN and the MAT strain expressing Protein B-VC. These two haploid
strains are then mixed under conditions permissive for mating (conjugation).
This typically involves co-culturing the strains briefly in rich medium or
patching them together on a plate to allow cell fusion and the formation of
diploid zygotes. Subsequently, the cell mixture is plated onto a medium that selects for diploid cells. Given the KlURA3 marker in the VN library and the LEU2 marker in the VC library, plating on synthetic minimal medium
lacking both uracil and leucine (SD -Ura -Leu) effectively selects
for diploids, which should have inherited both markers, while
counter-selecting against unmated haploids (assuming appropriate auxotrophic
backgrounds). The efficiency of this mating and diploid selection process is
crucial for the success of the BiFC assay, and the
library system's design, with distinct mating types and complementary
selectable markers, is optimized to ensure this efficiency.
Standard S. cerevisiae cultivation practices are
employed. Yeast strains are typically grown at 30 C. Rich medium, such as YPD
(Yeast Extract Peptone Dextrose), is used for routine propagation of strains
where selection is not required. For selection purposes (e.g., maintaining
haploid strains carrying the fusion constructs or selecting diploids after
mating), synthetic defined (SD) or synthetic complete (SC) dropout media are
used. These media consist of a nitrogen base, a carbon source (typically
glucose), and specific supplements (amino acids, purines, pyrimidines) tailored
to the required selection. The precise composition of these media is critical
for reproducible results, and established formulations are available (see Table
3). Careful attention to standardized media preparation and growth conditions
is essential for reliable yeast genetics and quantitative BiFC
experiments.
Table 3: Recommended Media Components for Yeast Culture and
BiFC Assays.
|
Medium Type / Component |
Amount per Liter |
Final Concentration |
Notes |
|
SD Medium Base |
|
|
|
|
Bacto-yeast nitrogen base (w/o a.a.) |
6.7 g |
0.67% w/v |
Provides nitrogen source, vitamins,
minerals |
|
Glucose (Dextrose) |
20 g |
2.0% w/v |
Carbon source |
|
Bacto Agar (for solid media) |
20 g |
2.0% w/v |
Solidifying agent |
|
SC Medium Supplements (Examples) |
|
|
Final concentrations (mg/L) per |
|
Adenine sulfate |
20 mg |
20 mg/L |
Add for ade auxotrophs |
|
Uracil |
20 mg |
20 mg/L |
Add for ura auxotrophs |
|
L-Tryptophan |
20 mg |
20 mg/L |
Add for trp auxotrophs |
|
L-Histidine-HCl |
20 mg |
20 mg/L |
Add for his auxotrophs |
|
L-Arginine-HCl |
20 mg |
20 mg/L |
Add for arg auxotrophs |
|
L-Methionine |
20 mg |
20 mg/L |
Add for met auxotrophs |
|
L-Tyrosine |
30 mg |
30 mg/L |
Add for tyr auxotrophs |
|
L-Leucine |
60 mg |
60 mg/L |
Add for leu auxotrophs |
|
L-Isoleucine |
30 mg |
30 mg/L |
Add for ile auxotrophs |
|
L-Lysine-HCl |
30 mg |
30 mg/L |
Add for lys auxotrophs |
|
L-Phenylalanine |
50 mg |
50 mg/L |
Add for phe auxotrophs |
|
L-Glutamic acid |
100 mg |
100 mg/L |
|
|
L-Aspartic acid |
100 mg |
100 mg/L |
|
|
L-Valine |
150 mg |
150 mg/L |
|
|
L-Threonine |
200 mg |
200 mg/L |
|
|
L-Serine |
400 mg |
400 mg/L |
|
|
YPD Medium (Rich Medium) |
|
|
Standard formulation, components per |
|
Yeast Extract |
10 g |
1.0% w/v |
|
|
Peptone |
20 g |
2.0% w/v |
|
|
Glucose (Dextrose) |
20 g |
2.0% w/v |
|
|
Bacto Agar (for solid media) |
20 g |
2.0% w/v |
|
Note: For dropout media (e.g., SD -Ura -Leu), omit the
specific supplements corresponding to the markers being selected for.
Diploid cells
successfully selected after mating are then typically examined for VENUS
fluorescence using standard fluorescence microscopy. The presence of a
fluorescent signal indicates that the VN- and VC-tagged proteins have
interacted, bringing the VENUS fragments together to reconstitute the
fluorophore. The subcellular localization of the signal can also provide
valuable information about where the interaction occurs within the cell.
While the primary
application is often qualitative detection of interactions, BiFC
assays using VENUS can potentially be quantitative. Studies have shown that BiFC signal intensity can correlate with the abundance or
affinity of the interaction, and the assay can be used to measure cell-to-cell
variation in PPIs. However, achieving robust quantification requires careful
experimental design, appropriate controls (e.g., non-interacting protein pairs,
controls for protein expression levels), and sophisticated image acquisition
and analysis protocols. Researchers aiming for quantitative BiFC
using these libraries may need to develop and validate such protocols,
potentially consulting relevant literature, as the library itself is primarily
presented as a tool for interaction discovery.
The most direct
application of the Bioneer VENUS-Fusion library system is the systematic,
large-scale screening for PPIs across the entire S. cerevisiae proteome. By systematically mating arrays of
VN-fusion strains against arrays of VC-fusion strains (or a specific VC-fusion
bait against the entire VN-fusion library array, and vice versa), researchers
can identify novel interactions and construct comprehensive PPI maps. This
unbiased approach is invaluable for discovering previously unknown functional
linkages between proteins.
Identifying the interaction partners of a protein is a powerful strategy for
elucidating its biological function. PPI data generated using these libraries
can place uncharacterized proteins within the context of known cellular
pathways and processes. Mapping the interactions within specific pathways or
complexes can reveal organizational principles, regulatory mechanisms, and
functional modules within the cell's machinery.
A significant
advantage of the in vivo BiFC approach is the ability to study how PPI networks are
remodeled under different conditions. Researchers can use the libraries to
investigate how interactions change in response to environmental stresses,
nutrient availability, drug treatments, or specific genetic backgrounds.
Furthermore, the system can potentially be used to study the influence of
post-translational modifications (PTMs), such as phosphorylation or sumoylation, on interaction dynamics, as demonstrated in
principle for BiFC assays. This capability moves
beyond static interaction maps to probe the dynamic nature and regulation of
the cellular interactome, providing a richer understanding of how cells adapt
and respond to stimuli.
The data
generated using these S. cerevisiae
libraries can serve as a reference point for comparative studies. By comparing
the yeast interactome with those of other organisms (where similar large-scale
data are available), researchers can investigate the conservation and
divergence of protein interaction networks across evolution, shedding light on
fundamental biological principles and species-specific adaptations.
Overall, these
libraries serve as a foundational resource for systems biology. The comprehensive PPI data they enable
contribute directly to the construction and refinement of network models
that aim to capture the integrated behavior of cellular systems.
Ensuring the
quality and reliability of genome-wide resources is paramount for their
successful application. Bioneer employs several measures and provides tools for
the quality control (QC) of its VENUS-Fusion libraries.
The construction
strategy itself incorporates elements of QC. The use of homologous
recombination for genomic integration aims for precise targeting of the fusion
cassettes to the correct endogenous loci. The integration process is coupled
with selection for the integrated markers (KlURA3
or LEU2), providing a primary screen
for successful modification events. Furthermore, the VC-Fusion library's
construction leveraged the pre-existing,
well-characterized TAP-tagged collection, inheriting a degree of validation
from that prior effort.
A key QC feature,
particularly for the VN-Fusion library, is the availability of the AccuOligo
S. cerevisiae VN-fusion Library Validation Primer Set (Catalog # V-1030VN-P).
This set contains 5,809 primers, corresponding to the strains in the VN library
set. It is designed for PCR-based verification of the correct integration of
the VN tag at the C-terminus of each target gene. The primers are provided as a
mixture of target gene-specific primers and a common primer annealing within
the VN module, simplifying PCR setup. The provision of these validation primers
is a significant QC measure, empowering end-users to independently confirm the
integrity of specific strains before or during their experiments. This
transparency allows researchers to verify constructs
and troubleshoot potential issues, thereby increasing confidence in the library
resource. While a similar dedicated validation primer set for the VC-Fusion
library is not explicitly mentioned in the reviewed documentation, comparable
QC procedures during manufacturing or alternative validation strategies would
be expected for a high-quality commercial library. Users may need to inquire
further or design their own checks for VC strains if independent verification
is required.
Bioneer
Corporation holds ISO 9001 Quality Management System certification. While this
is a general certification related to the company's overall quality management
processes and not specific to this product line, it suggests an established
framework for standardized design, development, production, and quality control
procedures are in place across the company, likely
encompassing the manufacturing of these complex biological libraries.
Accessing and
utilizing the Bioneer S. cerevisiae
VENUS-Fusion library system is facilitated by clear ordering procedures,
supporting resources, and customer support channels.
The libraries and
related products can be ordered using specific catalog numbers (see Table 2).
For ordering individual strains (VN or VC fusion), researchers first need to
identify the standard ORF ID (Open Reading Frame Identifier, e.g., YAL001C) for
their gene(s) of interest using resources like the Saccharomyces Genome
Database (SGD) at https://www.yeastgenome.org. The ordering
process requires the completion and submission of a Material Transfer Agreement
(MTA), a standard legal document governing the use of biological materials. A
specific VENUS MTA (Version 2) download link is provided on the product pages.
The completed MTA, along with the list of desired ORF IDs (for individual
strains) or the catalog number for library sets, should be submitted via email
to Bioneer's sales department (sales@bioneer.com).
The requirement for an MTA is standard practice, ensuring clarity on
intellectual property rights and terms of use for these valuable biological
resources.
Table 2: Product and Ordering Information for VENUS-Fusion
Libraries and Related Products.
|
Product Description |
Catalog Number |
Format |
No. of Strains / Primers |
Key Ordering Notes |
|
S. cerevisiae
VN-fusion Library Set |
V-1030VN |
Full Set (63x 96-well
plates), Glycerol |
5,809 strains |
MTA required |
|
S. cerevisiae
VN-fusion Library Individual Strain |
V-1010VN-A |
Individual Strain, Agar |
1 strain |
MTA required, Specify ORF ID
(via SGD) |
|
S. cerevisiae
VN-fusion Library Individual Strain |
V-1010VN-G |
Individual Strain, Glycerol |
1 strain |
MTA required, Specify ORF ID
(via SGD), Dry ice fee |
|
AccuOligo S. cerevisiae VN-fusion Library
Validation Primer Set |
V-1030VN-P |
Primer Set |
5,809 primers |
For QC of VN library |
|
S. cerevisiae
VC-fusion Library Set |
V-1030VC |
Full Set (66x 96-well
plates), Glycerol |
5,552 strains |
MTA required |
|
S. cerevisiae
VC-fusion Library Individual Strain |
V-1010VC-A |
Individual Strain, Agar |
1 strain |
MTA required, Specify ORF ID
(via SGD) |
|
S. cerevisiae
VC-fusion Library Individual Strain |
V-1010VC-G |
Individual Strain, Glycerol |
1 strain |
MTA required, Specify ORF ID
(via SGD), Dry ice fee |
Bioneer offers
two shipping formats for individual strains and library sets:
Agar Type: Strains are provided cultured on rich solid medium (YPD) in 2.0 ml microtubes. These are shipped at ambient temperature, suitable for immediate streaking and use.
Glycerol Type: Strains are provided as liquid cultures in rich medium (YPD) supplemented with 25-30% glycerol in 2.0 ml microtubes. These are shipped frozen on dry ice (incurring an additional fee) and are intended for long-term storage at -70 C or -80 C. Library sets are typically supplied in this format.
Proper
storage according to the format received is essential to maintain strain
viability and library integrity.
To support
researchers using the VENUS-Fusion libraries, Bioneer provides several
resources accessible via their website:
Manuals: A detailed manual for the S. cerevisiae VN-Fusion Library is available.
Material Safety Data Sheets (MSDS): Safety information for the VN-Fusion Library is provided.
Brochures: Informative brochures describing the S. cerevisiae Genome-wide VENUS-Fusion Library & BiFC Vector System are available in both Korean and English. A direct link to the English PDF brochure is provided on the VN library set product page.
These
documents provide valuable technical details, protocols, safety guidelines, and
background information.
For specific
inquiries, Bioneer offers dedicated support channels:
Sales Inquiries: sales@bioneer.com.
Technical Support (VENUS Libraries): gpscreen@bioneer.co.kr.
The
provision of multiple formats, comprehensive documentation, and dedicated
technical support reflects a commitment to facilitating the effective use of
these advanced research tools by the scientific community.
The Bioneer Saccharomyces cerevisiae
Genome-wide VENUS-Fusion Library system represents a sophisticated and powerful
resource for the in vivo
investigation of protein-protein interactions. Comprising complementary MATa VN-fusion and MAT VC-fusion libraries with extensive
genomic coverage (>90%), the system leverages the sensitivity of Bimolecular
Fluorescence Complementation (BiFC) with the genetic
advantages of yeast. Key strengths include the C-terminal tagging strategy,
expression driven by native promoters to maintain physiological relevance,
stable genomic integration of fusion constructs, and a design intrinsically
linked to classical yeast genetics for efficient mating and diploid selection.
Supported by validation tools and comprehensive documentation, this system
provides a robust platform for both large-scale interactome mapping and focused
studies of specific PPIs.
This resource
significantly facilitates the exploration of the yeast interactome, enabling
the discovery of novel interactions and the detailed mapping of cellular
networks. Its in
vivo nature allows researchers to move beyond static interaction maps
towards understanding the dynamics and regulation of PPIs in response to
cellular signals, environmental changes, and genetic context. The data
generated using these libraries contribute substantially to systems biology
initiatives, providing essential components for constructing and refining
computational models of cellular processes. The commercial availability of such
a well-engineered, genome-wide tool democratizes access to advanced PPI
analysis, accelerating research in functional genomics, cell biology, and drug
discovery.
While the
VENUS-Fusion library system is a powerful tool, users should employ rigorous
experimental design, including appropriate positive and negative controls, to
validate findings, as BiFC assays can sometimes yield
artifacts or miss certain classes of interactions. The libraries provide a
foundational snapshot of potential interactions under standard laboratory
conditions; exploring the full dynamics of the interactome across diverse cellular
states and conditions remains a key challenge that these libraries help
initiate. Nonetheless, the Bioneer S.
cerevisiae VENUS-Fusion library system stands as a mature, well-conceived
application of BiFC technology, poised to continue
driving significant advances in our understanding of the complex molecular
interactions that underpin life.