Recombinant Human GRSF1 Protein: Properties & Applications

Recombinant Human GRSF1 Protein is a recombinantly expressed form of the G-rich sequence factor 1, an RNA-binding protein critically involved in mitochondrial RNA processing and post-transcriptional gene regulation.

Product Name

Recombinant Human GRSF1 Protein

SKU

rp372288

Protein Family

RNA Recognition Motif (RRM) family / G-rich sequence factor

Primary Function

Mitochondrial RNA processing and post-transcriptional regulation

Biological Source

Human (Homo sapiens)

Application Areas

RNA metabolism research, mitochondrial biology, protein-RNA interaction studies

What Is GRSF1? Biological Background

G-rich Sequence Factor 1 (GRSF1) is a member of the RNA Recognition Motif (RRM) superfamily of RNA-binding proteins. It was originally identified through its ability to bind G-rich sequences within the 5′ untranslated regions (UTRs) of certain mRNAs, facilitating their translation during cellular stress responses such as influenza virus infection.

Subsequent research has established GRSF1 as a predominantly mitochondrially localized protein in somatic cells. Within the mitochondrial matrix, GRSF1 participates in the processing and maturation of mitochondrial RNAs (mtRNAs), including mitochondrial ribosomal RNAs (rRNAs) and mitochondrial transfer RNAs (tRNAs). It cooperates with other components of the mitochondrial RNA processing machinery, such as RNase P, to ensure the accurate cleavage and stabilization of polycistronic mitochondrial transcripts.

GRSF1 has also been implicated in the formation of mitochondrial RNA granules (MRGs), phase-separated condensates in the mitochondrial matrix that are thought to be sites of RNA processing and ribosome assembly. Dysregulation of GRSF1 has been associated with impaired mitochondrial function, oxidative stress, and cellular senescence, making it a protein of significant interest in mitochondrial disease, aging, and cancer biology research.

Protein Structure and Key Functional Domains

Human GRSF1 contains three tandem RNA Recognition Motifs (RRMs), which are the primary structural units responsible for RNA binding. These RRM domains enable GRSF1 to engage with G-rich RNA sequences with specificity and affinity. In addition to the RRM domains, GRSF1 contains a mitochondrial targeting sequence (MTS) at its N-terminus, which directs the protein to the mitochondrial matrix following cytoplasmic translation.

The modular RRM architecture is characteristic of many RNA-binding proteins and allows GRSF1 to participate in diverse RNA-protein and protein-protein interactions within both cytoplasmic and mitochondrial compartments. The ability of GRSF1 to self-associate and interact with other RNA-binding proteins is thought to underlie its role in the formation and organization of mitochondrial RNA granules.

Recombinant production of GRSF1 preserves the key functional domains necessary for downstream biochemical and biophysical assays, including RNA electrophoretic mobility shift assays (EMSA), pull-down experiments, and structural studies.

Research Applications of Recombinant Human GRSF1 Protein

Recombinant Human GRSF1 Protein (rp372288) is a versatile tool for researchers studying RNA metabolism, mitochondrial gene expression, and RNA-binding protein biology. Key application areas include:

• RNA-Binding Studies: GRSF1 can be used in electrophoretic mobility shift assays (EMSA) and filter-binding assays to characterize its interaction with G-rich RNA substrates and to map binding domains or identify competing ligands.
• Protein Interaction Assays: As a component of larger RNA processing complexes, recombinant GRSF1 is suitable for co-immunoprecipitation (co-IP), pull-down assays, and surface plasmon resonance (SPR) to identify and validate protein partners.
• Mitochondrial RNA Processing Research: GRSF1 can serve as a functional component in reconstituted in vitro RNA cleavage or processing assays to dissect the mechanisms of mitochondrial RNA maturation.
• Antibody Validation and Assay Development: Purified recombinant GRSF1 protein serves as a positive control antigen for ELISA development, antibody specificity testing, and Western blot standard preparation.
• Structural Biology: High-purity recombinant protein preparations support crystallography, cryo-EM, or NMR studies aimed at resolving GRSF1 domain architecture or RNA-bound conformations.

Storage, Handling, and Quality Considerations

Proper storage and handling of Recombinant Human GRSF1 Protein are essential to maintain activity and integrity. As with most recombinant proteins, researchers should adhere to the following general best practices:

• Storage Temperature: Store at −80 °C for long-term preservation. Avoid repeated freeze-thaw cycles, which can lead to protein aggregation and loss of activity. For short-term use, aliquoting is recommended.
• Buffer Compatibility: Ensure compatibility of the supplied protein buffer with downstream assay conditions. If buffer exchange is required, use gentle methods such as dialysis or desalting columns.
• Handling: Thaw on ice and briefly centrifuge before use to pellet any aggregates. Pipette gently to minimize shear-induced denaturation.
• Purity and Quality Control: Recombinant proteins from Aladdin Scientific undergo standard quality control procedures. Researchers should verify lot-specific purity (typically assessed by SDS-PAGE) and activity data available in the product datasheet.

Always consult the product-specific datasheet for confirmed storage conditions, buffer composition, purity grade, and recommended working concentrations for your application.

Frequently asked questions

What is the biological function of GRSF1 in human cells?

GRSF1 (G-rich Sequence Factor 1) is an RNA-binding protein that functions primarily in the mitochondrial matrix, where it participates in the processing and maturation of mitochondrial RNAs, including rRNAs and tRNAs. It also plays a role in the formation of mitochondrial RNA granules and has been linked to post-transcriptional regulation of cytoplasmic mRNAs under stress conditions.

What assays is Recombinant Human GRSF1 Protein suitable for?

Recombinant Human GRSF1 Protein (rp372288) is suitable for a range of in vitro assays including RNA electrophoretic mobility shift assays (EMSA), protein pull-down and co-immunoprecipitation experiments, ELISA antigen controls, Western blot standards, surface plasmon resonance (SPR), and structural biology applications such as crystallography or cryo-EM.

How should Recombinant Human GRSF1 Protein be stored to maintain activity?

For long-term storage, keep the protein at −80 °C and avoid repeated freeze-thaw cycles by preparing single-use aliquots. Thaw on ice before use and centrifuge briefly to remove any aggregates. Always refer to the product datasheet for lot-specific storage recommendations and buffer composition.

Is Recombinant Human GRSF1 Protein suitable for use as an antibody validation control?

Yes, purified recombinant GRSF1 protein is commonly used as a positive control antigen for validating anti-GRSF1 antibodies in applications such as ELISA, Western blot, and immunoprecipitation. The defined purity and known identity of the recombinant protein make it a reliable reference material for antibody specificity and sensitivity testing.

What makes GRSF1 relevant to mitochondrial disease and aging research?

GRSF1 is essential for proper mitochondrial RNA processing; its loss or dysfunction impairs mitochondrial gene expression, leading to defects in oxidative phosphorylation, increased oxidative stress, and cellular senescence. These phenotypes connect GRSF1 to the study of mitochondrial diseases, neurodegeneration, and the biology of aging, making it a target of interest for researchers in these fields.

References

1. Antonicka H, Sasarman F, Nishimura T, Paupe V, Shoubridge EA. The mitochondrial RNA-binding protein GRSF1 localizes to RNA granules and is required for posttranscriptional mitochondrial gene expression. Cell Metab. 2013.
2. Jourdain AA, Koppen M, Wydro M, et al. GRSF1 regulates RNA processing in mitochondrial RNA granules. Cell Metab. 2013.
3. Noh JH, Kim KM, Abdelmohsen K, et al. HuR and GRSF1 modulate the nuclear export and mitochondrial localization of the lncRNA RMRP. Genes Dev. 2016.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.