Recombinant Human MED13L Protein: Properties & Research Uses

Recombinant Human MED13L Protein is a recombinant form of the human Mediator complex subunit 13-like protein, produced to support mechanistic studies of transcriptional regulation and gene expression research.

Protein Name

Mediator Complex Subunit 13-Like (MED13L)

Product SKU

rp376631

Species Origin

Human (Homo sapiens)

Protein Type

Recombinant protein

Primary Function

Subunit of the Mediator transcriptional coactivator complex; involved in RNA polymerase II-dependent gene transcription

Associated Pathology

MED13L mutations are linked to MED13L syndrome, characterised by intellectual disability and facial dysmorphia

Biological Background of MED13L

MED13L (Mediator Complex Subunit 13-Like) is a large nuclear protein that functions as a component of the Mediator complex, a multi-subunit transcriptional coactivator that bridges gene-specific transcription factors with the general RNA polymerase II (Pol II) machinery. The Mediator complex plays a central role in the regulation of nearly all Pol II-dependent genes in eukaryotic cells, acting as a signal-integrating hub that relays regulatory information from enhancers to the core promoter.

MED13L shares structural homology with MED13 and together they represent closely related paralogues within the kinase module (CKM or CDK8 module) of the Mediator complex. The CDK8 module, comprising CDK8, Cyclin C, MED12 and MED13 (or MED13L), can reversibly associate with the Mediator core and modulates transcriptional activity in a context-dependent manner—acting as either a coactivator or a repressor depending on the promoter and cellular context.

Mutations in the MED13L gene have been identified as the causative basis of MED13L syndrome (also referred to as mental retardation and distinctive facial features with or without cardiac defects, MRFACD), an autosomal dominant neurodevelopmental disorder characterised by moderate-to-severe intellectual disability, hypotonia, speech impairment, and characteristic craniofacial features. This clinical relevance makes MED13L a subject of active research in developmental biology and rare disease genomics.

Recombinant Protein Production and Biochemical Properties

Recombinant Human MED13L Protein (SKU: rp376631) is produced using recombinant DNA technology to yield a defined, reproducible protein preparation suitable for in vitro research applications. Recombinant expression platforms—such as mammalian, insect (baculovirus), or bacterial cell systems—are commonly employed for large nuclear scaffold proteins, with the choice of expression host influencing protein folding, post-translational modifications, and functional activity.

As a high-molecular-weight nuclear protein, MED13L presents challenges for recombinant production, including solubility and correct folding. Recombinant preparations are typically provided with an affinity tag (e.g., His-tag, GST-tag, or FLAG-tag) to facilitate purification by affinity chromatography, followed by additional chromatographic steps to achieve the required purity. Researchers should consult the product datasheet for lot-specific information regarding expression host, tag configuration, formulation buffer, purity grade, and recommended storage conditions.

Quality control for recombinant MED13L typically includes SDS-PAGE analysis to confirm molecular weight and purity, Western blot verification using anti-MED13L antibodies, and endotoxin testing for preparations intended for cell-based assays. Functional activity may be assessed through protein-protein interaction assays with other Mediator subunits or CDK8 module components.

Research Applications

Recombinant Human MED13L Protein supports a broad range of biochemical and cell biology research applications centred on transcriptional regulation and Mediator complex biology:

• Protein–Protein Interaction Studies: MED13L recombinant protein can be used in co-immunoprecipitation (Co-IP), pull-down assays, and surface plasmon resonance (SPR) experiments to characterise interactions between MED13L and other Mediator subunits, CDK8, Cyclin C, or transcription factors.
• Antibody Validation: Recombinant MED13L serves as a positive control antigen for validating anti-MED13L antibodies in Western blot, ELISA, and immunoprecipitation assays.
• Structural Biology: Purified recombinant protein or defined domains/fragments can be used in X-ray crystallography, cryo-electron microscopy (cryo-EM), or NMR studies to elucidate MED13L structure and its mode of interaction within the CDK8 module.
• Disease Mechanism Research: Recombinant MED13L facilitates studies into the molecular consequences of MED13L syndrome-associated mutations by enabling comparison of wild-type and mutant protein behaviour in biochemical assays.
• Drug Discovery: As a component of a therapeutically relevant complex, MED13L recombinant protein may be used in compound screening assays targeting the CDK8 module, which has gained interest as a potential oncology and rare disease drug target.

Handling, Storage, and Quality Considerations

To maintain the integrity and activity of Recombinant Human MED13L Protein, researchers should adhere to the following general best practices, while always consulting the product-specific datasheet for authoritative guidance:

• Storage: Recombinant proteins are generally stored at –80 °C for long-term stability. Avoid repeated freeze–thaw cycles, which can lead to protein aggregation and loss of activity. Aliquoting upon receipt is strongly recommended.
• Reconstitution: If supplied lyophilised, reconstitute gently in the buffer recommended in the datasheet. Allow the vial to equilibrate to room temperature before opening and mix by gentle pipetting rather than vortexing.
• Working Concentration: Determine the optimal working concentration empirically for each application. Pilot experiments using a concentration range are advised before committing to large-scale assays.
• Handling: Work on ice where possible to minimise protein degradation. Use low-binding tubes and tips to minimise adsorption losses, particularly when working with dilute protein solutions.
• Quality Verification: Upon receipt, verify protein integrity by SDS-PAGE or Western blot before proceeding to functional assays. Document lot numbers for reproducibility and regulatory compliance purposes.

Frequently asked questions

What is MED13L and why is it important in transcription research?

MED13L is a subunit of the Mediator complex's CDK8 kinase module, which regulates RNA polymerase II-dependent transcription across a wide range of genes. It is important because it modulates transcriptional output in response to signalling cues and because mutations in MED13L cause a clinically recognised neurodevelopmental syndrome, making it relevant to both basic and translational research.

What applications is Recombinant Human MED13L Protein (rp376631) suitable for?

Recombinant Human MED13L Protein is suitable for protein–protein interaction studies, antibody validation (Western blot, ELISA), structural biology investigations, disease mechanism research related to MED13L syndrome, and compound screening in drug discovery programmes targeting the CDK8 module. Always verify suitability for your specific application against the product datasheet.

How should Recombinant Human MED13L Protein be stored to preserve activity?

In general, recombinant proteins should be stored at –80 °C for long-term stability, with repeated freeze–thaw cycles avoided by preparing single-use aliquots upon receipt. The specific formulation buffer, storage temperature, and shelf-life for rp376631 are detailed in the product datasheet, which should be consulted for authoritative guidance.

Is MED13L related to any human disease?

Yes. Heterozygous loss-of-function and missense mutations in the MED13L gene are the genetic basis of MED13L syndrome, an autosomal dominant neurodevelopmental disorder characterised by intellectual disability, hypotonia, impaired speech, and distinctive facial features, sometimes accompanied by congenital heart defects. Research into recombinant MED13L protein helps elucidate the molecular mechanisms underlying this condition.

How does MED13L differ from MED13?

MED13L and MED13 are paralogous proteins encoded by distinct genes that share significant sequence and structural homology. Both are components of the CDK8 kinase module of the Mediator complex, but they appear to be incorporated into the module in a mutually exclusive manner in different cellular or developmental contexts. Their precise functional differences and tissue-specific roles remain an active area of research.

References

1. Spaeth JM et al. The Mediator complex and its CDK module in transcription regulation. J Biol Chem. 2011. [General review of Mediator complex biology—specific details to be verified against primary literature]
2. van Haelst MM et al. Further delineation of the MED13L syndrome. Eur J Hum Genet. 2015. [Clinical description of MED13L syndrome—verify authorship, volume, pages and PMID]
3. Krivtsov AV, Armstrong SA. CDK8 kinase module as a drug target. [Placeholder—verify primary reference for CDK8 module in drug discovery context]

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