Recombinant Human Epididymal-specific lipocalin-8 (LCN8)
Description
Physiological Functions
LCN8 plays essential roles in male fertility and epididymal function:
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Sperm Maturation: Binds and transports retinoids (e.g., all-trans retinoic acid) within the epididymal lumen, facilitating sperm maturation .
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Epithelial Differentiation: Mouse studies show Lcn8 downregulation disrupts epididymal epithelial structure, leading to dedifferentiation and impaired fertility .
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Ligand Protection: Shields hydrophobic molecules from degradation during transport in reproductive fluids .
Research Findings
Key insights from experimental models:
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Mouse Knockout Models: Conditional ablation of Dicer1 in the epididymis caused reduced Lcn8 expression, resulting in epithelial regression resembling prepubertal states. This correlated with diminished sperm functionality .
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Structural Insights: The β-barrel architecture allows LCN8 to bind diverse ligands, suggesting utility in drug delivery systems .
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Clinical Biomarker Potential: Lipocalins like LCN2 are used diagnostically; recombinant LCN8 could similarly serve in male infertility assays .
Challenges and Future Directions
Current gaps include:
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Mechanistic details of LCN8’s interaction with retinoid signaling pathways.
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In vivo efficacy of recombinant LCN8 in restoring fertility in knockout models.
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Structural optimization for enhanced ligand-binding specificity in biotechnological applications.
Product Specs
Target Background
Q&A
FAQs for Researchers on Recombinant Human Epididymal-Specific Lipocalin-8 (LCN8)
What experimental systems are optimal for studying recombinant LCN8's biological roles?
Recombinant LCN8 produced in HEK 293 cells (>90% purity, <1 EU/µg endotoxin ) is suitable for in vitro assays investigating retinoid transport or sperm maturation. For functional studies:
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Use epididymal epithelial cell lines or organoids to model physiological interactions .
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Pair with knockout models (e.g., Dicer1 fl/fl; Defb41iCre/wt mice) to assess downstream gene regulation (e.g., Cst8, Lcn8 downregulation post-21 days postpartum ).
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Validate protein activity via SDS-PAGE (see for purity standards) and ligand-binding assays (e.g., fluorescence-based retinoid uptake ).
How does recombinant LCN8 compare to endogenous LCN8 in structural and functional properties?
How to resolve contradictions in LCN8-associated gene expression data?
In Dicer1 ablation models, Lcn8 and Cst8 expression declines postnatally, but Ros1 remains unaffected . To investigate:
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Perform time-course qRT-PCR (e.g., days 16–21 postpartum ) to track expression dynamics.
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Use chromatin immunoprecipitation (ChIP) to assess epigenetic regulators near Lcn8 vs. Ros1 loci.
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Test if LCN8 knockdown alters Ros1 stability via RNA-Seq and ribosome profiling.
What methodological strategies address LCN8’s dual role in retinoid transport and sperm maturation?
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Retinoid Transport: Use fluorescence polarization assays with all-trans retinoic acid .
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Sperm Maturation: Co-culture recombinant LCN8 with spermatozoa in vitro and measure motility (CASA) or capacitation markers (e.g., tyrosine phosphorylation ).
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Structural Analysis: Solve the crystal structure of recombinant LCN8 (amino acid sequence: M E E L D R Q K I G G F W R E V G V A S D Q S L V L T A P K R... ) to identify retinoid-binding pockets.
How to design studies probing LCN8’s interaction with other lipocalins in the epididymis?
What controls are critical when using recombinant LCN8 in fertility studies?
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Negative Controls: Heat-denatured LCN8 or His-tagged irrelevant proteins (e.g., BSA-His).
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Positive Controls: Epididymal fluid from wild-type mice (contains endogenous LCN8 ).
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Endpoint Metrics: Quantify sperm count, morphology (e.g., acrosome integrity), and fertilization rates in vitro.
How to reconcile discrepancies between LCN8’s in vitro and in vivo effects?
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If recombinant LCN8 rescues sperm maturation defects in vitro but not in vivo:
