Background: LCA5 Gene and Lebercilin Biology

The LCA5 gene encodes lebercilin, a ciliary protein that localizes to the transition zone of photoreceptor connecting cilia and to the axoneme of primary cilia in multiple cell types. Lebercilin functions as a scaffold within the ciliary transition zone, facilitating intraflagellar transport (IFT) and maintaining the structural integrity of the photoreceptor outer segment.

Loss-of-function mutations in LCA5 are associated with Leber Congenital Amaurosis type 5 (LCA5), an autosomal recessive retinal dystrophy characterized by severe visual impairment from birth or early infancy. LCA5 belongs to a broader group of ciliopathies—diseases caused by dysfunction of cilia—and studying the lebercilin protein provides mechanistic insights applicable to multiple ciliopathy models.

Recombinant Human LCA5 Protein enables researchers to investigate lebercilin's protein–protein interactions, map functional domains, and develop or validate assays relevant to photoreceptor biology and ciliopathy research.

Reconstitution and Storage Protocol

Reconstitution: Prior to use, briefly centrifuge the vial to collect the lyophilized powder at the bottom. Reconstitute the protein in sterile, ultrapure water or an appropriate buffer (e.g., PBS, pH 7.4) to a concentration recommended on the Certificate of Analysis (CoA). Mix gently by pipetting; do not vortex, as this may denature the protein.

Working Aliquots: After reconstitution, prepare single-use aliquots to minimize freeze-thaw cycles, which can significantly reduce protein activity and increase aggregation. Repeated freeze-thaw cycles (more than 2–3) are not recommended.

Storage Conditions:

• Lyophilized form: Store at –20 °C or –80 °C, protected from moisture and light.
• Reconstituted protein: Store working aliquots at –80 °C for long-term use, or at 4 °C for short-term use (up to 1 week). Addition of a carrier protein (e.g., 0.1% BSA) may help stabilize dilute solutions.

Note: Specific concentration, purity, and buffer recommendations should always be confirmed against the product-specific Certificate of Analysis supplied with each lot.

Experimental Applications and Usage Guidelines

Recombinant Human LCA5 Protein is suitable for a range of biochemical and cell biological applications:

• Protein–Protein Interaction Studies: Use in pull-down assays or co-immunoprecipitation to identify lebercilin-interacting partners within the ciliary proteome.
• Western Blot (WB): Serve as a positive control for anti-LCA5 antibody validation or for establishing standard curves.
• ELISA: Use as a coating or detection antigen to develop or validate immunoassays for lebercilin quantification.
• Structural and Domain Studies: Employ in biophysical assays (e.g., SEC, native PAGE) to study oligomeric state, stability, or domain interactions.
• In Vitro Functional Assays: Reconstitute ciliary transport systems in vitro to examine LCA5's role in IFT complex assembly.

Always titrate the protein for each specific assay system. Confirm biological activity requirements against your experimental endpoint and the product CoA before designing experiments.

Quality, Purity, and Safety Considerations

Purity: Recombinant proteins are typically verified by SDS-PAGE and/or HPLC for purity. Refer to the Certificate of Analysis for lot-specific purity data. High purity minimizes background in sensitive assays such as ELISA and protein interaction studies.

Endotoxin: For cell-based assays or any application involving live cells, confirm that endotoxin levels are within acceptable limits (typically <1.0 EU/µg) as stated in the CoA. Endotoxin contamination can confound downstream biological readouts.

Identity Verification: Protein identity should be confirmed by mass spectrometry or N-terminal sequencing as noted in product documentation.

Safety: Handle in accordance with standard laboratory safety guidelines. Although this protein is not classified as a biohazard, always wear appropriate PPE (gloves, lab coat, eye protection) when handling reagents. Consult the Safety Data Sheet (SDS) before use.

Lot-to-Lot Consistency: When running longitudinal studies, record the lot number and verify comparability across lots using orthogonal methods if assay sensitivity demands it.