Cathepsin L1 Protein, Human (HEK293, C-His)

Cathepsin L1 protein is a thiol protease that plays a key role in lysosomal protein degradation, affecting cellular functions such as turnover, antigen processing, and bone remodeling. It dissolves cross-linked TG/thyroglobulin, releasing the thyroid hormone thyroxine (T4) in the thyroid follicular cavity. Cathepsin L1 Protein, Human (HEK293, C-His) is the recombinant human-derived Cathepsin L1 protein, expressed by HEK293 , with C-6*His labeled tag. The total length of Cathepsin L1 Protein, Human (HEK293, C-His) is 316 a.a., with molecular weight of ~32.8 kDa.

Cathepsin L1 Protein, a thiol protease, emerges as a crucial player in the comprehensive degradation of proteins within lysosomes, impacting various cellular functions such as general protein turnover, antigen processing, and bone remodeling. Its involvement extends to the solubilization of cross-linked TG/thyroglobulin, facilitating the release of thyroid hormone thyroxine (T4) through limited proteolysis in the thyroid follicle lumen. Furthermore, Cathepsin L1 catalyzes the processing of prohormone proenkephalin into the active enkephalin peptide neurotransmitter within neuroendocrine chromaffin cells' secretory vesicles. In the thymus, it regulates CD4(+) T cell positive selection by generating MHCII-bound peptide ligands and mediates invariant chain processing in cortical thymic epithelial cells. Operating as a major elastin-degrading enzyme at neutral pH, Cathepsin L1 accumulates in the extracellular space of antigen-presenting cells, modulating the degradation of the extracellular matrix during inflammation. Additionally, its secreted form contributes to endostatin generation from COL18A1. Beyond its enzymatic roles, Cathepsin L1 is indispensable for cardiac morphology and function, as well as hair follicle morphogenesis, cycling, and epidermal differentiation. Moreover, it plays a vital role in maximizing steroidogenesis stimulated by TIMP1. In the context of microbial infection, especially in cells lacking TMPRSS2 expression, Cathepsin L1 facilitates the entry of human coronaviruses, such as SARS-CoV and SARS-CoV-2, through a slow acid-activated route by proteolysis of coronavirus spike (S) glycoproteins in lysosomes. This activity underscores its significance in host cell infection by these viruses.

Measured by its ability to cleave the fluorogenic peptide substrate Z-LR-AMC. The specific activity is 121918.4296 pmol/min/µg, as measured under the described conditions.

Human

HEK293

C-6*His

P07711 (T18-V333)

1514

TLTFDHSLEAQWTKWKAMHNRLYGMNEEGWRRAVWEKNMKMIELHNQEYREGKHSFTMAMNAFGDMTSEEFRQVMNGFQNRKPRKGKVFQEPLFYEAPRSVDWREKGYVTPVKNQGQCGSCWAFSATGALEGQMFRKTGRLISLSEQNLVDCSGPQGNEGCNGGLMDYAFQYVQDNGGLDSEESYPYEATEESCKYNPKYSVANDTGFVDIPKQEKALMKAVATVGPISVAIDAGHESFLFYKEGIYFEPDCSSEDMDHGVLVVGYGFESTESDNNKYWLVKNSWGEEWGMGGYVKMAKDRRNHCGIASAASYPTVHHHHHH

Approximately 32.8 kDa

• 
  Greater than 95% as determined by reducing SDS-PAGE.

Lyophilized powder.

Lyophilized from a 0.2 μm filtered solution of 20 mM NaAC, 150 mM NaCl, pH 4.5.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.