• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its binding ability in a functional ELISA. Immobilized rhCL-P1 at 5 µg/mL (100 µL/well) can bind biotinylated advance glycation endproducts of bovine serum albumin (AGE-BSA) with a linear range of    
  3-200 ng/mL.

• Source

  Mouse myeloma cell line, NS0-derived Leu57-Leu742, with an N-terminal 9-His tag

• Accession #

• N-terminal Sequence    
  Analysis

  His

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  76 kDa (monomer)

• SDS-PAGE

  125-130 kDa, reducing conditions

Background: CL-P1/COLEC12

Collectins are a family of Ca⁺⁺-dependent, C-type lectins that contain a collagenous domain and function as recognition molecules for molecular patterns found on pathogens (1 - 4). Human collectin placenta 1 (CL-P1; also known as collectin sub-family member 12 and SRCL type I [scavenger receptor with C-type lectin type I]) is a 110 kDa member of the collectin family of glycoproteins (5, 6). With two exceptions, all collectins are secreted. CL-P1 is the only collectin known to be membrane bound, while CL-L1 (collectin liver-1) is the only known cytoplasmic collectin (1). Human CL-P1 is synthesized as a 742 amino acid (aa) type II transmembrane glycoprotein that contains an N-terminal 39 aa cytoplasmic domain, a 17 aa transmembrane segment, and a 686 aa C-terminal extracellular region (6). The short cytoplasmic domain contains an internalization motif (Y-K-R-F) while the extracellular region is complex, demonstrating a coiled-coil segment, a Ser-Thr rich region, a collagen-like structure and a C-type lectin/ carbohydrate recognition domain (CRD). Notably, this CRD recognizes galactose (and fucose) within the context of asialo-orosomucoids associated with the Lewis^x epitope (7, 8). CL-P1 has a 300 kDa trimeric form due to its collagen-like and coiled-coil helical domains (1, 5). There is a 97 kDa, alternate splice form of CL-P1 (SRCL type II) that shows a 120 aa truncation at the C-terminus. This effectively removes the entire CRD found on full-length CL-P1 (6). Human CL-P1 is 93% aa identical to mouse CL-P1 over the entire extracellular region, and 87% aa identical within each species CRD (5, 9). Human CL-P1 is known to be expressed in vascular endothelial cells (5). CL-P1 may play a role in bacterial recognition or as a scavenger receptor for desialylated.

• References:

1. van de Wetering, JK. et al. (2004) Eur. J. Biochem. 271:1229.

2. Holmskov, U. et al. (2003) Annu. Rev. Immunol. 21:547.

3. Hoppe, H-J. and K. Reid (1994) Protein Sci. 3:1143.

4. Hickling, T.P. et al. (2004) J. Leukoc. Biol. 75:27.

5. Ohtani, K. et al. (2001) J. Biol. Chem. 276:44222.

6. Nakamura,K. et al. (2001) Biochem. Biophys. Res. Commun. 280:1028.

7. Coombs, P.J. et al. (2005) J. Biol. Chem. 280:22993.

8. Yoshida, T. et al. (2003) J. Biochem. 133:271.

9. Nakamura, K. et al. (2001) Biochim. Biophys. Acta 1522:53.

• Long Name:

  Collectin Placenta 1

• Entrez Gene IDs:

  81035 (Human); 140792 (Mouse); 361289 (Rat)

• Alternate Names:

  CL-P1; CLP1, cleavage and polyadenylation factor I subunit, homolog (S. cerevisiae); COLEC12; EC 2.7.1.78; hClp1; HEABATP/GTP-binding protein; homolog of yeast CFIA subunit Clp1p; NSR2; Polynucleotide kinase Clp1; polyribonucleotide 5'-hydroxyl-kinase Clp1; Pre-mRNA cleavage complex II protein Clp1; SCARA4; SRCL Type I