Identification of the porcine C-type lectin dectin-1.

Beta-glucans are conserved glucose polymers found in the cell walls of plants, fungi, yeasts and bacteria. They have a backbone of beta-(1-3)-linked glucose units with beta-(1-6)-glucan-linkages. Although a number of receptors are thought to play a role in mediating the biological response to beta-glucans, dectin-1, a C-type lectin, was described as the most important receptor. Dectin-1 belongs to the large family of pattern recognition receptors (PRRs) which recognize conserved pathogen-associated molecular patterns (PAMPs). Here, we report the identification and characterization of dectin-1 in the pig. We identified two major isoforms (GenBank acc. no. FJ386383 and FJ386384), which differ by the presence of a stalk region separating the carbohydrate recognition domain (CRD) from the transmembrane region. Furthermore, a third minor isoform (acc. no. FJ386385) was identified which was a variation of the primary isoform with a deletion in the transmembrane and stalk region. At the nucleotide level, the full length porcine dectin-1 comprises 744bp and is 88% identical to the bovine dectin-1 and 82% identical to the human dectin-1. Messenger RNA transcripts for porcine dectin-1 were detected in the stomach, the small intestine, colon and rectum, the spleen, the mesenterial lymph nodes and the lungs. The transcript was not expressed in the liver, kidneys, the bladder, the heart, the brains and the skin.