Molecular cloning of the canine CD44 antigen cDNA.

Molecular cloning of the dog homologue of the human CD44 was achieved using RT/PCR. A 1055 bp cDNA has a deduced amino acid sequence of 351 residues, 338 of them correspond to the mature protein. Nine conserved cysteine residues were found. The extracellular region contains a single link superfamily domain on the N-terminal part and potential post-translational modification sites as: N- and O-linked glycosylation sites and chondroitin sulfate attachment sites. Three mRNAs of 2.2, 3.8 and 4.4 kb were identified on Northern blot analysis and Western blot hybridization revealed a 85-90 kDa protein expressed in lymph node tissue.