Molecular cloning and expression of the cDNA encoding feline granulocyte colony-stimulating factor

Both genomic DNA and cDNA of the feline granulocyte colony-stimulating fact or (G-CSF) gene were cloned from CRFK cells. Southern blot analysis showed that the haploid genome contains a single copy of the G-CSF gene. The RT-PC R analysis of several feline cell lines revealed expression of G-CSF mRNA i n response to lipopolysaccharide stimulation. Sequence analysis of genomic and cDNA clones indicated that the intron-exon junction structure is conser ved between the human and the feline G-CSF genes. The G-CSF coding region e ncodes a predicted protein of 195 amino acids including a signal sequence o f 21 amino acids. The feline G-CSF amino acid sequence shares a high degree of identity with the canine (90.8%), human (87.4%), ovine (83.9%), bovine (82.8%), porcine (80.5%), murine (70.7%) and rat (66.8%) G-CSF. The feline G-CSF expressed in insect cells using recombinant baculovirus vector was bi ologically active as measured in a proliferation assay using NFS-60 cells a nd an induction assay of leukocytes in cats. (C) 2001 Elsevier Science B.V. All rights reserved.