Cloning and characterization of chicken stromal cell derived factor-1.

Stromal cell derived factor-1, SDF-1, belongs to the CXC family of chemokines and has been identified in mammals, amphibians, and fish. This chemokine has a diverse array of functions in organogenesis, hematopoeisis, B cell development and recruitment of immune system cells. Here, we report the cloning of the chicken SDF-1 ortholog and examine its temporal and spatial expression. The chicken SDF-1 cDNA contained an open reading frame encoding a predicted protein of 89 amino acids, which shared 40-75% identity to SDF-1 protein in other species. Protein folding simulation predicted a tertiary structure very similar to that obtained for human SDF-1. Recombinant chicken SDF-1 was produced using a prokaryotic expression system and the recombinant protein was shown to be biologically active in a calcium flux assay. The SDF-1 gene was found to be expressed ubiquitously and constitutively in adult tissues and was present as early as the primitive streak stage of chicken embryos.