Cloning, genomic sequence, and chromosome mapping of Scyb11, the murine homologue of SCYB11 (alias beta R1/H174/SCYB9B/I-TAC/IP-9/CXCL11)

A T-cell attracting CXC chemokine phylogenetically related to MIG and SCYB1 0 was recently characterized and termed SCYB11 (alias beta R1/H174/SCYB9B/I -TPLC/IP-9/ CXCL11). Here, we cloned the cDNA of the murine homologue of th is protein, Scyb11, from interferon-gamma/lipopolysaccharide-stimulated RAW 264.7 mouse macrophage-like cells. The nucleotide sequence of Scyb11 shares 63% identity with its human counterpart. It encodes a 100 amino acid immat ure protein of 11,265 Da which contains a putative signal peptide of 21 ami no acids. The molecular mass of the mature protein was calculated to be 9,1 13 Da. Sequence identity of the murine and human SCYB11 proteins is 68%. Ph ylogenetic tree analysis of mouse CXC chemokines places SCYB11 together wit h the murine homologues of MIG and SCYB10 (Crg-2/muIP-10) on an individual branch. A genomic sequence was obtained by genome walking and subcloning DN A fragments from a BAC clone containing Scyb11. Like human SCYB11, Scyb11 c ontains 4 exons with intron/exon boundaries at positions comparable to the human gene. Whereas introns 2 and 3 are of similar length in the murine and human genes, intron 1 of Scyb11 contains 1,260 bp more than intron 1 of th e human gene. Intron 1 of Scyb11 is also characterized by a 201-bp stretch with repetitive sequences of high cryptic simplicity. Using a BAC clone con taining Scyb11, this gene could be mapped to chromosome 5 at position 5E3. Since human SCYB11 is localized on 4q21.2, this result confirms the mouse/h uman homology of the two chromosome regions. Copyright (C) 2000 S. Karger A G, Basel.