Figure S2 Western blot analysis of the specificity of anti-rCsISG15 antibodies. rCsISG15 (lane 2) and rCsFerM (lane 3) were subjected to SDS-PAGE (upper panel) or immunoblot analysis with antiserum against rCsISG15 (lower panel). Lane 1, protein marker. (TIF) Figure S3 Alignment of the amino acid sequences of ISG15 homologues. Dots denote gaps introduced for maximum matching. Numbers in brackets indicate overall sequence identities between CsISG15 and the compared sequences. The residues that are conserved among all the aligned sequences are in black; the residues that are $75% identical among the aligned sequences are in grey. 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Sun J, Zhao L, Sun L (2011) Interleukin-8 of Cynoglossus semilaevis is a chemoattractant with immunoregulatory property. Fish Shellfish Immunol 30: 1362–1367. PLOS ONE | www.plosone.org 10 September 2012 | Volume 7 | Issue 9 | e44884