Chemokine: small cytokines, including a number of secreted growth factors and interferons involved in mitogenic, chemotactic, and inflammatory activity; distinguished from other cytokines by their receptors, which are G-protein coupled receptors; divided into 4 subfamilies based on the arrangement of the two N-terminal cysteines; some members can bind multiple receptors and many chemokine receptors can bind more than one chemokine; this redundancy allows precise control in stimulating the immune system and in contributing to the homeostasis of a cell; when expressed inappropriately, chemokines play a role in autoimmune diseases, vascular irregularities, graft rejection, neoplasia, and allergies; exist as monomers, dimers and multimers, but are believed to function as monomers; found only in vertebrates and a few viruses. See CDs: Chemokine_CXC (cd00273), Chemokine_CC (cd00272), Chemokine_C (cd00271), and Chemokine_CX3C (cd00274) for chemokine subgroups.

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2K03_C       8 SYRCPCRFFESH-VARANVKHLKIL-NTPNCA-CQIVARLKNNnRQVCIDPKLKWIQEYLEKCLN 69
Cdd:cd00273  1 ELRCRCIKTTSGfVHPKSIKKLEVIpPGPHCPnTEIIATLKNG-RKVCLNPEAPWVQKIIKKLLK 64

Chemokine_CXC: 1 of 4 subgroup designations based on the arrangement of the two N-terminal cysteine residues; includes a number of secreted growth factors and interferons involved in mitogenic, chemotactic, and inflammatory activity; many members contain an RCxC motif which may be a general requirement for binding to CXC chemokine receptors; those with the ELR motif are chemotatic for neutrophils and have been shown to be angiogenic, while those without the motif act on T and B cells, and are typically angiostatic; exist as monomers and dimers, but are believed to be functional as monomers; found only in vertebrates and a few viruses. See CDs: Chemokine (cd00169) for the general alignment of chemokines, or Chemokine_CC (cd00272), Chemokine_C (cd00271), and Chemokine_CX3C (cd00274) for the additional chemokine subgroups.

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2K03_C       8 SYRCPCRFFESH-VARANVKHLKIL-NTPNCA-CQIVARLKNNnRQVCIDPKLKWIQEYLEKCLN 69
Cdd:cd00273  1 ELRCRCIKTTSGfVHPKSIKKLEVIpPGPHCPnTEIIATLKNG-RKVCLNPEAPWVQKIIKKLLK 64

Small cytokines (intecrine/chemokine), interleukin-8 like; Includes a number of secreted growth factors and interferons involved in mitogenic, chemotactic, and inflammatory activity. Structure contains two highly conserved disulfide bonds.

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2K03_C        44 LKNNNRQVCIDPKLKWIQEYLEK 66
Cdd:pfam00048 37 LTKKGRQVCADPKAKWVQRLIKK 59

Chemokine_CXC: 1 of 4 subgroup designations based on the arrangement of the two N-terminal cysteine residues; includes a number of secreted growth factors and interferons involved in mitogenic, chemotactic, and inflammatory activity; many members contain an RCxC motif which may be a general requirement for binding to CXC chemokine receptors; those with the ELR motif are chemotatic for neutrophils and have been shown to be angiogenic, while those without the motif act on T and B cells, and are typically angiostatic; exist as monomers and dimers, but are believed to be functional as monomers; found only in vertebrates and a few viruses. See CDs: Chemokine (cd00169) for the general alignment of chemokines, or Chemokine_CC (cd00272), Chemokine_C (cd00271), and Chemokine_CX3C (cd00274) for the additional chemokine subgroups.

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2K03_C       8 SYRCPCRFFESH-VARANVKHLKIL-NTPNCA-CQIVARLKNNnRQVCIDPKLKWIQEYLEKCLN 69
Cdd:cd00273  1 ELRCRCIKTTSGfVHPKSIKKLEVIpPGPHCPnTEIIATLKNG-RKVCLNPEAPWVQKIIKKLLK 64

Intercrine alpha family (small cytokine C-X-C) (chemokine CXC); Family of cytokines involved in cell-specific chemotaxis, mediation of cell growth, and the inflammatory response.

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2K03_C          8 SYRCpCRFFES-HVARANVKHLKIlNTPNCA-CQIVARLKNNnRQVCIDPKLKWIQEYLEK 66
Cdd:smart00199  1 PLRC-CLSYTSkKIPLKRIKSYYP-TSSHCPkPAVIFTTKKG-RKVCADPKAKWVQRYIKK 58