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Colliers de Perles

The expressions "Collier de Perles", "Colliers de Perles" are covered by a copyright when used for amino acid sequence graphical representations. If used, please refer to Ruiz, M. and Lefranc, M.-P. (2002) [6].

IMGT Colliers de Perles [1] are 2D graphical representations of the V-REGION, V-DOMAIN and C-DOMAIN of the immunoglobulin (IG) and T cell receptor (TR), and of the G-DOMAIN of the major histocompatibility (MH), based on the IMGT unique numbering [1]. Conserved hydrophobic amino acids are highlighted.

IMGT Colliers de Perles also apply to V-LIKE-DOMAIN and C-LIKE-DOMAIN from chains other than IG and TR and to G-LIKE-DOMAIN from chains other than MH.


IMGT Colliers de Perles 2D representations provide information on the amino acid positions in the beta-strands and loops of the V-REGION [1-5] and V-DOMAIN [6]. IMGT Colliers de Perles allow to quickly visualize amino acids which are important for the 3D structural configuration [7], and to delimit the standardized FR-IMGT and CDR-IMGT.

IMGT Colliers de Perles representation are of great interest for all sequences with V-LIKE-DOMAIN(s) which belong to the V-set of the Ig superfamily [1]. This includes non-rearranging sequences in vertebrates (Xenopus CTXg1, human CD4, etc.) and in invertebrates (drosophila amalgam, drosophila fasciclin II, etc.) [1-5]. The IMGT Colliers de Perles are particularly useful if no 3D structure is available.

IMGT Colliers de Perles are generated with the IMGT/Colliers de Perles tool, developed by Gérard Mennessier (LPM, Montpellier, France). IMGT/Colliers de Perles computer program automatically provides the 2D representation starting from linear amino acid sequences of V-REGIONs.

FR-IMGT and CDR-IMGT are indicated for the V-REGION, V-DOMAIN and V-LIKE-DOMAIN [1].


Strand and loop delimitations are indicated for C-DOMAIN and C-LIKE-DOMAIN.


Strand, turn and helix delimitations are indicated for the G-DOMAIN and G-LIKE-DOMAIN.

The 'IMGT Collier de Perles' concept [1-7] is part of the 'NUMEROTATION' concept of IMGT-ONTOLOGY[8]

[1] Lefranc, M-P. et al., Dev. Comp. Immunol., 27, 55-77 (2003) PMID: 12477501, LIGM:268.
[2] Lefranc, M.-P. et al., Nucleic Acids Res., 26, 297-303 (1998) PMID: 9399859, LIGM:195.
[3] Lefranc, M.-P. et al., Nucleic Acids Res., 27, 209-212 (1999) PMID: 9847182, LIGM:209.
[4] Lefranc, M.-P. and Lefranc, G., The Immunoglobulin FactsBook, Academic Press, 458 pages (2001) ISBN: 012441351X.
[5] Lefranc, M.-P. and Lefranc, G., The T cell receptor FactsBook, Academic Press, 398 pages (2001) ISBN: 0124413528.
[6] Ruiz, M. and Lefranc, M.-P., Immunogenetics, 53, 857-883 (2002) PMID: 11862387, LIGM:259.
[7] Pommié, C. et al., J. Mol. Recognit., 17, 17-32 (2004) PMID: 14872534, LIGM:284.
[8] Giudicelli, V. and Lefranc, M.-P., Bioinformatics, 15, 1047-1054 (1999) PMID: 10745995, LIGM:221 pdficon