Homologous Superfamily

C-type lectin fold (IPR016187)

Short name: CTDL_fold

Overlapping entries


Lectins occur in plants, animals, bacteria and viruses. Initially described for their carbohydrate-binding activity [PMID: 14533786], they are now recognised as a more diverse group of proteins, some of which are involved in protein-protein, protein-lipid or protein-nucleic acid interactions [PMID: 12223269]. There are at least twelve structural families of lectins, of which C-type (Ca+-dependent) lectins is one. C-type lectins can be further divided into seven subgroups based on additional non-lectin domains and gene structure: (I) hyalectans, (II) asialoglycoprotein receptors, (III) collectins, (IV) selectins, (V) NK group transmembrane receptors, (VI) macrophage mannose receptors, and (VII) simple (single domain) lectins [PMID: 15476922].

This entry represents a structural domain found in C-type lectins, as well as in other proteins, including:

  • The N-terminal domain of aerolysin [PMID: 7510043] and the N-terminal domain of the S2/S3 subunit of pertussis toxin [PMID: 8637000].
  • The C-terminal domain of invasin [PMID: 10514372] and intimin [PMID: 10890451].
  • Link domain, which includes the Link module of TSG-6 [PMID: 12972412] (a hyaladherin with important roles in inflammation and ovulation) and the hyaluronan binding domain of CD44 (which contains extra N-terminal beta-strand and C-terminal beta-hairpin) [PMID: 14992719].
  • Endostatin [PMID: 9724722] and the endostatin domain of collagen alpha 1 (XV) [PMID: 966814], these domains being decorated with many insertions in the common fold.
  • The noncollagenous (NC1) domain of collagen IV, which consists of a duplication of the C-type lectin domain, with segment swapping within and between individual domains [PMID: 12011424].
  • Sulphatase-modifying factors (C-alpha-formyglycine-generating enzyme), where the fold is decorated with many additional structures [PMID: 16041070, PMID: 15687489].
  • The C-terminal domain of the major tropism determinant (Mtd), where the fold is decorated with many additional structures, and has an overall similarity to the sulphatase modifying factor family but lacking the characteristic disulphide [PMID: 16170324].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.