CDD/SPARCLE: functional classification of proteins via subfamily domain architectures

Nucleic Acids Res. 2017 Jan 4;45(D1):D200-D203. doi: 10.1093/nar/gkw1129. Epub 2016 Nov 29.


NCBI's Conserved Domain Database (CDD) aims at annotating biomolecular sequences with the location of evolutionarily conserved protein domain footprints, and functional sites inferred from such footprints. An archive of pre-computed domain annotation is maintained for proteins tracked by NCBI's Entrez database, and live search services are offered as well. CDD curation staff supplements a comprehensive collection of protein domain and protein family models, which have been imported from external providers, with representations of selected domain families that are curated in-house and organized into hierarchical classifications of functionally distinct families and sub-families. CDD also supports comparative analyses of protein families via conserved domain architectures, and a recent curation effort focuses on providing functional characterizations of distinct subfamily architectures using SPARCLE: Subfamily Protein Architecture Labeling Engine. CDD can be accessed at

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Computational Biology / methods*
  • Databases, Protein*
  • Information Dissemination
  • Internet
  • Protein Interaction Domains and Motifs*
  • Proteins* / chemistry
  • Proteins* / classification
  • Proteins* / genetics


  • Proteins