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Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion
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Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion

Published on: June 15, 2019

The complete complement of C1q-domain-containing proteins in Homo sapiens

Y Tom Tang1, Tianhua Hu, Matthew Arterburn

  • 1Biology Research, Nuvelo, Sunnyvale, CA 94085, USA.

Genomics
|June 15, 2005
PubMed

Insights

Researchers identified 31 human C1q domain-containing (C1qDC) genes, revealing conserved structures and evolutionary patterns. This gene family shows ancient origins and varied retention across species, suggesting diverse functional roles.

Area of Science:

  • Genomics
  • Evolutionary Biology
  • Structural Biology

Background:

  • The C1q domain is a conserved structural motif found in various proteins, including the C1 complex's C1q subcomponent.
  • Understanding the full complement and evolutionary history of C1q-domain-containing (C1qDC) proteins is crucial for deciphering their diverse biological functions.

Purpose of the Study:

  • To comprehensively identify and analyze the human C1qDC gene family.
  • To investigate the evolutionary relationships and conservation patterns of C1qDC proteins across different species.

Main Methods:

  • Human genome analysis to identify all C1qDC gene sequences.
  • Sequence homology analysis to classify C1qDC proteins into subfamilies.
  • Comparative genomics to trace the evolutionary history and conservation of C1qDC genes.

Main Results:

  • Identified 31 independent human C1qDC gene sequences.
  • Predominant C1qDC protein structure includes a signal peptide, collagen-like region, and C1q domain with conserved hydrophobic core residues.
  • Proposed a 3-subfamily classification based on sequence homology.
  • Observed evidence of strict orthology and functional specialization in some C1qDC genes, alongside gene duplication and diversification in others.
  • Detected ancient origins of C1qDC proteins, with members in eubacteria, but sporadic presence in some eukaryotes.

Conclusions:

  • The human genome encodes 31 C1qDC genes with conserved structural features and evolutionary dynamics.
  • C1qDC proteins have ancient origins and have undergone both conserved functional roles and species-specific diversification.
  • The sporadic presence of C1qDC genes in eukaryotes highlights dynamic evolutionary retention or loss patterns for this gene family.

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