Function

Galectin (GAL) are lectins which bind β-galactosidase (BGAL). GAL contains a carbohydrate recognition domain (CRD) residues 113-250[1].

  • GAL-1 is thought to play a role as autocrine negative growth factor that regulates cell proliferation.
  • GAL-2 is expressed primarily in gastrointestinal tract.
  • GAL-3 has broad biological functionality.
  • GAL-4 has 2 CRDs.
  • GAL-5 is found in rat is a β-galactoside binding lectin[2].
  • GAL-7 is associated with epithelial cells.
  • GAL-8 has a role in cellular defense against bacterial infection and vacuolar damage.
  • GAL-9 affects eosinophil survival.
  • GAL-10 or Charcot-Leyden crystal protein acts on biological membranes to regulate the multifunctional lysophospholipids.
  • GAL-13 is a placental protein which does not bind β-galactosides.

Relevance

GAL are known to inhibit chronic inflammation[3]. GAL-3 has a role in experimental autoimmune encephalomyelitis and melanoma methastasis[4].

Structural highlights

The CRD is a β-sandwich long enough to bind a tetrasaccharide. A [5]. Water molecules shown as red spheres.

3D structures of galectin

Galectin 3D structures


Structure of human galectin-1 complex with lactose, mercaptoethanol and sulfate (PDB entry 1w6o)

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

Michal Harel, Alexander Berchansky, Joel L. Sussman