Galectin-7

Galectin-7 is a protein that in humans is encoded by the LGALS7 gene.

The galectins are a family of beta-galactoside-binding lectins involved in modulating cell–cell and cell–matrix interactions. LGALS7 is specifically expressed in keratinocytes and at all stages of epidermal differentiation, including the basal and suprabasal layers. Expression is moderately repressed by retinoic acid. In tissue sections, galectin-7 localizes primarily to basal keratinocytes but is also found, at lower levels, in suprabasal layers where it concentrates at sites of cell–cell contact. Its down-regulation in cultured keratinocytes suggests a role in adhesion-related growth control.

Galectin-7, like other galectins, binds carbohydrate structures containing galactose. Galactosides contribute to glycoprotein architecture and to processes such as oligosaccharide hydrolysis, and the structural diversity of these sugars underlies the selective affinity of galectins for their glycan ligands. Consistent with its keratinocyte-specific expression, galectin-7 is abundant in the epidermis and other stratified epithelia.

The LGALS7 gene participates in fundamental cellular processes such as apoptosis and cell–cell interactions. Galectin-7 contributes to epithelial maintenance, wound repair, and cellular stress responses, and shows context-dependent roles in immunity, infection, and cancer. Its carbohydrate-binding specificity gives rise to distinct signaling outputs, making therapeutic targeting challenging. Galectins are classified into proto-type, tandem-repeat-type, and chimera-type subfamilies, and their functional diversity reflects differences in localization, glycan affinity, and structural organization.