On the role of galectins in signal transduction.

Galectins are a family of proteins that bind to beta-galactoside carbohydrate structure through their carbohydrate recognition domains (CRDs). These proteins have been shown to be involved in multiple biological functions such as cell-matrix and cell-cell interactions, cell proliferation, cell differentiation, cellular transformation, or apoptosis mainly through their binding properties to specific ligands. Signal transduction should be dramatically affected and changed in the process of those biological functions; namely, galectins can also be involved in several signal transduction pathways. This chapter discusses the role of galectins in signal transduction, dividing into extracellular and intracellular galectins. In addition, we will indicate the methods to identify the interactions of galectins in signal transduction.