Galectin

About: Galectin is a research topic. Over the lifetime, 2076 publications have been published within this topic receiving 103409 citations. The topic is also known as: IPR001079 & Galectin.

Full-length model of the human galectin-4 and insights into dynamics of inter-domain communication.

Abstract: Galectins are proteins involved in diverse cellular contexts due to their capacity to decipher and respond to the information encoded by β-galactoside sugars. In particular, human galectin-4, normally expressed in the healthy gastrointestinal tract, displays differential expression in cancerous tissues and is considered a potential drug target for liver and lung cancer. Galectin-4 is a tandem-repeat galectin characterized by two carbohydrate recognition domains connected by a linker-peptide. Despite their relevance to cell function and pathogenesis, structural characterization of full-length tandem-repeat galectins has remained elusive. Here, we investigate galectin-4 using X-ray crystallography, small- and wide-angle X-ray scattering, molecular modelling, molecular dynamics simulations and differential scanning fluorimetry assays and describe for the first time a structural model for human galectin-4. Our results provide insight into the structural role of the linker-peptide and shed light on the dynamic characteristics of the mechanism of carbohydrate recognition among tandem-repeat galectins.

Intracellular galectins sense cytosolically exposed glycans as danger and mediate cellular responses.

Abstract: Galectins are animal lectins that recognize carbohydrates and play important roles in maintaining cellular homeostasis. Recent studies have indicated that under a variety of challenges, intracellular galectins bind to host glycans displayed on damaged endocytic vesicles and accumulate around these damaged organelles. Accumulated galectins then engage cellular proteins and subsequently control cellular responses, such as autophagy. In this review, we have summarized the stimuli that lead to the accumulation of galectins, the molecular mechanisms of galectin accumulation, and galectin-mediated cellular responses, and elaborate on the differential regulatory effects among galectins.

Generation of H2O2 by human neutrophils and changes of cytosolic Ca2+ and pH of rat thymocytes in response to galactoside-binding proteins (lectins or immunoglobulins).

Abstract: In contrast to plant agglutinins, biological activities of animal/human lectins are not well defined yet Testing a panel of seven mammalian carbohydrate-binding proteins we have found that the dimeric lectin from chicken liver (CL-16) was a stimulator of H2O2 release from human neutrophils as well as effector for induction of cytosolic Ca2+ and pH increase in rat thymocytes Activity of this lectin was comparable to potent galactoside-specific plant lectins such as Viscum album L agglutinin The activities of the tested plant lectins depended significantly on their nominal carbohydrate specificity as well as on the source The results indicate that endogenous lectins may be involved in the regulation of neutrophil and lymphocyte functions by elicitation of selective biosignaling reactions

Galectin-3 and Inflammation

Abstract: Galectins are a family of β-galactoside-binding proteins that share a consensus sequence in the carbohydrate recognition domain (CRD). Galectin-3 is the most widely studied family member and can be found in the cellular cytoplasm and nucleus, as well as extracellularly in various tissues. The 30-kDa molecule contains an N-terminal proline-rich domain that is important for its oligomerization and a C-terminal CRD for carbohydrate-binding activity. Many studies have shown that galectin-3 may regulate inflammation through a variety of mechanisms. Endogenous galectin-3 has been shown to be involved in the pathogenesis of various diseases, such as fibrosis in the lung, liver, and heart, diabetes mellitus, coronary artery disease, and allergic diseases. In this review, we briefly discuss the pro- or anti-inflammatory roles, as well as potential clinical implications of galectin-3 in these disorders.