Sato Sachiko, Iwaki Jun, Hirabayashi Jun
Axe of Infectious and Immune Diseases, CHU de Quebec-Université Laval Research Centre, Faculty of Medicine, and Research Centre for Infectious Diseases, Laval University, Quebec City, Canada.
Tokyo Chemical Industry Co., Ltd., Tokyo, Japan.
Semin Immunol. 2025 Mar;77:101926. doi: 10.1016/j.smim.2024.101926. Epub 2024 Dec 24.
In this review, we aim to explore the multifaceted roles of galectins in host defense from a broader perspective, particularly regarding their functions when host integrity is compromised. Numerous comprehensive reviews on galectin functions in immunity have already been published. For researchers new to the field, this wealth of information may create an impression of galectins as proteins involved in a wide array of biological processes. Furthermore, due to the heterogeneity of galectin ligands, glycans, there is a risk of perceiving galectin-specific functions as ambiguous, potentially obscuring their core biological significance. To address this, we revisit foundational aspects, focusing on the significance of the recognition of galactose, a "late-comer" monosaccharide in evolutionary terms, provide an overview of galectin glycan binding specificity, with emphasis on the potential biological importance of each carbohydrate-recognition domain. We also discuss the biological implications of the galectin location paradox wherein these cytosolic lectins function in host defense despite their glycan ligands being synthesized in the secretory pathway. Additionally, we examine the role of galectins in liquid-liquid phase separation on membranes, which may facilitate their diverse functions in cellular responses. Through this approach, we aim to re-evaluate the complex and diverse biological roles of galectins in host defense.
在本综述中，我们旨在从更广泛的角度探讨半乳糖凝集素在宿主防御中的多方面作用，特别是在宿主完整性受损时它们的功能。关于半乳糖凝集素在免疫中的功能，已经发表了许多全面的综述。对于该领域的新手研究人员来说，这些丰富的信息可能会给人一种印象，即半乳糖凝集素是参与广泛生物过程的蛋白质。此外，由于半乳糖凝集素配体聚糖的异质性，存在将半乳糖凝集素特异性功能视为模糊不清的风险，这可能会掩盖它们的核心生物学意义。为了解决这个问题，我们重新审视基础方面，重点关注半乳糖这种在进化上属于“后来者”的单糖识别的重要性，概述半乳糖凝集素聚糖结合特异性，强调每个碳水化合物识别结构域潜在的生物学重要性。我们还讨论了半乳糖凝集素定位悖论的生物学意义，即尽管这些胞质凝集素的聚糖配体是在分泌途径中合成的，但它们仍在宿主防御中发挥作用。此外，我们研究了半乳糖凝集素在膜上液 - 液相分离中的作用，这可能有助于它们在细胞反应中发挥多种功能。通过这种方法，我们旨在重新评估半乳糖凝集素在宿主防御中的复杂多样的生物学作用。
