Troncoso Maria F, Elola Maria T, Croci Diego O, Rabinovich Gabriel A
Institute of Biological Chemistry and Physicochemistry (UBA-CONICET), Department of Biological Chemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina.
Front Biosci (Schol Ed). 2012 Jan 1;4(3):864-87. doi: 10.2741/s305.
Galectins (GALs) are evolutionarily-conserved lectins defined by at least one carbohydrate recognition domain (CRD) with affinity for beta-galactosides and conserved sequence motifs. Although the biological roles of some members of this family, including the 'proto-type' GAL-1 and the 'chimera-type' GAL-3 have been widely studied, the functions of 'tandem-repeat' galectins are just emerging. The subgroup of 'tandem-repeat' galectins (GAL-4, -6, -8, -9, and -12) contain two distinct CRDs, connected by a linker peptide. Here we integrated and distilled the available information on 'tandem-repeat' galectins, their specific structures, potential ligands and biological activities in inflammatory and neoplastic diseases. While GAL-4 has been implicated in inflammatory bowel diseases, either as a pro-inflammatory or pro-apoptotic mediator, GAL-8 plays roles in autoimmune diseases such as rheumatoid arthritis and lupus erythematosus and modulates tumor progression. GAL-9 controls allergic inflammation and Th1/Th17-mediated autoimmunity and has prognostic value in certain tumor types. Finally, GAL-12 plays important roles in adipocyte physiology. Although this information is just emerging, further studies are needed to dissect the biological roles of 'tandem-repeat' galectins in health and disease.
半乳糖凝集素（GALs）是进化上保守的凝集素，由至少一个对β-半乳糖苷具有亲和力的碳水化合物识别结构域（CRD）和保守的序列基序定义。尽管该家族中一些成员的生物学作用，包括“原型”GAL-1和“嵌合型”GAL-3，已得到广泛研究，但“串联重复”半乳糖凝集素的功能才刚刚开始显现。“串联重复”半乳糖凝集素亚组（GAL-4、-6、-8、-9和-12）包含两个不同的CRD，由一个连接肽连接。在这里，我们整合并提炼了关于“串联重复”半乳糖凝集素、它们的特定结构、潜在配体以及在炎症和肿瘤性疾病中的生物学活性的现有信息。虽然GAL-4已被认为与炎症性肠病有关，作为促炎或促凋亡介质，但GAL-8在类风湿性关节炎和红斑狼疮等自身免疫性疾病中发挥作用，并调节肿瘤进展。GAL-9控制过敏性炎症和Th1/Th17介导的自身免疫，并且在某些肿瘤类型中具有预后价值。最后，GAL-12在脂肪细胞生理学中发挥重要作用。尽管这些信息才刚刚出现，但仍需要进一步研究来剖析“串联重复”半乳糖凝集素在健康和疾病中的生物学作用。
