Galectin 9 Rabbit Polyclonal Antibody (ER1909-31)

UNIPROT #

O00182

PROTEIN NAME

Galectin 9

SYNONYMS

36 kDa beta-galactoside-binding lectin antibody;Ecalectin antibody;Gal-9 antibody;galectin 9 antibody;Galectin-9 antibody;galectin9 antibody;HOM HD 21 antibody;HOMHD21 antibody;HUAT antibody;Lectin galactoside binding soluble 9 antibody;LEG9_HUMAN antibody;LGAL S9 antibody;LGALS 9 antibody;Lgals9 antibody;LGALS9A antibody;MGC117375 antibody;MGC125973 antibody;MGC125974 antibody;Tumor antigen HOM-HD-21 antibody;UAT antibody;Urate transporter/channel antibody;Urate transporter/channel protein antibody

SUBCELLULAR LOCATION

Cytoplasm, Nucleus, Secreted.

FUNCTION

The protein has N- and C- terminal carbohydrate-binding domains connected by a link peptide. Multiple alternatively spliced transcript variants have been found for this gene. Galectin-9 is one of the most studied ligands for HAVCR2 (TIM-3) and is expressed on various tumor cells. However, it can also interact with other proteins (CLEC7A, CD137, CD40). For example, an interaction with CD40 on T-cells inhibits their proliferation and induces cell death. Galectin-9 also has important cytoplasmic, intracellular functions and controls AMPK in response to lysosomal damage that can occur upon exposure to endogenous and exogenous membrane damaging agents such as crystalline silica, cholesterol crystals, microbial toxins, proteopathic aggregates such as tau fibrils and amyloids, and signaling pathways inducing lysosomal permeabilization such as those initiated by TRAIL. Mild lysosomal damage, such as that caused by the anti-diabetes drug metformin may contribute to the therapeutic action of metformin by activating AMPK. The mechanism of how Galectin-9 activates AMPK involves recognition of exposed lysosomal lumenal glycoproteins such as LAMP1, LAMP2, SCRAB2, TMEM192, etc., repulsion of deubiquitinating enzyme USP9X, increased K63 ubiquitination of TAK1 (MAP3K7) kinase, which in turn phopshorylates AMPK and activates it. This signaling cascade directly links Galectin-9 intracellular function with ubiqutin systems. Galectin-9, through its regulation of AMPK, a kinase that negatively regulates mTOR, cooperates with Galectin-8-based effects to inactivate mTOR downstream of the lysosomal damaging agents and conditions.