Galectin-1 is a protein that in humans is encoded by the LGALS1gene.[5][6]
Gene and protein
LGALS1 contains four exons. The galectin-1 protein is 135 amino acids in length and highly conserved across species. It can be found in the nucleus, the cytoplasm, the cell surface and in the extracellular space. Galectins in general lack a traditional signal sequence, but are still secreted across the plasma membrane. This non-traditional secretion requires a functional glycan binding site. Galectin 1 contains a single carbohydrate recognition domain through which it can bind glycans both as a monomer and as a homodimer. Dimers are non-covalently bound and will spontaneously disassociate in low concentration.[7] Galectin 1 does not bind glycans when oxidized.[8] Having 6 cysteine residues, the oxidation state has a significant effect on the protein structure. The oxidized form is reported to have alternative functions not involving carbohydrate binding.[9]
Function
The galectins are a family of beta-galactoside-binding proteins implicated in modulating cell-cell and cell-matrix interactions. Galectin-1 may act as an autocrine negative growth factor that regulates cell proliferation.[10] Galectin-1 expression in Hodgkin Lymphoma has also been shown to mediate immunosuppression of CD8+ T-cells.[11]
It has been linked to the inflammatory process in HIV individuals, and some research suggest that Gal-1 could be related to the HIV-1 latency.[12]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Gitt MA, Barondes SH (January 1991). "Genomic sequence and organization of two members of a human lectin gene family". Biochemistry. 30 (1): 82–89. doi:10.1021/bi00215a013. PMID1988031.
^Outenreath RL, Jones AL (November 1992). "Influence of an endogenous lectin substrate on cultured dorsal root ganglion cells". Journal of Neurocytology. 21 (11): 788–795. doi:10.1007/bf01237904. PMID1431997. S2CID20883530.
^Kadoya T, Horie H (June 2005). "Structural and functional studies of galectin-1: a novel axonal regeneration-promoting activity for oxidized galectin-1". Current Drug Targets. 6 (4): 375–383. doi:10.2174/1389450054022007. PMID16026256.