Abstract
The endogenous galectin-3 is a carbohydrate-binding protein of Mr∼30,000 serving in the cytoplasm and on the cell surface as a receptor for ligands containing poly-N-acetyllactosamine sequences. In addition, galectin-3 has been demonstrated to be associated in the nucleus with ribonucleoprotein complexes and to act as a pre-mRNA splicing factor and to be involved in spliceosome assembly. However, little is known about either its nuclear localization or its ligand(s), respectively. We demonstrate directly here that galectin-3 is associated with the RNA protein skeleton of the nucleus, i.e., the nuclear matrix, and binds with single-stranded DNA (ssDNA) and with RNA. The affinity of binding was determined to be 2.3 μM. Lactose, which inhibits galectin-3 binding to glycoconjugates, failed to inhibit either galectin-3-ssDNA or galectin-3-RNA binding. Galectin-3 exhibited the highest affinity to poly(A) ribonucleotide homopolymers. The results presented here shows that galectin-3 may act as a RNA-binding protein in the nuclear matrix in a noncarbohydrate-dependent manner.
Original language | English (US) |
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Pages (from-to) | 292-303 |
Number of pages | 12 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 217 |
Issue number | 1 |
DOIs | |
State | Published - 1995 |
Externally published | Yes |
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology