7cyb

Publication Abstract from PubMed

The gene for galectin-13 (Gal-13, placental protein 13) is only present in primates, and its low expression level in maternal serum may promote pre-eclampsia. In the present study, we used pull-down experiments and biolayer interferometry to assess the interaction between Gal-13 and actin. These studies uncovered that human Gal-13 (hGal-13) and Saimiri boliviensis boliviensis (sGal-13) strongly bind to alpha- and beta/gamma-actin, with Ca2+ and ATP significantly enhancing interactions. This in turn suggests that h/sGal-13 may inhibit myosin-induced contraction when vascular smooth muscle cells undergo polarization. Here, we solved the crystal structure of sGal-13 bound to lactose and found that it exists as a monomer in contrast to hGal-13 that is a dimer. The distribution of sGal-13 in HeLa cells is similar to that of hGal-13, indicating that monomeric Gal-13 is the primary form in cells. Even though sGal-13 also binds to actin, hGal-13 ligand binding site mutants do not influence hGal-13/actin binding, whereas the monomeric mutant C136S/C138S binds to actin more strongly than wild type hGal-13. Overall, our study demonstrates that monomeric Gal-13 binds to actin, an interaction that is independent of the galectin canonical ligand binding site.

Actin binding to galectin-13/placental protein-13 occurs independently of the galectin canonical ligand binding site.,Li X, Yao Y, Liu T, Gu K, Han Q, Zhang W, Ayala GJ, Liu Y, Na H, Yu J, Zhang F, Mayo KH, Su J Glycobiology. 2021 May 31. pii: 6290097. doi: 10.1093/glycob/cwab047. PMID:34080003^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.