Inhibitor-type lectin that may regulate the correct polymerization of BGLU23/PYK10 upon tissue damage. Activates BGLU21, BGLU22 and BGLU23. Component of the PYK10 complex, at least composed of PYK10/BGLU23, BGLU21, BGLU22, JAL22, JAL23, PBP1/JAL30, PBP2/JAL31, JAL32, JAL33, JAL34, JAL35, GLL22 and GLL23. Expressed exclusively in roots. Induced by NAI1 (at protein level). Reduced tissue damage-mediated BGLU23/PYK10 activation. Larger PYK10 complexes. Belongs to the jacalin lectin family. PubMed:18467340 shows that PBP1 inhibits polymerization of PYK10 complex, while in PubMed:19965874, PBP1 activates purified PYK10.