similar to SBP1 (S-RIBONUCLEASE BINDING PROTEIN 1), protein binding / zinc ion binding [Arabidopsis thaliana] (TAIR:AT1G45976.1); similar to unknown [Populus trichocarpa] (GB:ABK93023.1); contains InterPro domain S-ribonuclease binding protein, SBP1, pollen (InterPro:IPR017066)