Shmoo tip protein, substrate of Hub1p ubiquitin-like protein; mutants are defective for mating projection formation, thereby implicating Hbt1p in polarized cell morphogenesis; HBT1 has a paralog, YNL195C, that arose from the whole genome duplication.
HBT1(YDL223C) is an AMPA-R [alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor] potentiator that induces production of brain-derived neurotrophic factor (BDNF) and exhibits little agonistic effect in primary neurons. HBT1 binds to ligand-binding domain of AMPA-R in glutamate dependent manner.
