Carrier protein that may be involved in membrane-trafficking events associated with cell plate formation during cytokinesis. Binds to some hydrophobic molecules and promotes their transfer between the different cellular sites. Binds to phosphoinositides with a preference for PtdIns(5)P, PtdIns(4,5)P2 and PtdIns(3)P. Interacts with the deubiquitinating enzyme AMSH3. Mainly membrane-associated. Also cytoplasmic. Cell plate during cell division. Expressed ubiquitously with higher levels in expanding roots and leaves (at protein level). Accumulates during flower development (at protein level). 'Patella' means 'small plate' in Latin. Belongs to the patellin family.