Required for proliferation and differentiation of shoot stem cells in the shoot apical meristem (SAM), thus determining the appropriate balance between the maintenance of shoot stem cells and their differentiation into other aboveground plant parts via the control of subcellular localization and intercellular trafficking of STM in the shoot apex. Prevents intracellular trafficking of STM to the plasma membrane in cells in the peripheral shoot meristem region thus facilitating STM recycling to the nucleus to maintain stem cells. Interacts with and regulates subcellular localization and trafficking of STM. Accumulates in vascular tissues, leaf primordia and developing flowers (PubMed:29259105). Highly expressed in both vegetative and inflorescence shoot apical meristems (SAMs) (PubMed:29742441, PubMed:29259105). No visible phenotypes. Plants lacking both FTIP3 and FTIP4 have a dwarf and bushy phenotype due to an accelerated stem cell differentiation causing early termination of shoot apices associated with an increased STM localization to the plasma membrane, but compromises nuclear localization. Belongs to the MCTP family.