Involved in the basipetal transport of auxin (IAA) that modulates growth and organs organization, as well as cell differentiation. Regulates shoot apical meristem (SAM) organization in the peripheral zone. Required for initial meristematic divisions in the epidermal/lateral root cap leading to the formation of epidermal cells and a clone of lateral root cap cells, as well as for the maintenance of the radial pattern of cell specification in the root, thus regulating the distinction between the lateral root cap and epidermis. Together with WIH peptides, promotes megasporogenesis. Expressed in seedlings, roots, leaves, stems, apex, siliques and flowers. Present in ovules, prominently in nucellus and integuments. Strongly expressed in all types of meristems, including the shoot apical meristem (SAM) and lateral organ primordia. Also detected in the lamina of the cotyledons, especially in the mesophyll and vascular bundles. In leaf primorida preferentially present in vascular strands and at the distal tip of the leaflet. In the floral meristem, first detected in flanking sepal primordia, and later expressed in stamens and carpels in flowers. Severe dwarfism combined with twisted and malformed organs, and sterility. Loss of initial meristematic divisions in the epidermal/lateral root cap. Defection in basipetal transport of auxin (IAA) leading to several development aberrations. 'Ekeko' is derived from Inca language (quechua) for small and hunchbacked fortune god. Belongs to the tetraspanin (TM4SF) family.