May be involved in cooperative interactions with calmodulins or calmodulin-like proteins (By similarity). Recruits calmodulin (CaM) calcium sensor proteins to cortical microtubule arrays, thus being a potential scaffold in cellular signaling and trafficking (PubMed:29976837, PubMed:30407556). Binds to microtubules (MTs) and promotes MT assembly and dynamics to modulate pavement cell (PC) morphogenesis via cellulose deposition-dependent anisotropic cell expansion triggered by cellulose synthase complexes (CSCs) (PubMed:29976837, PubMed:30407556). May associate with nucleic acids and regulate gene expression at the transcriptional or post-transcriptional level (By similarity). Binds to multiple calmodulin (CaM) in the presence of Ca(2+) and CaM-like proteins. Localized to microtubules (MTs) arrays in dynamic pattern, including cortical MT in leaf pavement and hypocotyl epidermal cells (in a discontinuous and punctate manner corresponding to indentation regions), as well as preprophase bands, mitotic spindles, and phragmoplasts of mitotic cells in root tips. Expressed mostly in vegetative tissues including older parts of the root, cotyledons, leaves and shoot apical meristems (SAM) (PubMed:30407556). Present at low levels in pollen, siliques and seeds (PubMed:30407556). In leaves and hypocotyls, mostly observed in vascular tissues (PubMed:30407556). In root tips, restricted to the lateral root cap of primary and lateral root meristems (PubMed:30407556). Abnormal pavement cell morphogenesis in cotyledons characterized by reduced interdigitation associated with altered microtubules organization and dynamics and reduced rates of cellulose deposition in anticlinal cell walls thus correleted with a reduced anisotropic cell expansion (PubMed:29976837, PubMed:30407556). Hypersensitivity to the microtubule-disrupting drug oryzalin (PubMed:29976837). Belongs to the IQD family.