Regulating the transport of mineral nutrients in plants is critical for maintaining homeostasis (Marschner, 2012). Plants control mineral transporter expression in response to mineral availability at various stages (Aibara and Miwa, 2014). Although transcriptional regulation of such transporters has been studied intensively, there are few reports of posttranscriptional regulation, especially translational regulation. Boron (B) is an essential micronutrient, as borate cross-links pectic polysaccharide in the primary cell wall (O'Neill et al., 2004; Marschner, 2012); however, it is toxic to plants when present in excess concentrations (Nable et al., 1997; Reid et al., 2004). B concentrations in soil solutions can be changed by natural events, such as leaching out after rainfall and accumulation after drying of topsoil water, and possibly via the decomposition of organic matter (Shorrocks, 1997; Argust, 1998; Park and Schlesinger, 2002). In soil solutions, B exists mainly as uncharged boric acid, which readily permeates cell membranes (Dordas et al., 2000). Under these circumstances, plants use different types of B transporters to cope with the narrow optimum range of B concentrations (Yoshinari and Takano, 2017). Under B deprivation, the NODULIN26-LIKE INTRINSIC PRO-TEIN5;1 (NIP5;1) and BOR1 genes are expressed in roots to support the effective translocation of B in Arabidopsis (Arabidopsis thaliana). NIP5;1 is a boric acid channel expressed mainly in epidermal cells that facilitates boric acid uptake from soil into root cells (Takano et al., 2006, 2010). BOR1 is an efflux borate transporter expressed in various cell types, including epidermis and endodermis, that exports borate out of cells toward the xylem and contributes to the translocation of