Preferential Distribution of Boron to Developing Tissues Is Mediated by the Intrinsic Protein OsNIP3. Issue 2 (7th December 2017)

• Record Type: Journal Article
• Authors: Shao, Ji Feng; Yamaji, Naoki; Liu, Xin Wei; Yokosho, Kengo; Shen, Ren Fang; Ma, Jian Feng
• Is Part Of: Plant physiology. Volume 176:Issue 2(2018)
• Page Start: 1739
• Page End: 1750
• Publication Date: 2017-12-07
• Subjects: Plant physiology -- Periodicals; Botany -- Periodicals; Periodicals; Electronic journals; 571.2
• DOI: 10.1104/pp.17.01641
• Languages: English
• ISSNs: 0032-0889

Abstract

Abstract : Boron is preferentially delivered in rice to developing tissues by OsNIP3 ; 1 located in the nodes, which is regulated at both the transcriptional and protein levels in response to external boron concentration. Abstract: Boron is especially required for the growth of meristem and reproductive organs, but the molecular mechanisms underlying the preferential distribution of B to these developing tissues are poorly understood. Here, we show evidence that a member of nodulin 26-like intrinsic protein (NIP), OsNIP3;1, is involved in this preferential distribution in rice ( Oryza sativa ). OsNIP3 ; 1 was highly expressed in the nodes and its expression was up-regulated by B deficiency, but down-regulated by high B. OsNIP3;1 was polarly localized at the xylem parenchyma cells of enlarged vascular bundles of nodes facing toward the xylem vessels. Furthermore, this protein was rapidly degraded within a few hours in response to high B. Knockout of this gene hardly affected the uptake and root-to-shoot translocation of B, but altered B distribution in different organs in the above-ground parts, decreased distribution of B to the new leaves, and increased distribution to the old leaves. These results indicate that OsNIP3;1 located in the nodes is involved in the preferential distribution of B to the developing tissues by unloading B from the xylem in rice and that it is regulated at both transcriptional and protein level in response to external B level.