APP1/NTL9-CalS8 module ensures proper phloem differentiation by stabilizing callose accumulation and symplastic communication

Bibliographische Detailangaben
Veröffentlicht in:	The New phytologist. - 1979. - 242(2024), 1 vom: 20. März, Seite 154-169
1. Verfasser:	Liu, Jie (VerfasserIn)
Weitere Verfasser:	Fan, Yongxiao, Liu, Yao, He, Meiqing, Sun, Yanke, Zheng, Qi, Mi, Lingyu, Liu, Junzhong, Liu, Wencheng, Tang, Ning, Zhao, Xiang, Hu, Zhubing, Guo, Siyi, Yan, Dawei
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2024
Zugriff auf das übergeordnete Werk:	The New phytologist
Schlagworte:	Journal Article Arabidopsis thaliana CalS8 NAC callose phloem root sieve element symplastic communication 9064-51-1 mehr... 1,3-beta-glucan synthase EC 2.4.1.34 Arabidopsis Proteins Glucans Glucosyltransferases EC 2.4.1.-

Beschreibung
Zusammenfassung:	© 2024 The Authors New Phytologist © 2024 New Phytologist Foundation. Phloem sieve elements (PSE), the primary conduits collaborating with neighboring phloem pole pericycle (PPP) cells to facilitate unloading in Arabidopsis roots, undergo a series of developmental stages before achieving maturation and functionality. However, the mechanism that maintains the proper progression of these differentiation stages remains largely unknown. We identified a gain-of-function mutant altered phloem pole pericycle 1 Dominant (app1D), producing a truncated, nuclear-localized active form of NAC with Transmembrane Motif 1-like (NTL9). This mutation leads to ectopic expression of its downstream target CALLOSE SYNTHASE 8 (CalS8), thereby inducing callose accumulation, impeding SE differentiation, impairing phloem transport, and inhibiting root growth. The app1D phenotype could be reproduced by blocking the symplastic channels of cells within APP1 expression domain in wild-type (WT) roots. The WT APP1 is primarily membrane-tethered and dormant in the root meristem cells but entries into the nucleus in several cells in PPP near the unloading region, and this import is inhibited by blocking the symplastic intercellular transport in differentiating SE. Our results suggest a potential maintenance mechanism involving an APP1-CalS8 module, which induces CalS8 expression and modulates symplastic communication, and the proper activation of this module is crucial for the successful differentiation of SE in the Arabidopsis root
Beschreibung:	Date Completed 08.03.2024 Date Revised 08.03.2024 published: Print-Electronic Citation Status MEDLINE
ISSN:	1469-8137
DOI:	10.1111/nph.19617