Sugar loading of crop seeds - a partnership of phloem, plasmodesmal and membrane transport
© 2023 The Authors. New Phytologist © 2023 New Phytologist Foundation.
| Veröffentlicht in: | The New phytologist. - 1979. - 239(2023), 5 vom: 26. Sept., Seite 1584-1602 |
|---|---|
| 1. Verfasser: | |
| Weitere Verfasser: | , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2023
|
| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article Review Research Support, Non-U.S. Gov't embryo endosperm grain crop species phloem plasmodesmata seed coat sugar transporters mehr... |
| Zusammenfassung: | © 2023 The Authors. New Phytologist © 2023 New Phytologist Foundation. Sugar loading of developing seeds comprises a cohort of transport events that contribute to reproductive success and seed yield. Understanding these events is most advanced for grain crops (Brassicaceae, Fabaceae and Gramineae) and Arabidopsis. For these species, 75-80% of their final seed biomass is derived from phloem-imported sucrose. Sugar loading consecutively traverses three genomically distinct, and symplasmically isolated, seed domains: maternal pericarp/seed coat, filial endosperm and filial embryo. Sink status of each domain co-ordinately transitions from growth to storage. The latter is dominated by embryos (Brassicaceae and Fabaceae) or endosperms (Gramineae). Intradomain sugar transport occurs symplasmically through plasmodesmata. Interdomain sugar transport relies on plasma-membrane transporters operating in efflux (maternal and endosperm) or influx (endosperm and embryo) modes. Discussed is substantial progress made in identifying, and functionally evaluating, sugar symporters (STPs, SUTs or SUCs) and uniporters (SWEETs). These findings have underpinned a mechanistic understanding of seed loading. Less well researched are possible physical limitations imposed by hydraulic conductivities of differentiating protophloem and of subsequent plasmodesmal transport. The latter is coupled with sugar homeostasis within each domain mediated by sugar transporters. A similar conclusion is ascribed to fragmentary understanding of regulatory mechanisms integrating transport events with seed growth and storage |
|---|---|
| Beschreibung: | Date Completed 03.08.2023 Date Revised 03.08.2023 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/nph.19058 |