What determines the composition of the phloem sap? Is there any selectivity filter for macromolecules entering the phloem sieve elements?
Copyright © 2020. Published by Elsevier Masson SAS.
| Publié dans: | Plant physiology and biochemistry : PPB. - 1991. - 151(2020) vom: 05. Juni, Seite 284-291 |
|---|---|
| Auteur principal: | |
| Autres auteurs: | |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2020
|
| Accès à la collection: | Plant physiology and biochemistry : PPB |
| Sujets: | Journal Article Review Long distance signaling Phloem mobility Plasmodesmal transport Sieve element proteins |
| Résumé: | Copyright © 2020. Published by Elsevier Masson SAS. In view of recent findings, it is still a matter of debate whether the composition of the phloem sap of higher plants is specific and based on a plasmodesmal selectivity filter for macromolecular transport, or whether simply related to size, abundance and half-life of the macromolecules within the phloem sap. A range of reports indicates specific function of phloem-mobile signaling molecules such as the florigen making it indispensable to discriminate specific macromolecules entering the phloem from others which cannot cross this selectivity filter. Nevertheless, several findings have discussed for a non-selective transport via plasmodesmata, or contamination of the phloem sap by degradation products coming from immature still developing young sieve elements undergoing differentiation. Here, we discuss several possibilities, and raise the question how selectivity of the phloem sap composition could be achieved thereby focusing on mobility and dynamics of sucrose transporter mRNA and proteins |
|---|---|
| Description: | Date Completed 19.08.2020 Date Revised 30.09.2020 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1873-2690 |
| DOI: | 10.1016/j.plaphy.2020.03.023 |