Repositorium
Impaired phloem loading in zmsweet13a,b,c sucrose transporter triple knock-out mutants in Zea mays
bearbeiten
279
Typ / Jahr
Journal Article / 2018
Autoren
Bezrutczyk, Margaret; Hartwig, Thomas; Horschman, Marc; Char, Si Nian; Yang, Jinliang; Yang, Bing; Frommer, Wolf B.; Sosso, Davide
Abstract
Crop yield depends on efficient allocation of sucrose from leaves to seeds. In Arabidopsis, phloem loading is mediated by a combination of SWEET sucrose effluxers and subsequent uptake by SUT1/SUC2 sucrose/H+ symporters. ZmSUT1 is essential for carbon allocation in maize, but the relative contribution to apoplasmic phloem loading and retrieval of sucrose leaking from the translocation path is not known.
Here we analysed the contribution of SWEETs to phloem loading in maize.
We identified three leaf-expressed SWEET sucrose transporters as key components of apoplasmic phloem loading in Zea mays L. ZmSWEET13 paralogues (a, b, c) are among the most highly expressed genes in the leaf vasculature. Genome-edited triple knock-out mutants were severely stunted. Photosynthesis of mutants was impaired and leaves accumulated high levels of soluble sugars and starch. RNA-seq revealed profound transcriptional deregulation of genes associated with photosynthesis and carbohydrate metabolism. Genome-wide association study (GWAS) analyses may indicate that variability in ZmSWEET13s correlates with agronomical traits, especifically flowering time and leaf angle.
This work provides support for cooperation of three ZmSWEET13s with ZmSUT1 in phloem loading in Z. mays.
Keywords
Corn; efflux; export; leaf; maize; phloem loading; port.; sucrose; trans-; (Zea mays)
Periodical
New Phytol (New Phytologist)
Periodical Number
2
Page range
594–603
Volume
218
DOI
10.1111/nph.15021
Techniques
ID | Corresponding Author Country |
Plant Species | GE Technique Sequence Identifier |
Trait Type of Alteration |
Progress in Research Key Topic |
---|---|---|---|---|---|
671 |
Frommer, Wolf W. Germany; USA |
Zea mays |
CRISPR/Cas9 SWEET13 |
Key component of apoplasmic phloem loading SDN1 |
Basic research Basic research |