Aging later but faster: how StCDF1 regulates senescence in Solanum tuberosum

• Published in: The New phytologist Vol. 242; no. 6; pp. 2541 - 2554
• Main Authors: Shi, Li, Biolley, Laura, Shaikh, Maroof Ahmed, Vries, Michiel E., Mittmann, Sybille Ursula, Visser, Richard G. F., Prat, Salome, Bachem, Christian W. B.
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01-06-2024
• Subjects: Biological Transport; DNA sequencing; Efflux; Gene Expression Regulation, Plant; Gene sequencing; Genotypes; Leaves; Life cycle; Life cycles; Plant Leaves - genetics; Plant Leaves - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Senescence - genetics; Plant Tubers - genetics; Plant Tubers - growth & development; Plant Tubers - physiology; Plants, Genetically Modified; Potatoes; Saccharides; Senescence; Solanum tuberosum; Solanum tuberosum - genetics; Solanum tuberosum - growth & development; StCDF1; StORE1; Sugar; Sugars - metabolism; Time Factors; Transcription Factors - genetics; Transcription Factors - metabolism; tuberization; Water purification; senescence; StCDF1; StORE1; life cycle; tuberization; Solanum tuberosum
• ISSN: 0028-646X; 1469-8137; 1469-8137
• DOI: 10.1111/nph.19525

Summary
In potato, maturity is assessed by leaf senescence, which, in turn, affects yield and tuber quality traits. Previously, we showed that the CYCLING DOF FACTOR1 (StCDF1) locus controls leaf maturity in addition to the timing of tuberization. Here, we provide evidence that StCDF1 controls senescence onset separately from senescence progression and the total life cycle duration.
We used molecular–biological approaches (DNA‐Affinity Purification Sequencing) to identify a direct downstream target of StCDF1, named ORESARA1 (StORE1S02), which is a NAC transcription factor acting as a positive senescence regulator.
By overexpressing StORE1S02 in the long life cycle genotype, early onset of senescence was shown, but the total life cycle remained long. At the same time, StORE1S02 knockdown lines have a delayed senescence onset. Furthermore, we show that StORE1 proteins play an indirect role in sugar transport from source to sink by regulating expression of SWEET sugar efflux transporters during leaf senescence.
This study clarifies the important link between tuber formation and senescence and provides insight into the molecular regulatory network of potato leaf senescence onset. We propose a complex role of StCDF1 in the regulation of potato plant senescence.
See also the Commentary on this article by Tai, 242: 2385–2387.