The seed-specific heat shock factorA9regulates the depth of dormancy inMedicago truncatulaseeds viaABAsignalling

Author(s)

Zinsmeister, Julia ^{[1, 2]} ; Berriri, Souha ^[1] ; Basso, Denise Puntel ^{[3, 1]} ; Ly-Vu, Benoit ^[1] ; Dang, Thi-Thu ; Lalanne, David ^[4] ; Amaral da Silva, Edvaldo Aparecido ^[3] ; Leprince, Olivier ^[4] ; Buitink, Julia ^[4]

Affiliation

^[1] Univ Angers, Inst Agro, SFR 4207 QuaSaV, IRHS, UMR1345, INRAE, F-49071 Beaucouze - France

^[2] Ctr Res Agr Genom CRAG, Barcelona - Spain

^[3] Univ Estadual Paulista, Fac Ciencias Agron, Dept Prod Vegetal, Botucatu, SP - Brazil

^[4] Thi-Thu Dang, Univ Angers, Inst Agro, SFR 4207 QuaSaV, IRHS, UMR1345, INRAE, F-49071 Beaucouze - France

• Document type: Journal article
• Source: PLANT CELL AND ENVIRONMENT; v. 43, n. 10 AUG 2020.
• Web of Science Citations: 3

Abstract

During the later stages of seed maturation, two key adaptive traits are acquired that contribute to seed lifespan and dispersal, longevity and dormancy. The seed-specific heat shock transcription factor A9 is an important hub gene in the transcriptional network of late seed maturation. Here, we demonstrate that HSFA9 plays a role in thermotolerance rather than in ex situ seed conservation. Storage ofhsfa9seeds ofMedicago truncatulaand Arabidopsis had comparable lifespan at moderate storage relative humidity (RH), whereas at high RH,hsfa9seeds lost their viability much faster than wild type seeds. Furthermore, we show that inM.truncatula, Mthsfa9seeds acquired more dormancy during late maturation than wild type. Transient expression of MtHSFA9in hairy roots and transcriptome analysis of Mthsfa9Tnt1 insertion mutants identified a deregulation of genes involved in ABA biosynthesis, catabolism and signalling. Consistent with these results,Mthsfa9seeds exhibited increased ABA levels and higher sensitivity to ABA. These data suggest that in legumes,HSFA9acts as a negative regulator of the depth of seed dormancy during seed development via the modulation of hormonal balance. (AU)

• FAPESP's process: 17/50211-9 - Genetic and molecular basis of chlorophyll in seeds: a step forward to improve soybean adaptability to climate change
• Grantee: Edvaldo Aparecido Amaral da Silva
• Support Opportunities: Research Projects - Thematic Grants