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Stachula, P.

Publications and source records attributed to Stachula, P..

2 recordsLinked to original sources

SnRK2.4 and SnRK2.10 redundantly control developmental leaf senescence by sustaining ABA production and signaling

Plants constantly and precisely control their growth by inducing distinct developmental programs to survive and produce high-quality offspring in the changing environment. The fine-tuning of the development according to endogenous and environmental signals requires exact intercellular signaling and a balanced response. Kinases of the Sucrose non-fermenting-1-Related protein Kinases type 2 (SnRK2s) family primarily take part in the response and adaptation to environmental stress factors. Notably, here we show that two ABA-non-activated SnRK2s, SnRK2.4 and SnRK2.10, are also activated in non-stress conditions in developmentally senescing leaves of Arabidopsis thaliana. Phenotypic, biochemical, and molecular analyses performed on single snrk2.4 or snrk2.10, and double snrk2.4/2.10 kinase mutants showed that SnRK2.4 and SnRK2.10, acting redundantly, promote developmental leaf senescence. Further, SnRK2.4 and SnRK2.10 enhance ABA accumulation in senescing leaves by inducing NCED2, one of key ABA biosynthesis-related genes. The two kinases induce developmental leaf senescence by modulating the expression of multiple ABA-responsive, osmotic stress, and senescence-related genes, such as the senescence master regulators ORE1, ORS1, WRKY33, WRKY75, and ANAC087. Furthermore, we show that SnRK2.4 and SnRK2.10 act upstream of MAPK signaling by enhancing the expression and activity of MAPKKK18, a senescence-inducing kinase. These results document a new regulatory function of SnRK2.4 and SnRK2.10: they are activated in Arabidopsis leaves in response to endogenous signals and redundantly induce developmental leaf senescence by stimulating ABA production and sustaining major ABA-dependent and -independent signaling pathways.

plant biology↗

Norway spruce deploys tissue specific canonical responses to acclimate to the cold

Cold acclimation in plants is a complex phenomenon involving numerous stress-responsive transcriptional and metabolic pathways. Existing gene expression studies have primarily addressed short-term cold acclimation responses in herbaceous plants, while few have focused on perennial evergreens, such as conifers, that survive extremely low temperatures during winter. To characterize the transcriptome changes during cold acclimation in Picea abies (L.) H. Karst (Norway spruce), we performed RNA-Sequencing analysis of needles and roots subjected to a chilling progression (5 {degrees}C) followed by 10 days at freezing temperature (-5 {degrees}C). Comparing gene expression responses of needles against Arabidopsis thaliana L. (Arabidopsis) leaves, our results showed that early transient inductions were observed in both species but the transcriptional response of Norway spruce was delayed. Our results indicate that, similar to herbaceous species, Norway spruce principally utilizes early response transcription factors (TFs) that belong to the APETALA 2/ethylene-responsive element binding factor (AP2/ERF) superfamily and NACs. However, unique to the Norway spruce response was a large group of TFs that mounted a late transcriptional response to low temperature. A predicted regulatory network analysis identified key conserved TFs, including a root-specific bHLH101 homolog and other members of the same family with a pervasive role in cold regulation, such as homologs of ICE1 and AKS3 and also homologs of the NAC (anac47 and anac28) and AP2/ERF superfamilies (DREB2 and ERF3), providing new functional insights into cold stress response strategies in Norway spruce. One sentence summaryNorway spruce shares elements of the cold regulon described in herbaceous species but has undescribed components that contribute to the cold tolerance of this evergreen coniferous species.

plant biology↗