Conifer VNDs as Redox-Sensitive Regulators of Secondary Cell Wall Formation
Aleksandra Liszka (Poland)1 2; Sarah Pfaff (United States)3; Mateusz Dulski (Poland)4; Dariusz Latowski (Poland)5; Artur StoĊ‚owski (Poland)6;
1 - Jagiellonian University, Doctoral School of Exact and Natural Sciences, Krakow, Poland; 2 - Jagiellonian University, Faculty of Faculty of Biochemistry, Biophysics and Biotechnology, Department of Plant Biotechnology, Krakow, Poland; 3 - Pennsylvania State University, Department of Biology, University Park, USA; 4 - University of Silesia, Faculty of Science and Technology, Institute of Materials Science and Engineering, Chorzow, Poland; 5 - Jagiellonian University, Faculty of Faculty of Biochemistry, Biophysics and Biotechnology, Department of Plant Physiology, Krakow, Poland; 6 - AsterWorks, Kalwaria Zebrzydowska, Poland;
Keywords: Secondary cell wall; VND transcription factors; Redox;
Abstract Topics: Theme 6: Lignin and Secondary Cell Wall Formation
Type of Presentation: Poster

Abstract text: The composition and architecture of plant secondary cell walls (SCW) vary across species and tissues. For instance, in conifer wood, earlywood and latewood display distinct anatomical and biochemical features. We hypothesized that VND (VASCULAR-RELATED NAC-DOMAIN) transcription factors contribute to these differences in SCW formation. We confirmed transcription factor activity in Picea abies VND (PaVND) homologs. Biochemical, spectroscopic, and microscopic analyses, revealed their different role in shaping SCW composition and arragement. Gene expression profiling showed that overexpression of PaVNDs upregulated SCW-related genes, with gene target selection facilitated by our custom BLASTnBRUSH software. Moreover, these experiments suggested that individual PaVNDs contribute to SCW deposition to different extents. Experiments under varying light conditions revealed differential expression of PaVND genes, indicating light-dependent transcriptional regulation of xylogenesis. Given that light conditions affect oxidative stress, we examined redox regulation of PaVNDs, pinpointing key cysteines. Redox-altering factors were found to influence both PaVND activity and their interactions, highlighting an additional regulatory layer in SCW formation. Finally, we attempted to establish an SCW induction system in gymnosperm protoplasts to create a new model for xylogenesis studies and explore evolutionary aspects of SCW formation in conifers, including responses to redox stress.

Supported by National Science Centre Poland, PRELUDIUM22(2023/49/N/NZ3/03521).