Pérez López, JesúsFeria Bourrellier, Ana BelénGandullo Tovar, Jacinto ManuelOsa Fernández, Clara de laJiménez Guerrero, IreneEchevarría, CristinaMonreal Hermoso, José AntonioGarcía-Mauriño Ruiz-Berdejo, Sofía2023-07-042023-07-042023Pérez López, J., Feria Bourrellier, A.B., Gandullo Tovar, J.M., Osa Fernández, C.d.l., Jiménez Guerrero, I., Echevarría, C.,...,García-Mauriño Ruiz-Berdejo, S. (2023). Silencing of SbPPCK1-3 Negatively Affects Development, Stress Responses and Productivity in Sorghum. Plants, 12 (13), 2426. https://doi.org/10.3390/plants12132426.2223-7747https://hdl.handle.net/11441/147697Phosphoenolpyruvate carboxylase (PEPC) plays central roles in photosynthesis, respiration, amino acid synthesis, and seed development. PEPC is regulated by different post-translational modifications. Between them, the phosphorylation by PEPC-kinase (PEPCk) is widely documented. In this work, we simultaneously silenced the three sorghum genes encoding PEPCk (SbPPCK1-3) by RNAi interference, obtaining 12 independent transgenic lines (Ppck1-12 lines), showing different degrees of SbPPCK1-3 silencing. Among them, two T2 homozygous lines (Ppck-2 and Ppck-4) were selected for further evaluation. Expression of SbPPCK1 was reduced by 65% and 83% in Ppck-2 and Ppck-4 illuminated leaves, respectively. Expression of SbPPCK2 was higher in roots and decreased by 50% in Ppck-2 and Ppck-4 in this tissue. Expression of SbPPCK3 was low and highly variable. Despite the incomplete gene silencing, it decreased the degree of phosphorylation of PEPC in illuminated leaves, P-deficient plants, and NaCl-treated plants. Both leaves and seeds of Ppck lines had altered metabolic profiles and a general decrease in amino acid content. In addition, Ppck lines showed delayed flowering, and 20% of Ppck-4 plants did not produce flowers at all. The total amount of seeds was lowered by 50% and 36% in Ppck-2 and Ppck-4 lines, respectively. The quality of seeds was lower in Ppck lines: lower amino acid content, including Lys, and higher phytate content. These data confirm the relevance of the phosphorylation of PEPC in sorghum development, stress responses, yield, and quality of seedsapplication/pdf20 p.engAtribución 4.0 Internacionalhttp://creativecommons.org/licenses/by/4.0/Phosphoenolpyruvate carboxylasePhosphoenolpyruvate carboxylase kinaseProtein phosphorylationSeed productionSeed qualitySorghum bicolorinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccesshttps://doi.org/10.3390/plants12132426