The Unusual Acid-Accumulating Behavior during Ripening of Cherimoya (Annona cherimola Mill.) is Linked to Changes in Transcription and Enzyme Activity Related to Citric and Malic Acid Metabolism.
Cherimoya (Annona cherimola Mill.) is a subtropical fruit characterized by a significant increase in organic acid levels during ripening, making it an interesting model for studying the relationship between acidity and fruit flavor. In this work, we focused on understanding the balance between the concentration of organic acids and the gene expression and activity of enzymes involved in the synthesis and degradation of these metabolites during the development and ripening of cherimoya cv. "Concha Lisa". Our results showed an early accumulation of citric acid and other changes associated with the accumulation of transcripts encoding citrate catabolism enzymes. During ripening, a 2-fold increase in malic acid and a 6-fold increase in citric acid were detected. By comparing the contents of these compounds with gene expression and enzymatic activity levels, we determined that cytoplasmic NAD-dependent malate dehydrogenase (cyNAD-MDH) and mitochondrial citrate synthase (mCS) play important regulatory roles in the malic and citric acid biosynthetic pathways.
Instituto de Investigaciones Agropecuarias, INIA La Platina, Santa Rosa 11610, Santiago 8831314, Chile. maugonzalez@inia.cl.
Mauricio
M
González-Agüero
Facultad Ciencias Biológicas, Escuela de Ingeniería en Biotecnología, Universidad Andrés Bello, República 217, Santiago 8370146, Chile. ltejerinapardo@gmail.com.
Luis
L
Tejerina Pardo
Instituto de Investigaciones Agropecuarias, INIA La Platina, Santa Rosa 11610, Santiago 8831314, Chile. sofizamudio@gmail.com.
María Sofía
MS
Zamudio
Instituto de Investigaciones Agropecuarias, INIA La Platina, Santa Rosa 11610, Santiago 8831314, Chile. cdcontr1@uc.cl.
Carolina
C
Contreras
Facultad de Agronomía, Pontificia Universidad Católica de Valparaíso, Calle San Francisco s/n, Casilla 4-D, Quillota 2260000, Chile. pundurra@ucv.cl.
Pedro
P
Undurraga
Instituto de Investigaciones Agropecuarias, INIA La Platina, Santa Rosa 11610, Santiago 8831314, Chile. bdefilip@inia.cl.
Bruno G
BG
Defilippi
D000144:Acids, Acyclic / Q000378:metabolism*; D031041:Annona / Q000235:genetics / Q000502:physiology*; D019343:Citric Acid / Q000378:metabolism; D018744:DNA, Plant / Q000032:analysis; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D008291:Malate Dehydrogenase / Q000235:genetics*; D008293:Malates / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D010940:Plant Proteins / Q000235:genetics; D017422:Sequence Analysis, DNA
D000144:Acids, Acyclic; D018744:DNA, Plant; D008293:Malates; D010940:Plant Proteins; D019343:Citric Acid; C030298:malic acid; D008291:Malate Dehydrogenase
Annona cherimola; gene expression; organic acids