Expression Profiling of Cassava Storage Roots Reveals an Active Process of Glycolysis/Gluconeogenesis

• Published in: Journal of integrative plant biology 2011-03, Vol.53 (3), p.193-211
• Main Authors: Yang, Jun, An, Dong, Zhang, Peng
• Format: Article
• Language: English
• Subjects: Gluconeogenesis - genetics; Gluconeogenesis - physiology; Glycolysis - genetics; Glycolysis - physiology; Manihot - enzymology; Manihot - genetics; Manihot - metabolism; Plant Proteins - metabolism; Plant Roots - enzymology; Plant Roots - genetics; Plant Roots - metabolism; Polymerase Chain Reaction; 差异表达基因; 活动过程; 焦磷酸化酶; 糖酵解; 逆转录聚合酶链反应
• ISSN: 1672-9072; 1744-7909
• DOI: 10.1111/j.1744-7909.2010.01018.x

Mechanisms related to the development of cassava storage roots and starch accumulation remain largely unknown. To evaluate genome-wide expression patterns during tuberization, a 60 mer oligonucleotide microarray representing 20 840 cassawl genes was designed to identify differentially expressed transcripts in fibrous roots, developing storage roots and mature storage roots. Using a random variance model and the traditional twofold change method for statistical analysis, 912 and 3 386 upregulated and downregulated genes related to the three developmental phases were identified. Among 25 significantly changed pathways identified, glycolysis/gluconeogenesis was the most evident one. Rate-limiting enzymes were identified from each individual pathway, for example, enolase, L-lactate dehydrogenase and aldehyde dehydrogenase for glycolysis/gluconeogenesis, and ADP-glucose pyrophosphorylase, starch branching enzyme and glucan phosphorylase for sucrose and starch metabolism. This study revealed that dynamic changes in at least 16% of the total transcripts, including transcription fac- tors, oxidoreductases/transferases/hydrolases, hormone-related genes, and effectors of homeostasis. The reliability of these differentially expressed genes was verified by quantitative real-time reverse transcription-polymerase chain reaction. Tlhese studies should facilitate our understanding of the storage root formation and cassava improvement.