Comparative Proteomics of Tuber Induction, Development and Maturation Reveal the Complexity of Tuberization Process in Potato (Solanum tuberosum L.)

Abstract

Tuberization in potato ( Solanum tuberosum L.) is a developmental process that serves a double function, as a storage organ and as a vegetative propagation system. It is a multistep, complex process and the underlying mechanisms governing these overlapping steps are not fully understood. To understand the molecular basis of tuberization in potato, a comparative proteomic approach has been applied to monitor differentially expressed proteins at different development stages using two-dimensional gel electrophoresis (2-DE). The differentially displayed proteomes revealed 219 protein spots that change their intensities more than 2.5-fold. The LC-ES-MS/MS analyses led to the identification of 97 differentially regulated proteins that include predicted and novel tuber-specific proteins. Nonhierarchical clustering revealed coexpression patterns of functionally similar proteins. The expression of reactive oxygen species catabolizing enzymes, viz., superoxide dismutase, ascorbate peroxidase and catalase, were induced by more than 2-fold indicating their possible role during the developmental transition from stolons into tubers. We demonstrate that nearly 100 proteins, some presumably associated with tuber cell differentiation, regulate diverse functions like protein biogenesis and storage, bioenergy and metabolism, and cell defense and rescue impinge on the complexity of tuber development in potato.

Hormonal regulation of tuber formation in potato plants

“…In the last few years, the changes in the expression of many hundreds of genes and proteins occurring during tuber induction, initiation, and development were demonstrated [66,67,102]. Possible relationship between hormone action and gene expression is ana lyzed.…”

Nitric Oxide Regulates DELLA Content and PIF Expression to Promote Photomorphogenesis in Arabidopsis

“…well-documented roles regulating the adaptation to changes in temperature (Allakhverdiev et al, 2008) or light (Li et al, 2009), conditions that regulate developmental processes like seed germination and seedling establishment (Bailly et al, 2008), hypocotyl elongation (Stavang et al, 2009), flowering (Ye et al, 2000), leaf senescence (Jing et al, 2008), and tuber formation (Agrawal et al, 2008). Among reactive species produced in plants in response to changes in their environment, NO has been the focus of increasing interest in recent years, since it participates in both defensive (Romero-Puertas et al, 2004;Wendehenne et al, 2004;Hong et al, 2008) and developmental (He et al, 2004;Ló pez-Bucio et al, 2006) processes.…”

From the model to the crop: genes controlling tuber formation in potato

“…Studies in this model species have established that a CO-FT regulatory pathway highly related to that controlling flowering time in Arabidopsis and rice plays also a prominent role in the control of tuber differentiation ( Figure 1). New genomic tools [46], in conjunction with gene expression [47,48] and comparative proteomic data [49], together with the forthcoming sequence of the full potato genome [50], should allow rapid identification of the potato homologs for candidate genes with a reported role in circadian clock progression and flowering time control in Arabidopsis and the analysis of their function in tuberization control. An important aspect that deserves further study is the differential regulation of CO function in SD plants compared to Arabidopsis.…”