Molecular changes associated with tuberisation in Solanum tuberosum. Differential expression of α‐tubulin isotypes

Abstract
Changes in gene expression that occur in the stolon tips of potato (Solanum tuberosum L.) cv. Record during tuberisation were investigated. Protein extracts from stolon tips at various stages in the tuberisation process were analysed by two‐dimensional gel electrophoresis. A number of quantitative and qualitative changes in polypeptide composition accompanied the very early stages of tuberisation. In vitro translation of RNA extracted from stolon tips also revealed quantitative and qualitative changes associated with tuberisation. Immunoblotting of protein extracts with monoclonal antibodies raised against α‐ and β‐tubulin showed quantitative changes in the relative level of β‐tubulin, but not α‐tubulin, as the stolon tips tuberised. Changes in the pattern of α‐tubulin isotype expression were shown to occur at early stages in the tuberisation process.