Phase change in Prunus avium: Differences between juvenile and mature shoots identified by 2-dimensional protein separation and in vitro translation of mRNA

Differences in protein content and translatable mRNA between shoot tips of juvenile and mature Prunus avium L. cv. Stella were analysed. Samples were taken from self-pollinated seedlings and rooted cuttings from the crown of the mature parent tree growing under the same conditions in a controlled environment cabinet, and directly from the branches of the parent tree in the field. 2-dimensional polyacrylamide gel electrophoresis profiles of a protein fraction enriched for membrane proteins and in vitro translation products of extracted messenger RNA were examined. Some proteins were found to differ in relative abundance in a phase-dependent manner. Comparison of in vitro translation products also revealed differences in the abundance of specific messenger RNA transcripts. A phase-dependent protein was purified from PAGE gels and N-terminal amino acid sequence data were obtained. This 12 kDa protein, which was expressed at higher levels in juvenile shoot tips, showed sequence homology with a 40 kDa subunit of the enzyme 5-aminolevulinic acid dehydratase (EC 4.2.1.24) from higher plants.