A cDNA library was constructed from apples (Malus ×domestica Borkh.) harvested 1 week after anthesis (WAA). Four cDNA clones differentially hybridized to cDNAs from fruit picked 1 WAA versus cDNAs from fruit harvested 8 WAA and flower buds. The mRNAs corresponding to these cDNA clones—pAFD101 through 104—accumulated in the early stages of apple development, with highest levels at 2 to 4 WAA. The mRNA of pAFD104 was detected only in fruit tissue, while mRNAs for the other three clones were expressed at various levels in a range of tissues. Sequence analysis showed that pAFD101 had high homology to genes encoding the translation elongation factor 1α (EF-1α); pAFD102 had homology to the β-subunit of translation initiation factor 2 (eIF-2β); pAFD104 showed strong similarity to a proline-rich protein and to auxin down-regulated genes; while pAFD103 had no significant homology to any sequences in the databases. Genomic Southern hybridization showed that genes corresponding to all four cDNAs were representatives of small gene families present in the apple genome.
Interplay of Methionine tRNAs with Translation Elongation Factor Tu and Translation Initiation Factor 2 inEscherichia coli
