Characterization of a cytokinin induced cDNA showing sequence homologies to hybrid proline (or glycine) rich proteins in Catharanthus roseus cell suspension cultures

Abstract In a preliminary screening of a cDNA library we isolated a cDNA that accumulates to high levels in cytokinin treated cells. The expression of the related transcript was induced after treatment with benzylaminopurine (BAP), zeatine and kinetine. Sequence analysis showed the presence of multiple initiation and stop codons and the absence of a long open reading frame (ORF). However, classic polyadenylation signals and poly A tail were found. Searching for nucleotide and amino acid similarities revealed a strong homology (up to 90%) with cDNAs corresponding to hybrid proline (or glycine)—rich proteins (HyPRP/HyGRP). A particular homology was found with a recently reported tobacco cDNA which encodes a novel glycine rich hydrophobic protein.