Isolation and characterisation of asparagus officinalis l. cDNA clones encoding two forms of ubiquitin mRNA

Abstract

A cDNA library constructed from the immature, rapidly developing tip region of spears of Asparagus officinalis plants was screened by hybridisation with a cDNA clone for a polyubiquitin mRNA from Antirrhinum majus. Two independent, positively hybridising cDNAs were obtained, and their nucleotide sequence determined. One clone (pTIP22) encodes a partial cDNA for a ubiquitinribosomal fusion mRNA and the other (pTIP24) a partial cDNA for a polyubiquitin mRNA. The abundance of transcripts corresponding to pTIP24 was relatively constant in a range of intact tissues but decreased following spear harvest. Investigations of mRNA abundance during spear development demonstrated that the changes detected were harvest-induced. Transcripts corresponding to pTIP22 were associated with regions of active cell development, and decreased in abundance following spear harvest. © 1993 The Royal Society of New Zealand.