SEQUENCE-ANALYSIS OF A CDNA CONTAINING THE GAG AND PROT REGIONS OF THE SOYBEAN RETROVIRUS-LIKE ELEMENT, SIRE-1

SIRE-1 is a family of several hundred dispersed copies of a very large DNA element from Glycine max that has features characteristic of retr oviruses and retrotransposons. A 2.4 kb SIRE-1-specific fragment was r ecovered from a soybean cDNA library and sequenced. The sequence conta ins two ORFs. Theoretical translation of ORF1 produces a gag-prot-like polyprotein containing highly conserved motifs found in retroelement nucleocapsids (CX(2)CX(4)HX(4)C) and aspartic proteases (LDSG). The se cond ORF is foreshortened. The cDNA also contains nearly 200 bp of a p utative 5' LTR just upstream of a tRNA primer-binding site.