Post-transcriptional regulation of a salt-inducible alfalfa gene encoding a putative chimeric proline-rich cell wall protein
✍ Scribed by Charles E. Deutch; Ilga Winicov
- Publisher
- Springer
- Year
- 1995
- Tongue
- English
- Weight
- 779 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0167-4412
No coin nor oath required. For personal study only.
✦ Synopsis
A cDNA previously shown to identify a salt-inducible root-specific transcript in Medicago sativa was used to screen an alfalfa library for the corresponding genomic sequence. One positive clone was recovered. The nucleotide sequence of a subclone contained a 329 bp 5' region upstream of the first ATG codon, a 1143 bp coding segment, and a 447 bp 3'-untranslated region interrupted by a single 475 bp intron.
Translation of the coding segment, which was designated MsPRP2, suggested it encodes a chimeric 40 569 Da cell wall protein with an amino-terminal signal sequence, a repetitive proline-rich sequence, and a cysteine-rich carboxyl-terminal sequence homologous to nonspecific lipid transfer proteins. The 3'-untranslated region of MsPRP2 contained a sequence similar to one found to destabilize mRNAs transcribed from the elicitor-regulated proline-rich protein gene PvPRP1. Transcription run-on experiments using nuclei from salt-sensitive and salt-tolerant alfalfa callus suggested that the accumulation of MsPRP2 transcripts in salt-tolerant alfalfa cells grown in the presence of salt is due primarly to increased m R N A stability. The MsPRP2 gene thus may be a useful model for studying post-transcriptional salt-