Sequence and expression of potato U2 snRNA genes.
AUTOR(ES)
Waugh, R
RESUMO
Plant UsnRNA multigene families show a high degree of sequence variation among individual gene members. The potato U2snRNA gene family consists of between twenty-five and forty genes. Four potato U2snRNA gene variants have been isolated. Despite the sequence variation in coding and flanking regions, all maintain the conserved U2snRNA secondary structure and all contain the plant UsnRNA promoter elements: the upstream sequence element (USE) and TATA-like box in the -70 and -30 regions respectively. In RNase A/T1 protection analyses, one of the genes, PotU2-22, protected high levels of full length U2snRNA transcripts in potato leaf, stem, root and tuber RNA. Thus, PotU2-22 or genes with identical coding regions, are highly expressed in these potato organs and therefore represent a major subset of functional U2snRNA genes. Similar expression levels of the PotU2-22 sequence variant were also found in four genetically different potato cultivars and also in tobacco, a species closely related to potato, suggesting conservation of the coding regions of expressed U2snRNA genes. A second gene, PotU2-4, protected very low levels of full length transcripts while a third gene, PotU2-11, was not expressed in the potato organs analysed. The relative expression levels of the gene variants may reflect individual gene differences in, for example, the USE and TATA regulatory elements, or variations in gene copy number.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=333587Documentos Relacionados
- Nucleotide sequence and expression of a new Arabidopsis U2 snRNA gene.
- Nucleotide sequence of a pea U2 snRNA gene.
- Structure of U2 snRNA genes of Arabidopsis thaliana and their expression in electroporated plant protoplasts
- Both Oct-1 and Oct-2A contain domains which can activate the ubiquitously expressed U2 snRNA genes.
- Coiled Bodies and U2 snRNA Genes Adjacent to Coiled Bodies Are Enriched in Factors Required for snRNA Transcription