Structure of U2 small nuclear RNA genes of rice genome

Three new U2 small nuclear RNA (U2snRNA) genes from rice ( Oryza sativa) were isolated and sequenced. The upstream sequence elements, TATA elements, monocot-specific promoter elements and the conserved four-stem-loop secondary structure shared by all plant snRNA genes were identified The rice U2snRNA genes are shown to be present as a multi - gene family in the genome. The homology of the rice U2enRNA genes is high, with the minimum of 80%. Two pairs of the U2snRNA genes with the same transcriptional direction are found to be linked. One pseudogene in rice was firstly discovered.