Abstract
A U1-snRNP—specific 70K (U1-70K) protein is intricately involved in both constitutive and alternative splicing of pre-mRNAs. Here, we report cDNA and cognate genomic sequences of the U1-70K gene of maize and rice. The maize and rice U1-70K genes bear strong similarity to the Arabidopsis gene and each encode three transcripts in roots and shoots. Alternative splicing produces two transcripts from each gene in addition to the mRNA encoding the wild type protein. In both cases, selective inclusion of intron 6 or utilization of a cryptic donor site within intron 6 sequence generates the two alternatively spliced transcripts. This evolutionary conservation of splicing patterns between different plant species suggests an important biological function for alternative splicing in the expression of U1-70K gene.
Acknowledgements
We thank Drs Julia Bailey-Serres and Jill Zeilstra-Ryalls for their helpful discussion and critically reviewing the earlier version of this manuscript. We also thank Dr Gabrielle Stryker for posting supplemental data on the web. The work was supported by NSF (USA) grant 0514759 to SL and the Research Excellence Fund, Oakland University.