The Alternative Splicing Of Drosophila Melanogaster 14-3-3ξ Gene

Eukaryotic Pre-mRNAs always undergoes series of post-transcriptional modification in order to become functional mRNAs, including 5'cap processing,3'polyadenylation, RNA editing and alternative splicing et al. The alternative splicing of pre-mRNAs dramatically increases the diversity of proteins and the complexity of genes expression. A notable feature of eukaryotic pre-mRNA introns is the relatively high level of conservation of the primary sequences of 5'and 3'splice sites over a great range of organisms. The removal of introns from pre-mRNA transcripts and the concomitant ligation of exons is known as pre-mRNA splicing. It is a fundamental aspect of constitutive eukaryotic gene expression and an important level at which gene regulated. Alternative splicing takes positive roles in proteome extension, as well as conferring novel functions to macromolecules. Various types of alternative splicing patterns on regulatory aspect have drawn more and more attentions from scientists, especially their impact on tiny functional tuning through changing regional structure of biomolecules.Members of the 14-3-3 protein family form a group of highly conserved 30 kDa acidic proteins expressed in a wide range of organisms and tissues.14-3-3 is now established as a family of dimeric proteins that can modulate interaction between proteins. They are involved in cell signalling, regulation of cell cycle progression, intracellular trafficking/targeting, cytoskeletal structure and transcription. A specific repertoire of dimer formation may influence which of the 14-3-3 interacting proteins could be brought together. The regulation of interaction usually involves phosphorylation of the interacting protein and in some cases the phosphorylation of 14-3-3 isoforms themselves may modulate interaction.Mutually exclusive splicing is a type of alternative splicing which is strictly regulated. In this form, only one out of two or more mutually exclusive exons is included in the mature mRNA isoforms, the protein diversity increased by this way. We find that 14-3-3ξ, gene of Drosophila melanogaster has three mutually exclusive exons5a,5b and 5c. Comparative genome analysis revealed the built-in intronic elements for controlling mutually exclusive splicing of the 14-3-3ξpre-mRNA:two selector sequences and a docking sequencing, and they could be folded into well RNA secondary structure. In this study, we designed some mutant constructs to explore the mechanism of alternative splicing of D.melanogaster 14-3-3ξgene. Our data indicate that the sequence behind crossover of chimeric exon5b of 14-3-3ξhave influenced the alternative splicing.