Bioinformatics Analysis Of 3 End Untranslated Region In Magnaporthe Grisea And Significantly Epressed Genes In Rice Endosperm

In this article,we analyzed the 3' end untranslated region sequences of Magnaporthe grisea using bioinformatics approaches.As a result,a model of the distribution of 3' end UTR cis-elements and their structures is generated.There are in total five types of controlling regions in this model:the cleavage site.the far upstream region,the near upstream region,the near downstream region and the far downstream region.The cis-elements in the far upstream region include T-rich,TG-rich and GA-rich elements: T-rich and A-rich elements were found as the main cis-elements in the near upstream region;the near downstream region mainly include T-rich.A-rich and TGAT-containing elements;while the main cis-elements in the far downstream region is T-rich elements,the frequency of which is relatively very low compared to other elements.Most of these elements can be found in mammals,plants and yeast,but is different with any model of these species.In addition,alternative polyadenylation is also studied,and more than one third genes in Magnaporthe grisea were found with 2 or more polyA sites,but no function-specificity or process-specificity was found for these genes.Rice endosperm plays a very important role in seedling germination and determines the qualities of rice grain.Although studies on specific gene categories in endosperm have been carried out,global view of gene expression at transcription level in rice endosperm is still limited.To gain a better understanding of the global and tissue specific gene expression profiles in rice endosperm,a cDNA library from rice endosperm of immature seeds was sequenced.A cDNA array was constructed based on the TUTs derived from EST assembling results and then hybridized with cDNAs from five different tissues or organs including endosperm,embryo,leaf.stem and root of rice.Significant redundancy.was found for genes encoding prolamin,glutelin. allergen,and starch synthesis proteins,accounting for～34%of the total ESTs obtained.The cDNA array revealed 87 significantly expressed genes in endosperm compared to the other 4 organs or tissues.These genes included 13 prolamin family proteins.17 glutelin family proteins.12 binding proteins,9 catalytic proteins and 4 ribosomal proteins,indicating a complicated biological processing in rice endosperm. In addition,northern verification of 1,4-alpha-glucan branching enzyme detected two isoforms in rice endosperm,the larger one of which only existed in endosperm.