UTR motifs and microRNA analysis 曾大千助理教授 10/28/2008
UTR motifs and microRNA analysis 曾 大 千 助 理 教 授 10/28/2008
DNA 500000090K88 Replication ↓Information叶 DNA duplicates DNA Information 2O不 RNA synthesis RNA mRNA nucleus cytoplasm nuclear envelope Translation Protein synthesis Protein Protein The Central Dogma of Molecular Biologry
RNA DNA Ribonucleic acid Deoxyribonucleic acid
TABLE 6-I Principal Types of RNAs Produced in Cells TYPE OF RNA FUNCTION mRNAs messenger RNAs,code for proteins rRNAS ribosomal RNAs,form the basic structure of the ribosome and catalyze protein synthesis tRNAs transfer RNAs,central to protein synthesis as adaptors between mRNA and amino acids snRNAs small nuclear RNAs,function in a variety of nuclear processes,including the splicing of pre-mRNA snoRNAs small nucleolar RNAs,used to process and chemically modify rRNAs Other noncoding function in diverse cellular processes,including RNAs telomere synthesis,X-chromosome inactivation, and the transport of proteins into the ER
mRNA synthesis and processing (A)EUCARYOTES (B)PROCARYOTES DNA nucleus TRANSCRIPTION RNA DNA TRANSLATION gene TRANSCRIPTION 0 hnRNA:heterogeneous RNA cap nuclear RNA,nuclear Ca■=■■■AAM precursor of mRNA RNA SPLICING mRNA AAAA EXPORT 5'Capping mRNA AAAA Pre-mRNA splicing TRANSLATION protein ·3'polyadenylation
mRNA synthesis and processing hnRNA: heterogeneous nuclear RNA, nuclear precursor of mRNA • 5’ Capping • Pre-mRNA splicing • 3’ polyadenylation
Nucleus Cytosol mRNA turnover control TATA box 4G) mRNA PABP AAAAAAAAAA mRNA transport and localization control Protein Transcriptional RNA processing control Control Translational Splicing,5'-capping control 3'-polyadenylation
TATA box Pol II TF Nucleus Cytosol Transcriptional control RNA processing Control Splicing, 5’-capping 3’-polyadenylation mRNA transport and localization control Protein mRNA turnover control Translational control AAAAAAAAAA PABP 4E 4G mRNA
Transcription and post-transcription mechanism coordinative regulate the gene expression level (b)Up (c)Up (d)Up (e)Up (b)Down (c)Down (d)Down (e)Down TRENDS n Genetics
Transcription and post-transcription mechanism coordinative regulate the gene expression level
Translational control Subcellular localization Stability Hairpin IRES Polyadenylation m7© Antisense RNA UORF Coding sequence3 -5 0AAA一 Interacting Protein protein complex 5 UTR 3UTR GB.c
SUTR ORF ■b■b B a■ 3 cc d Figure 2.The Post-transcriptional Operon/Regulon model.Monocistronic mRNAs,each containing multiple 5'or 3'UTR elements all regulatory RNAs that assis sthat encode f bacteria which are collinear with the genes in operons on the DNA.These mechanisms provide combinatorial regulation of the genetic information per se,and the evolution of multifunctionality among eukaryotic proteins.For example,the occupation of a UTR element by one RBP or micro RNA may preclude adjacent UTR elements from binding other factors.Thereby,each mRNA may have several fates or functions depending on what proportion of the mRNA is occupied within a specific mRNP.Reprinted from Mol Cell 9:1161,with permission of the publisher
Translation and mRNA stability Transferrin receptor:uptaked the iron into mammalian cell.When iron is scarce, synthesis of the transferrin receptor is stimulaed. Ferritin:an iron-storage protein.The protein synthesis is selectively stimulated in the presence of iron. Iron-response element:IRE Iron-response element-binding protein: binding with iron will lose the activity to bind with IRE
Translation and mRNA stability ➢ Transferrin receptor: uptaked the iron into mammalian cell. When iron is scarce, synthesis of the transferrin receptor is stimulaed. ➢ Ferritin: an iron-storage protein. The protein synthesis is selectively stimulated in the presence of iron. ➢ Iron-response element:IRE ➢ Iron-response element-binding protein: binding with iron will lose the activity to bind with IRE