RNA Rearrangements in the Spliceosome

Slides:



Advertisements
Similar presentations
Protein Synthesis. E. coli Ribosome -70S particle, MW ~2.5 x dissociable into small (30S) and large (50S) subunits -30S contains 16S RNA, 21 polypeptides.
Advertisements

Five Classes of Introns
LECTURE 17: RNA TRANSCRIPTION, PROCESSING, TURNOVER Levels of specific messenger RNAs can differ in different types of cells and at different times in.
Excision of Intron Sequences
Gene Expression Chapter Eleven. What is Gene Expression? When a gene is expressed – that gene’s protein product is made: 1.DNA is transcribed into RNA.
Summary of the steps leading from gene to protein in eucaryotes and bacteria. The final level of a protein in the cell depends on the efficiency of each.
Mol Cell.Mol Cell Sep 9. pii: S RNA-Seq Identifies an Extensive Network of Conserved Neural- Enriched Exons Regulated by nSR100 △ PSI: displaying.
13 and 15 October, 2004 Chapter 13 RNA Splicing (and some other important stuff)
1 Alternative Splicing. 2 Eukaryotic genes Splicing Mature mRNA.
Lecture 6 of Introduction to Molecular Biology 生理所 蔡少正
RNA splicing By xiao yi 生物学基地班
Outline  Introduction  The chemistry of RNA Splicing  The Splicing Machinery  Splicing Pathway  Alternative Splicing  Exon Shuffling  RNA Editing.
Figure 7.1 E. coli RNA polymerase. Figure 7.2 Sequences of E. coli promoters.
RNA processing. RNA species in cells RNA processing.
Discovery of Alternative Splicing
Molecular Biology of the Cell
Quiz on Wed March 14th covering only this review. Will be worth 30pts.
DNA REPLICATION MOLECULAR BIOLOGY – DNA replication, transcription.
6 domains, “Helical Wheel” Domain I contains binding sites for the 5’ exon (keeps the 5’ exon from floating away after the first splicing step) Consensus.
RNA Splicing Prokaryotic genes: the codon is immediately adjacent to another Eukaryotic genes: consists of blocks of coding sequences separated by noncoding.
Post-transcriptional Processing. Processing Events in Prokaryotes vs Eukaryotes.
Pre-mRNA Splicing Lecture 1 Douglas Black. Fig The most complex RNA processing reaction is pre-mRNA splicing. Most genes in metazoan (multicellular)
Molecular Biology Fourth Edition
Approaches Used to Study Protein Involvement in Splicing Biochemical Fractionation and Complementation - fractionate extract and assay each fraction for.
Posttranscriptional Modification
Drosophila Development  Each egg is surrounded by a chorion.  The anterior end has two filaments to allow oxygen to enter the cell.  Sperm enter through.
Splicing. Movie removed to simplify downloading. You can download the movie separately.
Transcription Packet #20 5/31/2016 2:49 AM1. Introduction  The process by which information encoded in DNA specifies the sequences of amino acids in.
Excision of Intron Sequences. Splicing  Removal of introns must be very precise.  Conserved sequences for removal of the introns of nuclear mRNA genes.
Exploring Alternative Splicing Features using Support Vector Machines Feature for Alternative Splicing Alternative splicing is a mechanism for generating.
Molecular Biology Fifth Edition
BIOCHEMISTRY REVIEW Overview of Biomolecules Chapter 12 Transcription.
Transcription … from DNA to RNA.
Transcription in Prokaryotic (Bacteria) The conversion of DNA into an RNA transcript requires an enzyme known as RNA polymerase RNA polymerase – Catalyzes.
Complexities of Gene Expression Cells have regulated, complex systems –Not all genes are expressed in every cell –Many genes are not expressed all of.
Today Elements of complex genomes Protein domains and exon shuffling
ALTERNATIVE SPLICING Examples of pathways ...
Post-transcriptional RNA Modifications Gene Expression Part 2.
RNA Components of Spliceosome Active Site. S. cerevisiae - 4 RNAs -~80 proteins 66% RNA H. sapiens -5 RNAs (~400 nt) proteins 5% RNA Complex RNA.
Exam #1 is T 2/17 in class (bring cheat sheet). Protein DNA is used to produce RNA and/or proteins, but not all genes are expressed at the same time or.
Splicing regulation in Trypanosoma brucei Sachin Kumar Gupta, Shai Carmi, Asher Pivko, Ilana Naboishchikov, Mark Katzenellenbogen, and Shulamit Michaeli.
Chapter 13 RNA splicing. Many eukaryotic genes are split. Exons are any region retained in a mature RNA. Introns are intervening sequences removed by.
HOW DO CELLS KNOW WHEN TO EXPRESS A GENE? DO NOW:.
TRANSCRIPTION (DNA → mRNA). Fig. 17-7a-2 Promoter Transcription unit DNA Start point RNA polymerase Initiation RNA transcript 5 5 Unwound.
Eukaryotic Gene Regulation
INTRODUCTION TO MOLECULAR BIOLOGY
Factors Involved In RNA synthesis and processing Presented by Md. Anower Hossen ID: MS in Biotechnology.
Chapter 14 Opener RNA Splicing (In Eukaryotes)
Gene Structure and Regulation. Gene Expression The expression of genetic information is one of the fundamental activities of all cells. Instruction stored.
The Exon Junction Complex
Exam #1 is T 9/23 in class (bring cheat sheet).
Exam #1 W 9/26 at 7-8:30pm in UTC 2.102A Review T 9/25 at 5pm in WRW 102 and in class 9/26.
Regulation of Gene Expression by Eukaryotes
Dr. Peter John M.Phil, PhD Atta-ur-Rahman School of Applied Biosciences (ASAB) National University of Sciences & Technology (NUST)
Peter John M.Phil, PhD Atta-ur-Rahman School of Applied Biosciences (ASAB) National University of Sciences & Technology (NUST)
Dr. Peter John M.Phil, PhD Atta-ur-Rahman School of Applied Biosciences (ASAB) National University of Sciences & Technology (NUST)
Transcription in Prokaryotic (Bacteria)
The Spliceosome: Design Principles of a Dynamic RNP Machine
RNA Splicing and Processing
Alternative Splicing— When Two’s a Crowd
Towards a Splicing Code
Control of splicing. Control of splicing. Cis acting elements, such as exon splicing enhancer sequences (ESE), exon splicing silencers (ESS), intron splicing.
Mechanisms and Consequences of Alternative Polyadenylation
(and some other important stuff)
Jonathan P Staley, Christine Guthrie  Cell 
Crossing the Exon Molecular Cell
Alternative Splicing: New Insights from Global Analyses
Myotonic Dystrophy Molecular Cell
Dynamic Integration of Splicing within Gene Regulatory Pathways
Splice isoforms of the JNK1, JNK2, and JNK3 proteins.
Presentation transcript:

RNA Rearrangements in the Spliceosome -extensive U4/U6 interaction is replaced with a U2/U6 structure -U1 displaced at 5’ splice site by U6

RNA Rearrangment at 5’ Splice Site

Why Splicing?

Why Splicing? -ancient or new? -functional units (W. Gilbert) -diversity of function, evolution -alternative splicing

Exon Shuffling

Sequence Conservation Within Introns 5’ Splice Site Yeast Human

Sequence Conservation Within Introns Branch Region 3’ Splice Site Yeast Human

Drosophila Doublesex (dsx) RNA

Tissue and Developmental Regulation

Alternative Splicing and Proteome Complexity Dscam 115 exons 20 constitutive, 95 alternatively spliced 38,016 possible proteins

Mechanisms of Alternative Splicing -activation/repression -intron sequences: splice sites, pyrimidine tract, branch region -exon sequences (purine rich enhancers)

Recall: Selection of 5’ Splice Site and Branch

SR Proteins -S100 extract is deficient in pre-mRNA splicing -S100 + SR splices -SR proteins are phosphoproteins (SRPK kinase) -human SC35, 24 C terminal SR repeats

RNA Recognition Motif (RRM) PTB RRM-3 Sxl RRM-1

Activation -downstream activation of 5’ splice site -adenovirus E1A, also Tra/Tra2 Mol. Cell. Biol. (1999) 19, 7347

“Enhancers”: -stimulate 5’ or 3’ splice site usage vs

“Enhancers”: -stimulate 5’ or 3’ splice site usage vs

“Enhancers”: -within exons -proximal to splice sites -conserved

Science 297, 1007 (2002)

Repression -formation of RNA secondary structure (blocking site access); relieved by ATP dependent helicases -binding of trans factors

Drosophila sxl Gene

sxl Regulation of Drosophila splicing -sxl competition with U2AF on dsx (also polypyrimidine tract binding protein -PTB; neuronal specific events)