Spliceosome

Differential alternative splicing human tissue network analysis of GUK1 Result Figure 4.12: Visualisation of alternative splicing gene GUK1 in human tissues. Differential alternative splicing genes between two different tissues comparison were shown on a different visualisation platform and tools in comparison with network analysis. (A) rMATS analysis. Histogram shows inclusion level ψ, per sample for each tissue comparisons. In this case, only exon 3 found as statistically alternative splicing significance of skipped exon (SE) in both tissue comparisons; heart vs. liver and brain vs. liver. The inclusion level in the heart is 0.9 and 0.35 in the liver for tissue comparison heart vs. liver; while inclusion level in the brain is 0.83 and 0.28 in the liver for tissue comparison brain vs. liver. (B) Vials – visualising alternative splicing of genes. Data shows here is from the Illumina BodyMap 2.0. There are three views which are junction view, isoform abundance view and expression view. For each row in the isoform abundance view represent a particular isoform. Dark bar represents the exon that is included whilst the greyed out area represents the full spectrum of that exon’s splicing. A dot plots showing abundance for each tissue and for junction view show the junction reads. Dot plots show the abundance of junction support. Three tissues of brain, heart and liver were selected and multiple dot plots shown to allow comparison between these tissues. Different tissues show…

A. Eukaryotic cells store their genetic information in chromosomes made of DNA. This DNA is copied during interphase of the cell cycle. Replication is semiconservative, meaning one strand of the replicated DNA would be from the original molecule and one would be new. The parental strands serve as templates for the new strands. Replication can begin when helicase breaks the hydrogen bonds responsible for holding the two complementary strands together, ultimately causing the molecule to…

portions of a gene that do not code for amino acids, while exons do code for amino acids and contribute to the production of proteins (ghr intron). In the cells of plants and animals, most gene sequences are broken up by introns, which lay in between the expressed regions, exons. During protein synthesis, non-coding sequences of DNA are removed from mature messenger RNA prior to translation. DNA that was first transcribed to mRNA contain introns that are removed, or spliced, out of the messenger…

transcription factors also help terminating transcription. RNA transcripts must go through these processing steps to become mature mRNAs in order to leave the nucleus. During initiation, an enzyme attaches a 5’ cap to the first base in the transcript. This modified version of a guanine (G) nucleotide makes it more stable and protecting it from breaking down, protecting the mRNA produced. At the 3’ end of the transcript a long sequence of adenine (A) nucleotides are attached, called the poly-A…

thereby causes a mixture of the recombinant plasmids and the plasmids that do not contain the insert. To signify which ones have the inserted DNA, the blue-white screening technique must be used. This method presents the DNA that have been inserted into the plasmid which interrupts the lacZ gene, thereby preventing the α peptide from being produced. As a result, bacteria that have been transformed with recombinant plasmids are not able to break down X-Gal, like their counterparts and thus appear…

monocistronic mRNA molecules, meaning that the molecule will only code for cistron, and henceforth one protein. Conversely, Prokaryotic mRNA is polycistronic. This means that one mRNA molecule codes for multiple cistrons, resulting in the production of many proteins upon translation. Proteins produced from this polycistronic mRNA will likely have related function, for example each cistron may code for the subunits of the quaternary structure of a globular protein. Eukaryotes contain non coding…

replaces thymine. Had this DNA been in a eukaryotic cell, the process would not have been quite so simple. At termination, there would have been a polyadenylation signal sequence. About 10-35 nucleotides later, the RNA would be cut loose and transcription would end. In a eukaryote, the process wouldn’t have ended yet. Now, it would be time for RNA processing, the modification of pre-mRNA, also known as the primary transcript, before it is sent out into the cytoplasm. First, a modified…

molecule, the RNA goes through another phase before maturation. Transcription is only the first step in a sequence of reactions that consist of the covalent alteration of both ends of the RNA and the deletion of intron sequences that are deleted from the center of the RNA transcript by the process of RNA splicing. According to the textbook “Biology”, particles called small nuclear ribonucleoprotein particles abbreviated as snRNPs (pronounced “snurps”) contain snRNA that networks with the 5’ end…

Q1. Explain segmental trans-splicing (STS) and mention a long gene 8 kb or more, this strategy could be used for. A1. Segmental trans-splicing concept is similar to that of trans-splicing, where exons of two different gene fragments are joined together. However, in STS it can be used to target gene sequences that are too large for a viral vector genetic capacity; for example the von Willbrand factor gene (8.6 kb) or the muscular dystrophy gene (11.0 kb). In STS a 5’exon of the gene is delivered…

transcription is termination. Termination occurs when RNA polymerase reaches the terminator. The terminator is a DNA sequence that is read by RNA polymerase and signals the end of transcription. After the terminator sequence is read the RNA polymerase and the mRNA detach from the DNA. Even though an mRNA has been transcribed from a DNA sequence, it is not ready to be exported to the cytoplasm and translated. The mRNA must undergo mRNA splicing. An m RNA contains introns and exons. The exons…