Contents
What is alternative splicing of transcripts?
Alternative splicing (AS) therefore is a process by which exons or portions of exons or noncoding regions within a pre-mRNA transcript are differentially joined or skipped, resulting in multiple protein isoforms being encoded by a single gene.
What is the mechanism of alternative splicing?
Alternative splicing is the process of selecting different combinations of splice sites within a messenger RNA precursor (pre-mRNA) to produce variably spliced mRNAs. These multiple mRNAs can encode proteins that vary in their sequence and activity, and yet arise from a single gene.
What are the different types of alternate splicing?
Five main types of alternative splicing events are depicted. (A) Constitutive splicing; (B) mutually exclusive exons; (C) cassette alternative exon; (D) alternative 3′ splice site; (E) alternative 5′ splice site; and (F) intron retention.
Where does alternative splicing occur?
These can be located in the intron itself (intronic splicing silencers, ISS) or in a neighboring exon (exonic splicing silencers, ESS). They vary in sequence, as well as in the types of proteins that bind to them.
What are factors that are involved in mRNA splicing?
They can be located in a wide range of genes, including those that generate proteins, ribosomal RNA (rRNA), and transfer RNA (tRNA). Within introns, a donor site (5′ end of the intron), a branch site (near the 3′ end of the intron) and an acceptor site (3′ end of the intron) are required for splicing.
What is the most common type of alternative splicing in animals?
There are numerous modes of alternative splicing observed, of which the most common is exon skipping. In this mode, a particular exon may be included in mRNAs under some conditions or in particular tissues, and omitted from the mRNA in others.
What are isoforms in terms of mRNA transcripts and proteins?
From Wikipedia, the free encyclopedia. Gene isoforms are mRNAs that are produced from the same locus but are different in their transcription start sites (TSSs), protein coding DNA sequences (CDSs) and/or untranslated regions (UTRs), potentially altering gene function.
What is the significance of alternative splicing?
The overall function of alternative splicing is to increase the diversity of the mRNA expressed from the genome. Due to the combinatorial control mechanisms that regulate alternative exon recognition, splicing programs coordinate the generation of mRNA isoforms from multiple genes.
How does alternative splicing contribute to transcriptome diversity?
Alternative splicing (AS) is a major contributor to transcriptome and proteome diversity. Evolutionary studies help to address questions that are fundamental to understanding this important process.
What is the purpose of alternative splicing in RNA?
What is Alternative Splicing. Alternative splicing is the biological process responsible for the production of variant mRNA molecules from a particular primary RNA transcript of a particular gene. That means; the expression of a single gene can result in multiple proteins with the help of alternative splicing.
Which is the world record holder for alternative splicing?
Since then, alternative splicing has been found to be ubiquitous in eukaryotes. The “record-holder” for alternative splicing is a D. melanogaster gene called Dscam, which could potentially have 38,016 splice variants.
How are alternative splicing events differ between humans and fruit flies?
Relative frequencies of types of alternative splicing events differ between humans and fruit flies. Five basic modes of alternative splicing are generally recognized. Exon skipping or cassette exon: in this case, an exon may be spliced out of the primary transcript or retained.