RNA Transcription and Initiation

Proteins that bind to specific DNA sequences and regulate gene expression.

The coiling of DNA upon itself, creating tension.

Tension in DNA caused by supercoiling.

Increase in the level of gene expression or protein production.

Decrease in the level of gene expression or protein production.

A mutation that results in a gene or protein having a new or enhanced function

A mutation that results in a gene or protein having reduced or no function.

The way DNA and associated proteins (histones) are organized within the nucleus.

TFIID is a general transcription factor that binds to the core promoter. It has a TBP subunit that recognizes the TATA box and TAF subunits that recognize other DNA sequences near the transcription start point to regulate DNA binding by TBP.

TBP subunit of TFIID binds and recognizes TATA box, a crucial promoter DNA element.

TFIIB is a general transcription factor correctly positioning RNA polymerase at the start site of transcription by binding to the BRE promoter element.

TFIIH unwinds DNA at the transcription start point, phosphorylates RNA polymerase for release & starts transcription

A set of proteins, including TFIID, TFIIB, TFIIF, TFIIE, and TFIIH, essential for RNA polymerase binding and initiation.

A DNA region, often far from transcription start site, that boosts transcriptional activity.

A region in a gene's regulatory region where RNA polymerase binds to initiate transcription.

TFIIF stabilizes RNA polymerase's interaction with TBP & TFIIB, attracting other factors like TFIIE for initiation

A factor that increases transcription of a gene, with parts that recognize and bind to specific DNA sequences.

TFIIE attracts and regulates TFIIH, crucial for transcription initiation.

Different protein combinations (isoforms) produced from a single gene.

Introns, non-coding gene segments, can have regulatory elements like enhancers/silencers, affecting gene expression.

Intronic enhancers control 'when' and 'where' genes are expressed, like muscle-specific myosin genes.

Introns create space for mutations without harming protein-coding sequences, aiding gene evolution.

Introns facilitate the evolution of new genes via combining exons from different genes.

Introns play a part in creating additional gene copies.

Introns act as a buffer against harmful mutations for important exons.

Introns can create small RNA molecules like miRNAs & snRNAs, regulating gene expression.

Introns contain regulatory elements that can influence how genes work

Intron-based regulatory elements can alter how tightly DNA is packaged, which also affects gene expression.

A process in which introns are removed from pre-mRNA, and exons are joined together to form mature mRNA. It involves a complex machinery called the spliceosome.

The spliceosome is composed of snRNAs (small nuclear RNAs) and proteins, forming a ribonucleoprotein complex.

The junction between an intron and the upstream exon. This is where the first transesterification reaction occurs, breaking the bond between the intron and the exon.

The junction between the intron and the downstream exon. This is where the second transesterification reaction occurs, joining the exons together.

The process of removing introns from pre-mRNA. This occurs during the splicing process.

A loop-shaped intermediate formed during splicing. The intron is looped and covalently linked to itself through a 2'-5' bond. It then forms a structure resembling a lariat (noose).

A type of splicing that occurs in some organisms, particularly in mitochondria, chloroplasts, and some bacteria. It is characterized by a distinct structure and a self-splicing mechanism.

Introns play a role in forming loops in the DNA structure, influencing how genes are accessed by proteins called transcription factors. These loops help organize the DNA inside the nucleus.

Introns are involved in the formation of 'topologically associating domains' (TADs), which are distinct regions of DNA with their own organizational structure within the nucleus. These TADs help keep related genes together.

These are proteins that bind to specific sequences within introns and help organize the DNA structure. They are critical for creating the loops and TADs.

This specific sequence of DNA letters is often found within introns and serves as a binding site for the CTCF protein. This helps establish distinct boundaries within the DNA structure.

This is a type of alternative splicing where an entire exon is removed from the final mRNA transcript. This is the most common kind of alternative splicing.

This type of splicing allows cells to choose only one out of two or more adjacent exons. This creates different protein versions with different functions.

During splicing, the machinery can choose between different starting points within an intron, making slightly different versions of the final mRNA.

Similar to the 5' splice site, the splicing machinery can choose different ending points within an intron, creating slightly different mRNA versions.

In this unusual splicing event, an entire intron is kept within the final mRNA transcript. This can lead to a non-functional protein or have other consequences.

Genes can have multiple start points, or promoters, which can lead to different versions of the mRNA with different 5' untranslated regions (UTRs).