Transcriptional Regulation in Eukaryotes

A specific DNA sequence that allows the binding of regulatory proteins like transcription factors, enabling the regulation of gene expression.

DNA sequences that can be located far from the gene they regulate, influencing gene expression by increasing or decreasing transcription rates.

Proteins that bind to promoters and enhancers, influencing gene activity by recruiting RNA polymerase and modifying chromatin structure.

A complex of proteins involved in the initiation and regulation of transcription in eukaryotes.

Signal transduction pathways involve a series of steps that relay a signal from outside the cell to the nucleus, ultimately triggering changes in gene expression.

A type of transcription factor activated by cyclic AMP (cAMP), playing a crucial role in gene expression in response to various stimuli.

A class of transcription factors activated by the binding of specific hormones, like steroids, regulating a diverse array of genes.

A structural motif found in many nuclear hormone receptors, responsible for DNA binding and hormone recognition.

Small molecules that bind to receptors, initiating a cascade of events leading to gene activation.

Cellular processes that involve the packaging and organization of DNA within the nucleus, influencing gene expression.

Histones are proteins that package and order DNA into nucleosomes, the fundamental building blocks of chromatin. The core histone proteins are: H2A, H2B, H3, and H4. These proteins have a high proportion of positively charged basic amino acids, like lysine and arginine, which interact with the negatively charged phosphate backbone of DNA.

Post-translational modifications of histones are chemical changes that occur after a histone protein is synthesized. These modifications play a crucial role in regulating gene expression. Common modifications include:

Methylation involves adding a methyl group (-CH3) to lysine or histidine residues of histone proteins. It can lead to both gene activation and repression, depending on the specific site and the context. It also plays a role in DNA replication.

Acetylation involves the addition of an acetyl group (CH3CO2-) to lysine residues of histone proteins, primarily in the core histones. Acetylation is generally associated with gene activation, as it loosens the chromatin structure, making the DNA more accessible to transcription factors.

Phosphorylation involves adding a phosphate group (PO4-) to lysine residues of histone H1. It's linked to cell division, transcription, and chromatin structure. It can affect how tightly DNA is packed.

An enhancer is a DNA sequence that can be located thousands of base pairs away from a gene's promoter. It functions to increase the rate of transcription. Enhancers are generally orientation-independent and can work regardless of their position relative to the promoter.

A promoter is a DNA sequence located upstream of a gene, typically close to the transcription start site. It serves as a binding site for RNA polymerase and other transcription factors, which are necessary for the initiation of transcription.

Transcriptional stimulation is the process by which the rate of gene transcription is increased. It involves various factors and complexes that work together to initiate and enhance gene expression in a regulated manner.

A protein complex that helps organize DNA into chromatin, playing a key role in regulating gene expression.

The basic repeating unit of chromatin, composed of DNA wrapped around a core of histone proteins.

An enzyme that adds acetyl groups to histone tails, leading to a more relaxed chromatin structure that allows easier access for transcription.

A region of DNA that is more susceptible to digestion by DNase I, indicating an open chromatin structure associated with active gene expression.

A complex of proteins that mediates the interaction between transcription factors and RNA polymerase, facilitating the initiation of transcription.

A protein that binds to a transcription factor, acting as an intermediary to facilitate the binding of other proteins involved in the transcription process.

The addition of a 7-methylguanosine (m7G) cap to the 5' end of a pre-mRNA molecule.

The addition of a poly(A) tail, a string of adenine nucleotides, to the 3' end of a pre-mRNA molecule.

The process of removing non-coding introns from pre-mRNA and splicing together the remaining coding exons.

A sequence in pre-mRNA that signals where a poly(A) tail should be added.

A protein complex involved in polyadenylation.

The process of producing multiple mature mRNA transcripts from a single gene, generating diverse proteins with different functions.

Regions of pre-mRNA that are removed during splicing.

Regions of pre-mRNA that remain after splicing and are translated into proteins.

A specific DNA sequence within a gene that signals the start of an intron. It is recognized by splicing factors during pre-mRNA processing.

A specific DNA sequence within a gene that signals the end of an intron. It is recognized by splicing factors during pre-mRNA processing.

A conserved sequence within an intron that is crucial for the splicing process. It serves as a branch point for the formation of a lariat structure.

A complex of small nuclear ribonucleoproteins (snRNPs) and protein splicing factors that carries out the removal of introns from pre-mRNA.

The first step of splicing where the 5' splice site is cleaved and a lariat structure is formed at the branchpoint sequence.

The second step of splicing where the 3' splice site is cleaved, the intron is removed, and the exons are ligated together.

A process in which the introns within a pre-mRNA molecule are removed and exons are joined together to form a mature mRNA.

Small nuclear ribonucleoproteins, composed of snRNA and proteins, that are essential components of the spliceosome.

The sequence within a pre-mRNA molecule that marks the beginning of an intron.

The sequence within a pre-mRNA molecule that marks the end of an intron.

A non-coding RNA molecule that is involved in the splicing of pre-mRNA.

A type of RNA processing that adds a 5' cap to the 5' end of pre-mRNA.

A type of RNA processing that adds a poly(A) tail to the 3' end of pre-mRNA.