Eukaryotic Gene Regulation Overview

The process of controlling the lifespan of an mRNA molecule.

A sequence within an mRNA molecule that determines its stability.

A sequence within an mRNA molecule that targets it to a specific cellular compartment.

A sequence within an mRNA molecule that triggers its degradation.

The amount of time an mRNA molecule remains functional in a cell.

A protein that helps regulate muscle contraction by binding to actin filaments.

The process of producing different protein isoforms from a single gene by using different combinations of exons.

A protein that binds to calcium ions and regulates muscle contraction.

The process of regulating gene expression at the level of mRNA translation.

A mechanism where the protein product of a gene inhibits its own synthesis.

A sequence of four amino acids at the beginning of a protein that acts as a signal for regulatory factors to bind. This binding can control gene expression.

A process where a protein can alter the expression of a gene by affecting the stability or translation of its mRNA. This type of regulation occurs after the gene has been transcribed into mRNA but before it is translated into protein.

Short RNA molecules that don't code for proteins but play a crucial role in regulating gene expression. They can act as 'guides' to target specific mRNAs for degradation, influencing the production of proteins.

A comprehensive catalog of all known human genes, including protein-coding genes and non-coding RNAs.

A significant discovery in the post-genome era, researchers found that a large portion of the human genome is transcribed into RNA, even though only a small percentage of this RNA encodes for proteins.

Eukaryotes have a nucleus where DNA is stored, while prokaryotes lack a nucleus.

Eukaryotes can regulate gene expression at various stages from DNA to protein, providing fine-grained control. Prokaryotes have fewer levels of regulation.

The complete set of genes an organism possesses.

Different cell types utilize different sets of genes to produce specific proteins, despite having the same genome.

The process of converting DNA into RNA, the first step in gene expression.

The process of converting RNA into protein, the final step in gene expression.

A segment of DNA that encodes for a specific protein.

The protein responsible for carrying oxygen in the blood.

Changes in chromatin structure are essential for DNA repair, replication, recombination, and gene expression.

Specialized regions of DNA that initiate the process of transcription.

DNA sequences that enhance transcription but are located further away from the promoter.

The region of DNA immediately upstream of the gene where RNA polymerase binds to initiate transcription.

A specific DNA sequence often located upstream of the promoter that can influence transcription.

A DNA sequence rich in G and C bases that binds transcription factors and can influence transcription.

Point mutations within the promoter region can affect the efficiency of transcription.

Promoters are DNA sequences upstream of genes that control the initiation of transcription. They are recognized by RNA polymerase and other transcription factors to start the process of gene expression.

Many genes have more than one promoter, which allows for multiple transcription start sites and different versions of the same gene.

The control region of the SV40 virus, a small DNA virus, contains a promoter, enhancer, and origin of replication.

Thymidine kinase is an enzyme involved in DNA replication and repair. It's frequently used in gene cloning and gene therapy.

Mutations within specific promoter elements significantly affect the level of transcription. This indicates that these elements play a crucial role in determining the rate of gene expression.

A gene can have multiple promoters, each with its own transcription start site. This leads to different versions of the gene, which may be expressed in different tissues or at different times.

The dystrophin gene is an example of a gene with multiple alternative promoters. It is a large gene that produces different versions of the dystrophin protein, which are expressed in different tissues.

Eukaryotic cells use three main classes of RNA polymerases: RNA polymerase I (for ribosomal RNA), RNA polymerase II (for messenger RNA and small nuclear RNA), and RNA polymerase III (for transfer RNA and 5S ribosomal RNA).

Eukaryotic promoters have specific nucleotide sequences that recognize and bind specific transcription factors. These transcription factors are required for the initiation of transcription.

Transcription factors (TFs) are proteins that bind to DNA and regulate the rate of transcription. They act as molecular switches that turn genes on or off in response to various signals. They can be activators, which increase transcription, or repressors, which decrease transcription.

General transcription factors are required for the initiation of transcription in all eukaryotic genes. They bind to the promoter and recruit RNA polymerase to the transcription start site.

Enhancers are DNA sequences that can be located far from the genes they regulate. They can increase the rate of transcription by interacting with transcription factors and bending the DNA to bring them closer to the promoter.

Eukaryotes' control of gene expression involves a complex interplay of factors including chromatin remodeling, the assembly of the basal transcription complex, DNA methylation, and post-transcriptional regulation.

A four-stranded DNA structure that protrudes from the DNA double helix, forming when cytosine bases pair with each other.

These regions are enriched with i-motifs and play a crucial role in regulating gene activity.

I-motifs are not randomly scattered throughout the genome but instead concentrated in specific areas.

The discovery of i-motifs in living cells opened up new possibilities for studying how these structures influence gene regulation and cellular processes.

Over 50,000 i-motif sites have been discovered in the human genome, indicating their widespread presence and potential importance.

The unique structure and distribution of i-motifs suggest they might play a role in gene regulation and other cellular processes by interacting with proteins or DNA.

The field of i-motif research is rapidly expanding, with ongoing efforts to uncover their exact roles in cell function and potential applications in medicine.

I-motifs are fascinating examples of non-canonical DNA structures that challenge our understanding of DNA function and provide exciting avenues for future research.

Long noncoding RNAs (lncRNAs) are RNA molecules that do not code for proteins but play a crucial role in regulating gene expression. They are involved in various processes, including chromatin structure, gene silencing, and developmental pathways.

Natural antisense transcripts (NATs) are RNA molecules that are complementary to a specific mRNA transcript from the same gene. They can regulate the expression of their corresponding mRNA by inhibiting translation or promoting degradation.

Circular RNAs (circRNAs) are a class of noncoding RNAs that are circularized, meaning they lack free ends. They have various regulatory functions, including acting as sponges to sequester microRNAs or directly interacting with proteins.

MicroRNAs (miRNAs) are small noncoding RNAs that play a crucial role in gene regulation by binding to target mRNAs and inhibiting their translation or promoting their degradation.

Epigenetics refers to the study of heritable changes in gene expression that occur without alterations in the underlying DNA sequence. These changes are often mediated by modifications to the DNA itself or to the proteins that package DNA, called histones.

The 'ping-pong' model describes the interplay between small RNAs and chromatin structure. It explains how small RNAs can guide modifications to chromatin, ultimately affecting gene expression.

The idea that human genomic DNA is interspersed with i-motif structures suggests that these non-canonical structures are not merely rare anomalies but rather a widespread feature with potential regulatory roles.

The human genome is not only a blueprint for proteins but also a vast library of noncoding RNAs, which have emerged as crucial players in gene regulation. These RNAs, like microRNAs and long noncoding RNAs, influence gene activity in various ways, revealing the intricate complexity of the genome.