18 - Gene regulation Flashcards
Differential gene expression
the expression of different genes by cells with the same genome
Histone acetylation
the addition of an acetyl group to an amino acid in a histone tail
DNA methylation
is a biological process where a small chemical group called a methyl group is added to the DNA molecule
Epigenetic inheritance
refers to the transmission of information from one generation to the next that affects gene expression without changing the underlying DNA sequence.
Enhancer
a segment of eukaryotic DNA containing multiple control elements, usually located far from the gene whose transcription it regulates
Promoter
a specific nucleotide sequence in the DNA of a gene that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place
Terminator
in bacteria, a sequence of nucleotides in DNA that marks the end of a gene and signals RNA polymerase to release the newly made RNA molecule and detach from the DNA
Proximal control elements
are DNA sequences located NEAR a gene that help regulate the gene’s activity.
distal control elements
are DNA sequences that regulate gene expression FROM A DISTANCE, sometimes thousands of base pairs AWAY from the gene they influence
Activators
a protein that binds to DNA and stimulates gene transcription. In prokaryotes, activators bind in or near the promoter; in eukaryotes, activators generally bind to control elements in enhancers
Transcription factors
a regulatory PROTEIN that binds to DNA and affects transcription of specific genes
DNA-bending protein
is a type of protein that binds to DNA and causes it to bend or loop. This bending can bring distant parts of the DNA closer together, which is important for regulating gene expression
RNA polymerase 2
is an ENZYME in eukaryotic cells that plays a crucial role in transcribing DNA into messenger RNA (mRNA).
Repressors
a PROTEIN that inhibits gene transcription. In prokaryotes, repressors bind to the DNA in or near the promoter. In eukaryotes, repressors may bind to control elements within enhancers, to activators, or to other proteins in a way that blocks activators from binding to DNA.
Alternative RNA splicing
is a process in eukaryotic cells that allows a single gene to produce multiple different proteins
Exon
a sequence within a primary transcript that REMAINS in the RNA after RNA processing; also refers to the region of DNA from which this sequence was transcribed.
Intron
a noncoding, intervening sequence within a primary transcript that is REMOVED from the transcript during RNA processing; also refers to the region of DNA from which this sequence was transcribed
microRNA
a small, single-stranded RNA molecule, generated from a double-stranded RNA precursor. The miRNA associates with one or more proteins in a complex that can degrade or prevent translation of an mRNA with a complementary sequence.
Ubiquitin
is a small REGULATORY PROTEIN found in almost all eukaryotic cells. Its primary role is to tag other proteins for degradation
Proteasome
is a complex structure in cells that functions like a RECYCLING CENTER for proteins. It breaks down proteins that are damaged, misfolded, or no longer needed into smaller pieces called peptides
