Transcription
This process involves producing RNA from a DNA template.
What is transcription?
This process in eukaryotic RNA processing allows for the production of multiple mRNA variants from a single gene.
These are the three binding sites found on a ribosome.
What are the A (aminoacyl), P (peptidyl), and E (exit) sites?
In the lac operon, this protein binds to the operator in the absence of lactose, preventing transcription of the operon's genes, but is inactivated when lactose is present, allowing gene expression."
What is the lac repressor (LacI)?
This domain of RNA Pol II plays a crucial role in eukaryotic RNA processing.
What is the C-terminal domain (CTD)?
These are the two core elements of a typical prokaryotic promoter in E. coli.
What are the -35 region and the -10 (Pribnow) box?
This term refers to the addition of a string of adenine nucleotides to the 3' end of an mRNA molecule.
What is polyadenylation?
his modified form of methionine initiates protein synthesis in prokaryotes.
What is N-formylmethionine (fMet)?
This bacterial regulatory protein can act as both a repressor and an activator, altering its conformation in response to mercury levels in the environment.
What is MerR protein?
This multi-subunit protein complex binds to the TATA box in the promoter region of genes, marking a key step in the formation of the pre-initiation complex during eukaryotic transcription initiation.
What is TFIID?
This factor in E. coli RNA polymerase is responsible for recognizing the promoter.
What is the sigma factor?
This enzyme is involved in transferring a guanine nucleotide to the 5' end of the pre-mRNA in a 5' to 5' triphosphate linkage.
What is guanylyl transferase?
This consensus sequence helps in identifying the start codon in eukaryotic mRNA.
What is the Kozak consensus sequence?
These RNA elements, often found in mRNAs, can change their shape in response to cellular conditions, thereby controlling gene expression by making the start codon more or less accessible.
What are riboswitches?
This type of mutation in the anticodon in tRNA can suppress stop codons, often involving tRNAs that misinterpret stop codons.
What is a suppressor mutation?
RNA Pol I, II, and III synthesize these types of RNA in eukaryotic transcription.
What are rRNA (RNA Pol I), mRNA (RNA Pol II), and tRNA/small RNAs (RNA Pol III)?
This enzyme family is known for its role in RNA editing, specifically for converting adenosine to inosine in double-stranded RNA, which can alter the coding sequence of mRNAs.
What is ADAR (Adenosine Deaminases Actiing on RNA?
In protein synthesis, this bacterial elongation factor binds to aminoacyl-tRNA, guiding it to the ribosome and ensuring the accuracy of tRNA selection in the A site.
What is EF-Tu?
This process describes the use of small, non-coding RNAs in eukaryotes to regulate gene expression post-transcriptionally, often by targeting mRNAs for degradation or translation inhibition.
What is RNA interference (RNAi)? or What is the role of miRNAs?
This general transcription factor is involved in both unwinding the DNA helix during transcription initiation and acts as a kinase to phosphorylate the CTD in the transition to transcription elongation.
What is TFIIH?
These are the main components of the pre-initiation complex in eukaryotic transcription.
What are general transcription factors, RNA polymerase II, and a mediator complex?
In RNA splicing, this small nuclear RNA component of the spliceosome base pairs with the branch point sequence, playing a critical role in the formation of the lariat structure during intron removal."
What is U2 snRNA?
In protein synthesis, this bacterial elongation factor is responsible for translocating the mRNA and tRNA within the ribosome, effectively moving the ribosome along the mRNA.
What is EF-G?
In the context of cholesterol metabolism, this family of membrane-bound transcription factors, when activated by specific cellular conditions, moves to the nucleus and upregulates genes involved in lipid synthesis and uptake.
What is SREBP (Sterol Regulatory Element Binding Protein)?
In bacterial cells, this RNA molecule acts as both tRNA and mRNA, rescuing ribosomes stuck on damaged mRNA and tagging the incomplete polypeptides for degradation.
What is tmRNA?