Gene Expression: Translation & Protein Synthesis Flashcards
What is gene expression?
process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA
Genes can be ____ ___ or ___ by various mechanisms
Turned on and off using gene regulation
Where does gene regulation occur?
Any point during gene expression but most commonly at the level of transcription
When does transcription or protein synthesis start?
Signals from the environment or from other cells activate transcription factor
What are two regulatory elements in the transcription process?
Enhancers and suppressors
What are the building blocks of proteins?
Amino acids (monomers)
What are the 9 essential amino acids?
Histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine
Amino acids joined together form _____?
Peptides, or longer chains called polypeptides
An amino acid has what groups?
- Carboxyl group
- Amine group
- Hydrogen
- Variable R group
A codon is ?
Sequence of three nucleotides that will be translated into a protein (from ribosome).
What is degenerate in the genetic code?
Different sequences of code that will produce the same protein.
What is required for codon reading?
_tRNA
What is the initiation codon?
AUG (met)
What are the three stop codons?
-UAA
-UGA
-UAG
Translation is a ____ energy consuming process
High energy
Consumes 90% of cell energy, 4 ATP / AA
What are the two sites called on the ribosome associated with mRNA?
P site (intiation) and A site (elongation)
In initiation what amino acid is always read?
Methionine at P site
What does mRNA do?
Carries instructions from DNA to ribosome for protein synthesis
_rRNA sequence. Are used. For working out ______ ______ among organisms
Evolutionary relationships
The Prokaryotic 70s ribosome has what subunit?
50S, 5S : 120 nt, 120 nt, 23S:2906 nt
The prokaryotic small ribosome has what small subunit?
30S (16S : 1542 nt)
The eukaryotic large subunit ribosome have what subunit?
25S, 5.8S, 5S
What eukaryotic ribosome has what small subunit?
40S (18S : 1869 nt)
The end products of protein synthesis is?
Primary structure of a protein
A sequence of amino acid bonded together by?
Peptide bonds
What happens to proteins destined to be part of a membrane or to be secreted?
There are glycosylation - addition of sugars to protein. The “O” linked serine/threonine happens in the golgi. The “N” linked asparagine happens in the ER
What is the “O” linked and where is it added?
O linked. Is serine / threonine; its added in the golgi
What is “N” linked. And where is it added?
“N” linked is asparagine; Added in the ER
List attachment or binding of groups.
NAD
Zn
Mg
FAD
What is proteolysis cleavage Truncation?
Will come back
What is disulfide bond bridges for?
Will come back
What is folding?
How does assembly of multiple subunits happen?
Will come. Back
What are R - group modifications?
Modifications of the R group. There are different ways for modification such as. Phosphorylation, methylation, acetylation, isoprenation, and hydroxy Latino.
What are pre-pro-proteins?
A protein precursor that contains a signal peptide sequence. It is a non polar sequence at the head of the growing polypeptide chain and contains many hydrophobic amino acid residues
How long are pre-pro-sequences?
About 30 non-polar amino acids long. It is important to guide the protein out of cell via secretions.
Pro-sequences are…?
Areas in protein essential for correct folding of protein. It can be involved in transporting and secretion of the pre-pro-protein.
Why would diabetes patients have their C-peptide levels measured?
It’s a means of distinguishing type 1 diabetes from. Type 2 diabetes or maturity onset diabetes of the young (MODY)
What does C-peptide levels tell the MLS about the patient?
-Determines how much of their own natural insulin a person is producing as C-peptide
A low C-peptide level means what for the patient?
Confirms Type 1 diabetes and insulin dependence.
What is associated with type 1 diabetes?
High glucose variability, hyperglycemia, and increased complications
What are point mutations?
Occurs in a genome when a single base pair is added, deleted or changed. While most point mutations are benign, they can also have various functional consequences, including changes in gene expression or alterations in encoded proteins.
What happens to the amino acids in frameshift?
Insertion or deletion of a nucleotide
A nonsense mutation may lead to what disease?
Alpha thalassemia
A frameshift mutation may lead to what disease?
Thalassemia, Abnormal hemoglobin Wayne where everything after 128 Bp is incorrect to 147 before stop.
Streptomycin or Gentamycin will target…?
30 S prokaryote initiation
Erythromycin will target what in gram + and gram - bacteria?
50 S prokaryotes
Chloramphenicol will target what part of the ribosomal subunit?
70 S ribosomal subunit in prokaryotes
Cyclohexamide will target?
80 S eukaryote translocation step, and fungus
Tetracycline will target…?
_tRNA to site A at 30 S subunit in prokaryotes
Puromycin will target…?
Premature terminator both pork and eukaryotes by mimicking tRNA binds at site A. It is resistant to hydrolysis
The Diphtheria toxin will inhibit what?
Eukaryote elongation factor II inhibitor
What two antibiotics will bind to the 30 S. Subunit of ribosome?
Aminoglycosides and tetracyclines
List antibiotics that bind to the 50S ribosomal subunit.
Chloramphenicol, erythromycin, and streptogramins
