mature RNA
copy of DNA that includes exons. (introns already cut out). this is what gets translated into amino acids
transcription
copies info from a DNA sequence (a gene) to a complementary RNA sequence. requires one strand of DNA to act as a template, nucleotides, an RNA polymerase (enzyme). occurs in nucleus. 3 phases: initiation, elongation and termination
initiation (transcription)
phase of transcription. requires a promoter. the start of transcription
transcribed into RNA and then cut out. intervening regions
noncoding regions / introns
wobble position
the last (3rd) position of the codon is not as important or picky. it can have different bases and result in same amino acid
P (polypeptide) site
tRNA binding site in ribosome large subunit. where tRNA adds its amino acid to the growing chain
proteins are always made from amino terminus (N) to carboxyl terminus (C). amino acids are connected with covalent bonds called peptide bonds
N to C
has three tRNA binding sites: A (amino acid) site, P (polypeptide) site and E (exit) site
large ribosomal subunit
PKU
disease where people can't break down phenylalanine, it builds up and hinders brain development. this happens if they eat a normal protein diet. this can be treated with a gene-environment interaction (special diet with protein that is already broken down past phenylalanine)
translation ends with stop codon enters A site. C terminus is the last amino acid added. stop codon binds a protein release factor. then ribosome falls apart, mRNA comes off ribosome, "everything falls apart"
termination (translation)
a post translational modification. cutting proteins. cut a long polypeptide chain into final products
proteolysis
disease where people can't break down phenylalanine, it builds up and hinders brain development. this happens if they eat a normal protein diet. this can be treated with a gene-environment interaction (special diet with protein that is already broken down past phenylalanine)
PKU
noncoding regions / introns
transcribed into RNA and then cut out. intervening regions
nonsense mutation
change in DNA that results in a premature stop codon and therefore a shortened (truncated) protein. usually makes protein not functional (unless it is near the end at the 3' end). "stop the nonsense"
frame-shift mutation
change in DNA caused by insertion or deletion of bases (any number that is not a multiple of 3). this shifts the "reading frame" and change the amino acids encoded because 3 codons encode 1 amino acid. this produces non functional proteins
glycosylation
a post translational modification. carbs/sugars added to protein
study of nucleic acids and proteins and often focuses on gene expression
molecular biology
links info in mRNA codons with specific amino acids. this binds to an amino acids and becomes "charged". binds its anticodon to codon of mRNA (which is complementary). also interacts with ribosomes. must read codon correctly and deliver amino acids corresponding to each codon.
tRNA
mRNA
an RNA copy of the DNA, temporary molecule, carries this copy from nucleus to ribosome. 5' cap and poly A tail are also added to this
initiation (translation)
after initiation complex is bound to mRNA, small subunit reads along mRNA looking for the start codon. then large subunit binds to the complex (with the APE site). tRNA enters ribosome at the P site (all other tRNA enters at A site).
pre-mRNA is not spliced correctly and an intron sequence is not removed. when it is translated it doesn't encode for protein so it produces "garbage", a non functional beta-globin protein that usually carries oxygen. this results in anemia and you need regular blood transfusions
mutation at intron consensus sequence (border between exon and intron)
messenger RNA (mRNA), ribosomal RNA (rRNA), transfer RNA (tRNA)
3 kinds of RNA in protein synthesis
E (exit) site
tRNA binding site in ribosome large subunit. where tRNA sits before being released from the ribosome. (it will then get "recharged" by another amino acid)
fidelity function
in ribosomal small subunit, makes sure hydrogen bonds between codon and anticodon match up. checks for mimatches
silent mutation
change in the DNA that doesn't affect the amino acids or proteins. e.g. occuring in introns or between genes, or if it changes a base that doesn't affect amino acid sequence (Wobble position)
dictates how protein will fold
primary structure
change in DNA that results in a premature stop codon and therefore a shortened (truncated) protein. usually makes protein not functional (unless it is near the end at the 3' end). "stop the nonsense"
nonsense mutation
nuclear localization signal (NLS)
stretch of amino acids that tell proteins to go to the nucleus
primary structure
dictates how protein will fold
signal sequence / signal peptide
tells proteins where to go in the cell
