RNA, Transcription and Translation 3.4 U3 Flashcards
What is a gene?
sequence of DNA that codes for a particular protein
DNA vs RNA
Sugar usedT vs UDouble vs single stranded
Types of RNA
tRNAmRNArRNA
tRNA
T-shaped structure made of RNA nucleotides. Amino acids are attached on the top, and the anticodon is on the bottom loop.Transfer RNA (tRNA) is responsible for carrying amino acids to the ribosome during translation and transferring them on to the growing polypeptide (amino acid) chain.
mRNA
Single stranded sequence of RNA nucleotides.Messenger RNA (mRNA) is an RNA copy of a gene that carries the instructions for producing a specific protein from the nucleus to the ribosome.
rRNA
Sequence of RNA nucleotides that bind to ribosomal proteins in order to form the whole ribosome. Ribosomal RNA (rRNA) is a structural component of ribosomes that assists with translation of messenger RNA .
Transcription in Prokaryotes vs. Eukaryotes
PROKARYOTESOccurs in the cytoplasmNo processing requiredEUKARYOTESOccurs in the nucleusProcessing required before leaving nucleus
What is a promoter?
Certain DNA sequences right before genes, where proteins bind to initiate transcriptionTFs = regulateTranscription factors
What is RNA polyamerase?
puts RNA nucleotides together in a growing chain using DNA strand as a templatealso unzips DNA like Helicase!makes RNA strand in 5’ to 3’ direction!
What is a 5’ Cap?
Specially modified guanine nucleotide that is added to the 5’ end of the transcript. It protects the mRNA from degradation in the cytoplasm and also helps the ribosome to bind at the the mRNA start codon to initiate translation.
What is a exons?
Sequences of mRNA that actually code for part of the protein.
What is a introns?
Sequences of mRNA that exist between exons and allow for alternative splicing.
What is a Poly A Tail?
A series of A nucleotides added to the 3’ end of the transcript. It aids in nuclear export ,protects the mRNA from degradation in the cytoplasm, and also helps the ribosome to bind at the the mRNA start codon to initiate translation.
What is alternative splicing?
Alternative splicing, or alternative RNA splicing, or differential splicing, is an alternative splicing process during gene expression that allows a single gene to code for multiple proteins. In this process, particular exons of a gene may be included within or excluded from the final, processed messenger RNA (mRNA) produced from that gene.[1] This means the exons are joined in different combinations, leading to different (alternative) mRNA strands. Consequently, the proteins translated from alternatively spliced mRNAs will contain differences in their amino acid sequence and, often, in their biological functions
Where does Eukaryotic Translation occur?
Eukaryotic translation occurs on ribosomes attached to the rough endoplasmic reticulum or those found free-floating in the cytoplasm.
