BIOLOGY 101 Lecture Notes - Lecture 10: Intron, Peptide, Nuclear Export Signal
Document Summary
Transcription, gene: a segment of dna that contains instructions for making rna and sometimes a protein, transcription: produces the rna copy of a gene a. i. Produced whenever the cell needs it: some genes are protein coding, others only encode rna, we humans have 20,000 genes in our genome. Transcription: transcription: the synthesis of rna using a dna template a. i. All types of rna are made by transcription a. ii. Only one strand is the template strand in transcription: promoter: located upstream from transcription unit, where proteins bind to, requires rna polymerase, three steps: initiation, elongation, termination. Initiation: rna polymerase binds to promoter, rna polymerase unwinds dna and forms transcription bubble, rna adds nucleotides complementary to template strand c. i. In eukaryotes, transcription factors are required to bind to promoter before rna polymerase c. ii. 1. Tata box found in all eukaryote promoters c. ii. 1. b. Elongation: rna polymerase moves downstream, and produces more rna. Termination: for prokaryotes completes rna transcription, eukaryotes modify mrna after transcription b. i.
