LIFE 102 Lecture Notes - Lecture 21: Morphogen, Small Interfering Rna, Microrna

• School: CSU
• Department: Life Science
• Course: LIFE 102
• Professor: Bedinger, Patricia A

Document Summary

Gene expression: epigenetics/chromatin structure, dna methylation, histone modification, transcription, transcription factors, enhancers, alternative splicing, rna stability/translation, micrornas. Transcription: a typical eukaryotic gene has enhancers in addition to promoters (both are dna sequences). May be far away from the promoter (distal) Transcription factors are proteins that bind to dna and control whether transcription starts or now. For transcription initiation in eukaryotes, a combination of transcription factors (proteins) will bind to promoters and enhancers, allowing rna polymerase to load onto a gene and begin transcription. Enhancers are often tissue-specific, so whether or not a gene gets transcribed often will depend on whether the enhancer-binding transcription factors are present in a cell. Alternative splicing: alternative splicing is turning out to be more important than we thought, As a result, you can get different mrnas from the same primary transcript. Micro rnas (mirna, sirna, rnai) are small non-coding (nc) that can interfere with gene expression by inhibiting translation or causing degradation of target mrnas.