BI226 Lecture Notes - Lecture 7: Microsatellite, Ribosomal Rna, Transfer Rna
Document Summary
The antennapedia and bithorax complexes in drosophila are involved in a segmental pattern and determine the development of cells in each particular segment. Multiple copies in genome, like rrna, trna and some protein encoding genes. Includes microsatellites (short tandem repeats (strs) and minisatellites. Sines (short interspersed elements) and lines (long interspersed elements) Rna polymerase forms a large protein complex with transcription factors that bind. Enhancer sequences are more variable in their location to the promoter. Can be found upstream, downstream or even within the gene itself thousands of bp away. Made possible by bending of dna in the region. Eukaryotic dna is wrapped around histones and other chromatin proteins. Chromatin remodeling proteins can acetylate the histones causing the conformation to relax to relax. Methylation of dna is associated with transcriptional changes. Especially with cytosine followed by a guanine (cpg sites) Clusters of dna with 5-methylcytosine-p-guanine sites is associated with transcriptionally inactive dna silenced.
