BIOL 202 Lecture Notes - Lecture 29: Small Interfering Rna, Mitosis, Methylation
Document Summary
Non dandelion genetics (epigenetic: determined by nucleus dna (transcription, determined by factors in cytoplasm. Random event, cells independent of each other. E. g. cat fur color the allele on the active chromosome determines the cat fur color makes orange and black patches. Tissue specific histone modification: different genes are active in different tissues depends on cell type, dan methylation by dnmt (doesn"t affect base paring) When methylated in cpg islands, the gene expression is silenced. By blocking factor binding, or by histone modifications. Methyl-cpg-binding domain (mbd) proteins, recruit other enzymes to promote histone modification: methylation pattern is reserved in dna heritable. Dnmt has high affinity for hemimethylated sites methylation of the new strand. *honey bees: queen and workers are genetic identical, queen develop by eating royal jelly, worker larvae fed by sirna develop queen ovaries. Genomic imprinting (human and mouse: even though we have two copies of an allele from parents, only one copy of allies is expressed.
