Question

in which ways can methylation affect transcription? multiple select question. rna polymerase movement is hindered by cpg methylation. methyl-cpg binding proteins recruit other proteins that inhibit transcription. the methylation of cpg islands may prevent or enhance the binding of regulatory transcription factors to the promoter region. methyl-cpg binding proteins recruit other proteins that enhance transcription.

Answer 1

Methylation affects transcription by hindering RNA polymerase movement through chromatin condensation and recruiting methyl-CpG binding proteins that attract other proteins that inhibit transcription. Methylation can also, although less commonly, recruit proteins that enhance transcription.

Step-by-step explanation:

Effects of Methylation on Transcription

Methylation can influence transcription in several ways. First, methylation of CpG islands in the promoter region of a gene can lead to recruitment of methyl-CpG binding proteins. These proteins can attract other proteins that compact the chromatin structure, leading to a transcriptionally inactive state, thereby inhibiting transcription. This process can prevent necessary transcription factors from accessing DNA and reduce the likelihood of transcription initiation by RNA polymerase. In some cases, however, methyl-CpG binding proteins may recruit factors that have a positive effect on transcription, although this is less common.

Specifically, two mechanisms by which methylation can affect transcription are:

• RNA polymerase movement can be hindered by the methylation of CpG sites, as this can lead to a condensed chromatin state that is inaccessible to the transcription machinery.
• Methyl-CpG binding proteins may recruit other proteins that inhibit transcription by further condensing the chromatin or by directly inhibiting transcription initiation.

The effects of methylation on gene expression are complex and can be influenced by various factors, including the environment and developmental stage of the organism.