What is one characteristic of non-coding DNA in relation to polypeptide genes?

Non-coding DNA plays a significant role in gene regulation despite not being translated into proteins. One of its key characteristics is that it can influence the expression of polypeptide genes. For instance, regions of non-coding DNA, such as enhancers and silencers, can bind transcription factors and other proteins that regulate the transcription of adjacent coding genes. This means that even though non-coding DNA does not contribute to the amino acid sequence of proteins, it can still have a profound effect on how much or when those genes are expressed, thereby playing a crucial role in cellular function and development.

In contrast, non-coding DNA does not serve as a template for protein synthesis, nor does it directly code for amino acids. While it can assist in the regulation of coding regions by enhancing expression, the more direct characteristic is its ability to influence gene regulation without being translated.