从小就学基因的转录翻译，没想到现在做转录组，基因组项目是如此重要，仍旧需要经常拿出来复习体会，学了很多版本，但是说实话最喜欢 wikipedia 的这三张图。
一图胜千言！
1.The chemical structure of a four base pair fragment of a DNA double helix. The sugar-phosphate backbone chains run in opposite directions with the bases pointing inwards, base-pairing A to T and C to G with hydrogen bonds.
2.The structure of a eukaryotic protein-coding gene. Regulatory sequence controls when and where expression occurs for the protein coding region (red). Promoter and enhancer regions (yellow) regulate the transcription of the gene into a pre-mRNA which is modified to add a 5' cap and poly-A tail (grey) and remove introns. The mRNA 5' and 3' untranslated regions (blue) regulate translation into the final protein product.
3.The structure of a prokaryotic operon of protein-coding genes. Regulatory sequence controls when expression occurs for the multiple protein coding regions (red). Promoter, operator and enhancer regions (yellow) regulate the transcription of the gene into an mRNA. The mRNA untranslated regions (blue) regulate translation into the final protein products.
