The key difference between TATA and CAAT box is that TATA box is a conserved nucleotide region which has a consensus sequence of TATAWAW while CAAT box is a conserved nucleotide region with a consensus sequence of GGCCAATCT.
TATA box and CAAT box are two regions of nucleotides that influence transcription of eukaryotic genes. They are non-coding DNA sequences found upstream to the transcription initiation site. In fact, they are found in the regulatory region, which is known as the promoter. Both TATA box and CAAT box are responsible for the efficiency of transcription. They are consensus sequences which have not changed throughout the evolutionary process.
CONTENTS
1. Overview and Key Difference
2. What is TATA Box
3. What is CAAT Box
4. Similarities Between TATA and CAAT Box
5. Side by Side Comparison – TATA vs CAAT Box in Tabular Form
6. Summary
What is TATA Box?
TATA box or Goldberg-Hogness box is a consensus sequence found in the promoter region of eukaryotic genes. TATA box is a core element of the promoter. It is located 25 base pairs upstream of the transcription initiation site. It is conserved throughout the evolutionary process. The consensus sequence of TATA box is TATAWAW, where W is either A or T. It is a non-coding DNA sequence. However, TATA box is important for the transcription of the gene. It is the binding site of TATA-binding protein (TBP) and other transcription factors. Once they bind into the TATA box, the recruitment of RNA polymerase II and proper regulation of transcription takes place in eukaryotic genes.
Figure 01: TATA Box
Since TATA box is involved in the regulation of transcription, mutations of TATA box can result in phenotypic changes leading to diseases such as gastric cancer, spinocerebellar ataxia, Huntington’s disease, blindness, β-thalassemia, immunosuppression, Gilbert’s syndrome, and HIV-1, etc.
What is CAAT Box?
CAAT box is a region of nucleotides with the consensus sequence of GGCCAATCT. Similar to TATA box, CAAT box is also located in the promoter region of the gene. Therefore, it is located about 75-80 base pairs upstream to the transcription site.
Figure 02: CAAT Box
Specific transcription factors bind to the CAAT box. This binding stabilizes the preinitiation complex for easier binding of the enzyme RNA polymerase. Likewise, the CAAT box works as a regulatory sequence. Mutations in the CAAT box region highly affect the promoter response and regulation of transcription.
What are the Similarities Between TATA and CAAT Box?
- TATA and CAAT are two regions of nucleotides found in the regulatory sequence of eukaryotic genes.
- They are found upstream to the transcription initiation site.
- Both are consensus DNA sequences.
- They are essential for the regulation of transcription, so they are regulatory sequences.
What is the Difference Between TATA and CAAT Box?
TATA box is a conserved nucleotide region found about 25-30 base pairs upstream to the transcription initiation site. On the other hand, CAAT box is a conserved region of nucleotides found about 75-80 base pairs upstream to the transcription initiation site. So, this is the key difference between TATA and CAAT box. Besides, TATA box has a consensus sequence of TATAWAW while GGCCAATCT is the consensus sequence of CAAT box.
Moreover, another significant difference between TATA and CAAT box is that the TATA box provides a binding site for TBP and transcription factors and participates in transcription regulation while the CAAT box signals the binding site for the RNA transcription factor.
Below infographic summarizes the differences between TATA and CAAT box.
Summary – TATA vs CAAT Box
TATA box and CAAT box are two parts of the conserved region of eukaryotic gene promoters. They are located upstream to the transcription initiation site. Both influence the transcription of genes by providing sites for binding TATA-binding proteins and transcription initiation factors. TATA box is located 25-35 base pairs upstream of the transcription initiation site while CAAT box is located 75-80 base pairs upstream to the transcription initiation site. The consensus sequence of TATA box is TATAWAW while the consensus sequence of CAAT box is GGCCAATCT. Thus, this is the summary of the difference between TATA and CAAT box.
Reference:
1. “TATA Box”. En.Wikipedia.Org, 2020, Available here.
2. Byeongwoon Song, C. S. H. Young. “Functional Analysis Of The CAAT Box In The Major Late Promoter Of The Subgroup C Human Adenoviruses”. Pubmed Central (PMC), 2020, Available here.
Image Courtesy:
1. “TATA box mechanism” By Luttysar – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “CCAAT DNA4” By Sfkuo – Own work (CC BY-SA 4.0) via Commons Wikimedia