No, expression from an SV40 promoter does not require a TATA box upstream of the transcription start site. The SV40 promoter is a complex promoter that contains multiple elements that are required for transcription initiation. These elements include the TATA box, the initiator (INR), and the enhancer. The TATA box is not essential for transcription initiation from the SV40 promoter, but it can increase the efficiency of transcription. The INR is a short sequence of DNA that is located immediately upstream of the transcription start site. The INR is essential for transcription initiation from the SV40 promoter. The enhancer is a region of DNA that is located upstream of the promoter. The enhancer can increase the efficiency of transcription from the SV40 promoter.

In your case, you can design a plasmid with an SV40 promoter-driven antibiotic resistance without a TATA box. The plasmid will still be able to express the antibiotic resistance gene, but the efficiency of transcription may be slightly lower.

The SV40 (Simian virus 40) promoter is a strong viral promoter commonly used for driving gene expression in various experimental systems. While the presence of a TATA box upstream of the transcription start site is a common feature in many promoters, the SV40 promoter is unique in that it lacks a canonical TATA box.

The SV40 promoter utilizes an alternative mechanism for transcription initiation called the "TATA-less" promoter. Instead of relying on a TATA box, it utilizes other elements and transcription factors to initiate transcription. The absence of a TATA box in the SV40 promoter does not necessarily impair its ability to drive gene expression.

Therefore, in your current cloning strategy where the transcription start site is located just 8bp from the end of the SV40 promoter, it is likely that the expression can still occur without the presence of a TATA box. The SV40 promoter contains other regulatory elements and transcription factor binding sites that can facilitate transcription initiation.

However, it's worth noting that the exact transcriptional activity may depend on the specific context and the downstream sequence elements present in your plasmid. Experimental verification, such as measuring the expression levels of your gene of interest, can help confirm the functionality of the modified SV40 promoter in your specific system.

SV40 is a strong promoter itself and like all promoter has it's intrinsic TATA box sequence

SV40 Promoter does not need TATA Box.

Explained in detail by John Odonnel and Saif Wahid.

Thank you.