TATA Box -

Upstream from the cap site one normally encounters one or two short sequence elements that are common to many eukaryotic genes and that seem to be involved in normal transcription. Of the sequences thought to be important in transcription initiation, the TATA box or Goldberg Hogness Box is the best characterized.

This sequence, or one very similar to it, occurs at about nucleotide -30 (30 nucleotides upstream from the cap site) in almost all plant and animal genes. This sequence is required for correct expression of eukaryotic genes in vitro and accurate, efficient initiation in vivo.

Since plant genes are also transcribed by RNA polymerase it is not surprising that all the plant genes have a sequence analogous to the TATA box. The distance between the TAT A box (measured from the second T) and the cap site is 29-33 nucleotides, as in other eukaryotes.