Question

1. What is the importance of the TATA box and transcription factors

2.What is the importance of initiation complex

3.why should tRNA be charged with N-formylmethionine or methionine, what would happen if the tRNA was not charged?

Answer 1

1. Tata box is a DNA sequence which is present before the DNA sequence where the transcription begins and reads the direction of the transcription.

Transcription factors are boosters that turn on or off the genes that are to be transcripted. So transcription factors bind to Tata box and recruit RNA polymerase which synthesize RNA from DNA.

2. Initiation complex consists of components responsible for the initiation of translation. They are 30s ribosome subunit, mRNA, N-formyl methionine tRNA and three initiation factors. This complex initiates transcription and mRNA is synthesized by matching complementary bases to the DNA strand.

3. tRNA with N-formyl methionine is more stable and initiate the transcription process because  N-formyl methionine is coded with AUG codon. So act as the start codon for protein synthesis.tRNA with fmet tRNA is always attached to p site of ribosomal subunit. After initiation the tRNA enters into the A site of the subunit. So uncharged tRNA lacks this action and is slow.