TRANSCRIPTION OF PROKARYOTESES VIROLOGY .pptx

VIROLOGY

1. TRANSCRIPTION OF PROKARYOTES Presented By: Muhammad Kashif Nazir

2. INTRODUCTION Definition: A central event in gene expression is the copying of the sequence of the template strand of a gene into a complementary RNA transcript. All cells have at least one kind of RNA polymerase the enzyme that transcribes RNA from DNA and the machinery that translates the mRNA into protein. In bacteria, transcription and translation are said to be “coupled,” since they occur within a single cellular compartment. Transcription takes place in the cytoplasm in prokaryotes. The whole process of transcription and translation occurs within minutes.

3. Bacterial Promoter Structure If nucleotide sequences of DNA are aligned with each other and each has exactly the same series of nucleotides in a given region, the sequence is said to be conserved. Transcription begins with the binding of the RNA pol holoenzyme to a region of the DNA known as the promoter, which is not transcribed. It serves as start signal for RNA polymerase to start reaction.