Question

Briefly explain how a transcription factor located 10,000 nucleotides upstream of the promoter sequence can influence gene expression.

Answer 1

ANSWER :-

Transcription factor as we know aretproteins that bind DNA and regulate the process of transcription( DNA --> mRNA), by binding to a specific DNA sequence. In simple term, the transcription factor regulate the gene expression by promoting and suppressing the transciption. The transcription factors binds to either enhancer or promoter regions of DNA that are present adjacent to the genes that they regulate. Depending on the transcription factor , the transcription of the adjacent gene is either up-regulated or down -regulated. upstream is towards the 5' end of the RNA molecule.

when the transcription factor located 10,000 nucleotides upstream of the promoter sequence it influences the gene expression by binding with the promoter, it increases the gene transcription.The transcription factor or RNA polymerase binds to the binds to promoter or activator, the activator helps general transcription factor or RNA polymerase to assemble to begin the transcription. all these mechanism takes place on the target gene. The binding sites for the transcription factors are often close to a genes promoter. However, they are also found on the other parts of DNA , sometimnes very far away from the promoter like 10,000 nucleotide away upstrem, and still affect the transcription of gene. in such cases, the flexibility of DNA that allow transcription factor at distant binding sites to do their job. The DNA looped to bring far-off binding sited and transcription factors close to general transcription factors or proteins.