Can someone explains to me what transcription factors are?

[fredreload]

So I was reading how specialized cell is reverted to stem cell with transcription factors, which are proteins. What I want to know is essentially how it "controlling the rate of transcription of genetic information from DNA to messenger RNA" as Wikipedia says. If someone can provide me some insight of this it would be cool, especially what it means by "rate of transcription". How does it differ from what microRNA does?

Edited September 13, 2016 by fredreload

[BabcockHall]

Most transcriptional factors increase the rate of transcription, which is opposite to microRNA from what I can gather. The ones that I can think of bind to DNA at a promoter or an enhancer, but I would not be surprised to learn that some bind to other proteins that bind to DNA. General (basal) transcription factors are much more numerous in the eukaryotic world than in the bacterial world. The rate of transcription is not easy for me to define, but I would say that it is related to the number of mRNA transcripts from a given gene in a specified period of time.

[fredreload]

Most transcriptional factors increase the rate of transcription, which is opposite to microRNA from what I can gather. The ones that I can think of bind to DNA at a promoter or an enhancer, but I would not be surprised to learn that some bind to other proteins that bind to DNA. General (basal) transcription factors are much more numerous in the eukaryotic world than in the bacterial world. The rate of transcription is not easy for me to define, but I would say that it is related to the number of mRNA transcripts from a given gene in a specified period of time.

Hmm, I'm making a comparison between microRNA and the transcription factors mentioned here by Shinya Yamanaka. He was able to revert any cell to stem cell by adding simply four transcription factors. Now microRNA is able to change gene expression for lizards by turning genetic switches on and off as shown here, which is essential for lizard's tail regeneration, I assume it applies for all lizard regeneration. Now lastly for amphibians, the regeneration forms a blastema at the wound site which consists of progenitor cells, or I think stem cells. So in short lizard can make stem cells with microRNA, human also have microRNA, and I speculate that it could also turn any cell into stem cell by changing the gene expression. So we study what these four transcription factors do, and we create an artificial microRNA that would revert cells to stem cells at wound site for our own regeneration

 

P.S. What transcription factors do is essentially modifying gene expression too =/? I am not really sure. "Transcription factors perform this function alone or with other proteins in a complex, by promoting (as an activator), or blocking (as a repressor) the recruitment of RNA polymerase (the enzyme that performs the transcription of genetic information from DNA to RNA) to specific genes."

 

P.S. Alright, after studying, transcription factors act as an activator or repressor for the the rate that a particular sequence appears on mRNA. MicroRNA can also be used for gene expression to see if it gets transcribed to RNA. Note that one is mRNA and the other is RNA so they are still different, I will look into the differences over Lunar Festival

 

P.S. Here's a comparison between transcription factors and miRNA, this guy writes good

Edited September 13, 2016 by fredreload

[fredreload]

This video says it all

 

[CharonY]

 

 

P.S. Alright, after studying, transcription factors act as an activator or repressor for the the rate that a particular sequence appears on mRNA. MicroRNA can also be used for gene expression to see if it gets transcribed to RNA. Note that one is mRNA and the other is RNA so they are still different, I will look into the differences over Lunar Festival

 

P.S. Here's a comparison between transcription factors and miRNA, this guy writes good

 

Uhm, no that is at best a bit confused. TFs are generally proteins that bind to DNA and thereby control, one way or another the rate of transcription ("rate of a particular sequence appearing on mRNA" makes not sense whatsoever). Micro RNAs are involved in the post-transcriptional regulation. Look up what was known as the "central dogma of molecular biology" to get a better idea of the sequence of events from gene to protein.