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Properties of eukaryotic transcription

  • Complex!
  • RNA polymerase is the main protein that creates the RNA transcript
  • Proteins called transcription factors help RNA polymerase and regulate it's function.
  • 2 types of transcription factors: basal tfs and modulatory tfs.
  • Basal transcription factors - required for all transcription events.
  • Modulatory transcription factors - regulate expression of genes. Both positive and negative regulation.
  • Transcription factors can act from relatively far away. Up to 10kb!
  • pre-mRNA transcripts are spliced to remove exons.
  • Alternative splicing allows the cell to combine exons differently in the final mRNA transcript from the same pre-mRNA transcript.

Transcription in five easy steps

  • Transcription of DNA to pre-mRNA. DNA, RNA polymerase and transcription factors.
  • Addition of 5' methyl guanosine cap to pre-mRNA transcript.
  • Splicing of pre-mRNA transcript (yields mRNA proper)
  • Addition of 3' poly(A) tail to mRNA transcript.
  • mRNA is transported to the cytoplasm.

5 steps of mrna preparation

Rna polymerase - main protein that creates rna transcript.

RNA polynmerase is the protein whose job it is to 'read' the genetic code and create a complimentary RNA transcript from that code. Eukaryotes have three different types of RNA polymerases: RNA polymerase I, II, and III. RNA polymerase II is the from of polymerase that transcribes most genes and is the form of polymerase with which we need to concern ourselves.

Initiation of transcription

Transcription initiation in eukaryotes is complicated, and the details are not entirely understood (although we do have a good grasp on the basic mechanism). The fully assembled eukaryotic transcription inititation complex contains more than 50 polypeptides. RNA polymerase II has more than 10 polypeptide subunits by itself. Keep in mind that the process outlined below is a generalization, and any given, specific transcription event will probably vary some in the details. For example, although the TATA box is the most strongly conserved promoter sequence, it is by no means present in every eukaryotic promoter. Also, there is some debate as the importance of the order of the binding of the proteins in the initiation complex: it was thought that a specific order was vital, now, however, new evidence suggests that reaching the end binding state may be what is really important, whatever the order.

Transcription factors - help/regulate rna polymerase's function

Transcription factors (tfs) are proteins involved with transcription - except for RNA polymerase. Transcription factors can be broken down into two groups: basal tfs and modulatory tfs. Eukaryotic RNA polymerases are not capable of initiating transcription alone, they require the assistance of a set of basal transcription factors. Basal tfs assist RNA polymerase in the recognition of promoter sequences and unwiding the DNA double helix, among other functions. Basal tfs are necessary for every transcription event. Modulatory transcription factors regulate the expression of a gene, or a set of gene. These tfs are important because they allow the body to differentially express genes at different times and different places in the body. Modulatory tfs are vital for multicellular life. They allow the body to create different cells, tissues, and organs.

Questions & Answers

Discuss the differences between taste and flavor, including how other sensory inputs contribute to our  perception of flavor.
John Reply
taste refers to your understanding of the flavor . while flavor one The other hand is refers to sort of just a blend things.
Faith
While taste primarily relies on our taste buds, flavor involves a complex interplay between taste and aroma
Kamara
which drugs can we use for ulcers
Ummi Reply
omeprazole
Kamara
what
Renee
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Renee
is a drug
Kamara
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Kamara
Omeprazole Cimetidine / Tagament For the complicated once ulcer - kit
Patrick
what is the function of lymphatic system
Nency Reply
Not really sure
Eli
to drain extracellular fluid all over the body.
asegid
The lymphatic system plays several crucial roles in the human body, functioning as a key component of the immune system and contributing to the maintenance of fluid balance. Its main functions include: 1. Immune Response: The lymphatic system produces and transports lymphocytes, which are a type of
asegid
to transport fluids fats proteins and lymphocytes to the blood stream as lymph
Adama
what is anatomy
Oyindarmola Reply
Anatomy is the identification and description of the structures of living things
Kamara
what's the difference between anatomy and physiology
Oyerinde Reply
Anatomy is the study of the structure of the body, while physiology is the study of the function of the body. Anatomy looks at the body's organs and systems, while physiology looks at how those organs and systems work together to keep the body functioning.
AI-Robot
what is enzymes all about?
Mohammed Reply
Enzymes are proteins that help speed up chemical reactions in our bodies. Enzymes are essential for digestion, liver function and much more. Too much or too little of a certain enzyme can cause health problems
Kamara
yes
Prince
how does the stomach protect itself from the damaging effects of HCl
Wulku Reply
little girl okay how does the stomach protect itself from the damaging effect of HCL
Wulku
it is because of the enzyme that the stomach produce that help the stomach from the damaging effect of HCL
Kamara
function of digestive system
Ali Reply
function of digestive
Ali
the diagram of the lungs
Adaeze Reply
what is the normal body temperature
Diya Reply
37 degrees selcius
Xolo
37°c
Stephanie
please why 37 degree selcius normal temperature
Mark
36.5
Simon
37°c
Iyogho
the normal temperature is 37°c or 98.6 °Fahrenheit is important for maintaining the homeostasis in the body the body regular this temperature through the process called thermoregulation which involves brain skin muscle and other organ working together to maintain stable internal temperature
Stephanie
37A c
Wulku
what is anaemia
Diya Reply
anaemia is the decrease in RBC count hemoglobin count and PVC count
Eniola
what is the pH of the vagina
Diya Reply
how does Lysin attack pathogens
Diya
acid
Mary
I information on anatomy position and digestive system and there enzyme
Elisha Reply
anatomy of the female external genitalia
Muhammad Reply
Organ Systems Of The Human Body (Continued) Organ Systems Of The Human Body (Continued)
Theophilus Reply
what's lochia albra
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Source:  OpenStax, Statistical machine learning for computational biology. OpenStax CNX. Oct 14, 2007 Download for free at http://cnx.org/content/col10455/1.2
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