What is the purpose of an octamer box?
What is the purpose of an octamer box?
The octamer binding site, which is located immediately upstream of the poorly conserved DRA TATA sequence, is important for high levels of expression of this human major histocompatibility class II gene in B cells.
What is the octamer box?
From Wikipedia, the free encyclopedia. Octamer transcription factors are a family of transcription factors which binds to the “ATTTGCAT” DNA sequence. Their DNA-binding domain is a POU domain. There are eight Octamer proteins in humans (Oct1–11), which have been renamed according to the different classes of POU domain.
What is Oct1 transcription factor?
One of the earliest described mammalian transcription factors, Oct1 was identified as a protein associated with regulatory DNA binding sites in animal viruses that were used to study gene regulation during the 1980s: adenovirus, SV-40 and herpes simplex virus-1 [1–3].
Where is the GC box located?
promoter region
In molecular biology, a GC box, also known as a GSG box, is a distinct pattern of nucleotides found in the promoter region of some eukaryotic genes. The GC box is upstream of the TATA box and approximately 110 bases upstream from the transcription initiation site.
How is histone octamer formed?
A histone octamer is the eight protein complex found at the center of a nucleosome core particle. The octamer assembles when a tetramer, containing two copies of both H3 and H4, complexes with two H2A/H2B dimers. Each histone has both an N-terminal tail and a C-terminal histone-fold.
What are the coding sequences called?
exons
The continous coding sequences are called exons and the intervening non-coding sequence are called introns.
What do nucleosomes do?
Nucleosomes are the basic packing unit of DNA built from histone proteins around which DNA is coiled. They serve as a scaffold for formation of higher order chromatin structure as well as for a layer of regulatory control of gene expression.
How does Oct1 recognize the position?
Once bound to DNA, the DNA bends to bring Oct1 and the gene together. How does Oct1 recognize the position on the DNA molecule where it should bind? Transcription factors recognize the binding site based on the specific sequence of the enhancer/binding site/promoter.
What is bacterial promoter?
Promoters in bacteria contain two short DNA sequences located at the -10 (10 bp 5′ or upstream) and -35 positions from the transcription start site (TSS). Their equivalent to the eukaryotic TATA box, the Pribnow box (TATAAT) is located at the -10 position and is essential for transcription initiation.
What is histone octamer role in human genome?
A histone octamer contains eight proteins of four different types i.e., two copies of each H2A, H2B, H3 and H4. The negatively charged DNA is wrapped around the positively charged histone octamer to form a structure called nucleosome.
Which is gene promoter contains the octamer sequence motif?
Immunoglobulin (Ig) gene promoters contain the octamer sequence motif ATGCAAAT which is recognized by cellular transcription factors (Oct factors). Besides the ubiquitous Oct-1 factor, there is also a group of related factors (Oct-2 factors) encoded by a separate gene.
Which is the best definition of an octamer?
Definition of octamer. : a polymer formed from eight molecules of a monomer.
What kind of promoter has a weak octamer site?
Unexpectedly, we find that octamer/TATA promoters with a high affinity octamer site direct ubiquitous expression. By contrast, promoter constructions that behave in a B cell-specific manner tend to have a weak octamer binding site.
What is the role of octamer in CSCs?
(4-7) Markers of CSCs include Sry-related HMG box (SOX2) and octamerbinding transcription factor 4 (OCT4), which are thought to regulate the apoptosis pathway (via caspase-3), telomerase function (via human telomerase reverse transcription or hTERT), and DNA damage repair (via checkpoint kinase 1 or Chk1).
