Search results
Results from the WOW.Com Content Network
A typical operon. In genetics, an operon is a functioning unit of DNA containing a cluster of genes under the control of a single promoter. [1] The genes are transcribed together into an mRNA strand and either translated together in the cytoplasm, or undergo splicing to create monocistronic mRNAs that are translated separately, i.e. several strands of mRNA that each encode a single gene product.
Attenuators may be classified according to the type of molecule which induces the change in RNA structure. It is likely that transcription-attenuation mechanisms developed early, perhaps prior to the archaea/bacteria separation and have since evolved to use a number of different sensing molecules (the tryptophan biosynthetic operon has been found to use three different mechanisms in different ...
There are 52 genes that encode the ribosomal proteins, and they can be found in 20 operons within prokaryotic DNA. Regulation of ribosome synthesis hinges on the regulation of the rRNA itself. First, a reduction in aminoacyl-tRNA will cause the prokaryotic cell to respond by lowering transcription and translation. This occurs through a series ...
[21] [22] Transcription elongation is a processive process. Double stranded DNA that enters from the front of the enzyme is unzipped to avail the template strand for RNA synthesis. For every DNA base pair separated by the advancing polymerase, one hybrid RNA:DNA base pair is immediately formed. DNA strands and nascent RNA chain exit from ...
Regulation of gene expression by a hormone receptor Diagram showing at which stages in the DNA-mRNA-protein pathway expression can be controlled. Regulation of gene expression, or gene regulation, [1] includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products (protein or RNA).
transcriptional regulation – controlling the rate of gene transcription for example by helping or hindering RNA polymerase binding to DNA; transcription – the process of making RNA from a DNA template by RNA polymerase; transcription factor – a substance, such as a protein, that contributes to the cause of a specific biochemical reaction ...
Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. In virology, the term transcription is used when referring to mRNA synthesis from a viral RNA ...
Abortive initiation is a normal process of transcription and occurs both in vitro and in vivo. [2] After each nucleotide-addition step in initial transcription, RNA polymerase, stochastically, can proceed on the pathway toward promoter escape (productive initiation) or can release the RNA product and revert to the RNA polymerase-promoter open complex (abortive initiation).