Lecture 8/29/18 Flashcards
Where is DNA and RNA ?
Red = newly syntheszied DNA
green = newly synthesized RNA
Which one of these are not synthesized in the nucleus?
non protein encoding RNA
Ribosomes
proteins encoding RNA
telomerase
ribosomes
what causes mRNA to be processed in “factories”?
Scaffold proteins maintain transcription accessory proteins in close proximity to RNA poly
Aggregation factors accumulate the componets necessary for trancription into region
True for false. A microRNA is a protein coding RNA molecule
FALSE
its a NON PROTEIN coding RNA
What are the steps of translation (7)
- RNA poly (II) together with trancription factors bind to promotor DNA
- RNA polymerase creates a transcription bubble which separates the two strand of the DNA helix. This is done by breaking the hydrogen bonds b/w complementary DNA nucleotides
- RNA polymerase adds RNA nucleotides (which are same nucleotides of non template DNA strand)
- RNA-sugar -phosphate backbone forms with by RNA poly (II) to form RNA strands
- Hydrogen bonds of the RNA-DNA helix break, free the newly synthezised RNA strand
- In eukaryotes, post transcriptional process includes poly adentlation, 5’ capping , and splicing
- The RNA may remain in nucleus or exit through the nuclear pore complex
What on mRNA is used to ID where it will be sent?
The 3’ polyadenylene tail and the 5’ cap
What happens after mRNA is process?
It is sent out of the cell
Through a nuclear pore complex via nuclear export receptor proteins.
Which is these is not done in the Nucleous?
A. rRNA transcription
B. Assembly of of snoRNA to snRNA
C. Telomerase assembly
D. Additon of the 40s subunit to 60s subunit
E. B and C
F. B and D
I. All of the above are done in Nucleous
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What is the last fine quality control point of mRNA ?
nonsense mediated decay
eliminates mRNA witha premature stop codon
What are the most common biochemical modifications of noncoding RNAs?
(includes splicesomes)
pseudouridylation and 2’O ribose methylation
True or false: All eukaryotes have and use miRNA
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What is the Nucleolus ?
a non membrane bound structure that is houses rRNA processing and assembly into ribosomes
How many nucleotides does miRNA have?
22 nucleotides
What is miRNA main function?
RNA silencing
What is a Cajal boidies>
where snoRNA is made into snRNPs
Fibrillian is in both cajal bodies and nucleous
Coilin is only found in the cajal body
T or F
In humans, The genes encoding rRNA are found on 10 loci or different chromosomes
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Of all protein genes, how much regulated expression is controlled by miRNAs?
70%
When is the Nucleolus and nuclear membrane dissociated and reassembled ?
Assocation occurs in (telophase of mitosis) or G2, and Dissocation occurs at the at prophase in mitosis
true or false: 1 miRNA affects the translation of 1 gene
FALSE:
1 micro RNA can affect multiple genes because genes have consensus sequences that cause formation of a family of proteins whose mRNA can be affected
What is snRNA made of and what does it do?
It is made uo of snoRNA +specfic proteins
It implements biochemical modifications of non coding RNAs
True of False
The size of nucleolous reflects the cells need to gnereate protein
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How is miRNA created and processed?
What is the difference between exosomes in a molecular sense and a clincally sense?
- Molecular
- it contains RNA nucleases that are used to degradate damaged mRNA before it leaves the cell
- Clinically
- In circulatoru sys travels in the body sending msg (intra tissue) about pathological process.
- EVIDENCE
- Iintracellular communication with macromolcules b/w cells
- spreading of mRNA,miRNA,DNA,proteins,lipids, and other factors in deveopment of dieases
- vector for drugs
What benefit does miRNA have in vitro?
we can use it to knock out mRNA CREATED BY genes
