Chapter 8- RNA: Transcription and Processing
the part of the transcribed gene that leaves the nucleus
the part of the transcribed gene that is removed and stays in the nucleus
removes introns and joins exons together
allows for more than one protein to come from the same gene- more than one RNA can be made from the same gene
ncRNA stands for
non coding RNAs
RNAs that do not encode for proteins
Differences between DNA and RNA
1. RNA is single stranded (can take on a 3D structure)
2. Has a ribose sugar (has a hydroxyl on the 2' carbon of the sugar)
3. Nucleotide base Uracil not Thymine
4. Can catalyze biological reactions
RNA that can catalyze biological reactions
What sugar is this?
What sugar is this?
What are the purine nucleotides?
adenine and guanine
What are the pyrimidine nucleotides?
cytosine, thymine, and uracil
What are the two classes of RNA?
messenger RNA and functional RNA
Name the types of functional RNA
-transfer RNA (tRNA)
-ribosomal RNA (rRNA)
-small nuclear RNAs (snRNAs)
-small interfering RNAs (siRNAs)
-long noncoding RNAs (lnc RNAs or ncRNAs)
brings the proper amino acid to the mRNA during translation
the major component of ribosomes
small nuclear RNAs
processes RNA transcripts in eukaryotic cells (ex. splicesosome)
small interfering RNAs and piwi RNAs
protect the integrity of plant and animal genomes, prevents the spread of transposons in plants and animals
Long noncoding RNAs
genomic sequence, may play a role in dissage compensation, but otherwise the function is unknown
RNAs which are continuously synthesized
the first step in obtaining protein from a gene
enzyme used in transcription
the sequence found on the non-template strand
What are the three stages of transcription?
initiation, elongation, and termination
DNA sequence that promotes the operon for RNA polymerase to bind and synthesize
DNA before the first transcribed base (AUG)
DNA after the first transcribed base (AUG)
untranslated region between the promoter and the beginning of coding the gene
What triggers elongation?
recognition of the sigma factor and its release will trigger elongation
DNA unwinds in front of the polymerase and rewinds after it
Where does the energy for the new bonds in elongation come from?
the splitting of the high-energy triphosphate and release of inorganic diphosphate
How is RNA synthesis terminated?
last 40 bp are GC rich in order to form a hairpin loop that ends with several U bases. The rho protein helps because it causes RNA polymerase to fall off