Ribosome: The ribosome’s job is to hold everything in place, as well as form the bonds between amino acids. All cells have ribosomes. Ribosomes are made of RNA and associated proteins, with a small subunit and a large subunit coming together during translation to catalyze protein synthesis.
As mentioned above, the generation and disappearance of Fmoc based chromophors allows the monitoring of the synthesis. Furthermore, samples may be taken to determine the load of Fmoc peptide. The completion of the deprotection reaction may be checked by cleaving samples and analyzing the obtained peptide.
Protein biosynthesis - Wikipedia
In prokaryotes RNA processing is not necessary, but in eukaryotes the RNA must be processed before translation can occur.
3 main steps:
capping at 5' end
RNA splicing to remove introns
addition of polyA tail
Primary transcript is the initial product of transcription of an mRNA
Most genes have their protein-coding information interrupted by non coding sequences called
The 5' end of the primary transcript (pre-mRNA) is synthesized first.
The 5' cap is a modified guanine nucleotide which attaches to the 5-end of the pre-mRNA.
The cap protects the RNA from being degraded by enzymes that degrade RNA at the 5' end.
RNA splicing removes introns and exons are joined.
exons are a sequence within a primary transcript that remains in the RNA after RNA processing.
RNA splicing begins with helper proteins at intron/exon borders, defining the DNA that will be cut out.
Small nuclear ribonucleo proteins (snRNPs) recognize the splice sites.
A spliceosome is made up of proteins and RNA molecules that splices RNA by interacting with the ends of an RNA intron, releasing the intron and joining the two adjacent exons.
Synthesis of Poly-A tail
Poly-A tail is a stretch of adenine (A) nucleotides.
When a special poly-A attachment site in the pre-mRNA emerges, the transcript is cut there and the poly-A tail is attached to the exposed 3'end.
This completes the mRNA molecule which is ready to be transported to the cytoplasm.
Protein Synthesis Children's Book by Samantha …
In eukaryotes, the termination sites in DNA are present far away from the corresponding actual 3′ end of mRNA, thus, to produce HnRNA (heterogeneous nuclear RNA). The 3′ end of the mRNA is generated after the processing of HnRNA by snurp (small nuclear RNA-protein complex). In addition to these extra nucleotides at 3′ end, the HnRNA may also contain extra nucleotide sequences at the 5′ end and at the internal positions. These extra nucleotide sequences at internal positions are called introns, whereas, the nucleotide sequences in between the introns
Protein Synthesis - Estrella Mountain Community College
that are present in mRNA and contain the information of proteins are known as exons. Thus, HnRNA produced after transcription is quite longer than the mRNA. Most of the extra nucleotide sequences, including introns, are cleaved by snurp. Moreover, after removal of the extra nucleotides from the 3′ end of the HnRNA, poly A tail is added that is required for the stability of the mRNA. Similarly, after removal of extra nucleotides from the 5′ end, a cap of 7-methyl guanosine (7mG) is added that is required for the translation process. The production and processing of HnRNA occurs in the nucleus from where it escapes into the cytoplasm through nuclear pores for the translation process (Fig 8.11 and 8.12).
the actual process of protein synthesis.
RNA polymerase attaches complimentary bases to form an RNA strand.
Comparison of DNA and RNA
Protein Synthesis for Dummies
DNA and RNA are made up of a phosphate group, a 5 carbon sugar, and nitrogenous bases.
DNA's 5 carbon sugar is
RNA's 5 carbon sugar is
DNA nitrogenous bases are adenine,
, guanine, and cytosine.
RNA nitrogenous bases are adenine,
, guanine, and cytosine.
RNA transfers genetic code needed for the creation of proteins from the nucleus to the ribosome.
Just like a builder uses a blueprint to build a house, DNA is used as the blueprint for the organism.