Protein synthesis: Difference between revisions
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= Translation = | = Translation = | ||
'''<u>Componants involved</u>''' | === '''<u>Componants involved</u>''' === | ||
<u>mRNA</u> | <u>mRNA</u> | ||
mRNA is a copy made of the DNA by [[ | mRNA is a copy made of the DNA by [[RNA polymerase II|RNA polymerase II]] and spliced to take out all the introns. This is a single polynucleotide strand that have [[Codon|codons]] made up of [[Adenine|Adenine]], [[Guanine|Guanine]], [[Cytosine|Cytosine]] and [[Uracil|Uracil]] and instead of a [[Deoxyribose sugar|deoxyribose]] in the sugar phospate backbone there is a [[Ribose|ribose]] molecule. <u><br></u> | ||
<u>tRNA</u> | <u>tRNA</u> | ||
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<u>Ribosome</u> | <u>Ribosome</u> | ||
The Ribosome is the location of the translation of proteins, the Ribosome has 3 tRNA binding sites the P site which holds the tRNA molecule with the polypeptide strand, the A site which binds to the tRNA molecule with the next amino acid to by hydrolysed and the E site which holds the tRNA molecule to be discharged<ref>http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect14.htm</ref>. The mRNA strand is attached to the tRNA strand by [[ | The Ribosome is the location of the translation of proteins, the Ribosome has 3 tRNA binding sites the P site which holds the tRNA molecule with the polypeptide strand, the A site which binds to the tRNA molecule with the next amino acid to by hydrolysed and the E site which holds the tRNA molecule to be discharged<ref>http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect14.htm</ref>. The mRNA strand is attached to the tRNA strand by [[Hydrogen bonds|Hydrogen bonds]] and also attached to the ribosome.'''<u><br></u>''' | ||
'''<u></u>''' | '''<u></u>''' | ||
'''<u>The Mechanism</u>''' | === '''<u>The Mechanism</u>''' === | ||
Once the mRNA strand has bound to the <br> | Once the mRNA strand has bound to the <br> | ||
Revision as of 19:44, 15 November 2011
Protein synthesis is the creation of proteins via transcription and then translation on a ribosome, involving RNA polymerase, primers, mRNA, tRNA and rRNA. It occurs in both Eukaryotic and Prokaryotic cells although there are certain differences like splicing occurs in different places and of course there isn't a nucleus in prokaryotes so no movement between membranes is involved to get the mRNA strand out of the cell.
Transcription
Transcription is the copying of DNA in the nucleus into pre-mRNA. For a gene to be synthesised into a protein it needs certain pathways within cells to occur which cause binding of transcription factors to the promoter sequence.
Splicing
Splicing occurs in the nucleus by the use of a spliceosome looping out the introns then cutting them out and binding the exons together leaving a strand of only exons. This is the pre-mRNA maturing and turning into mRNA to leave the cell.
Translation
Componants involved
mRNA
mRNA is a copy made of the DNA by RNA polymerase II and spliced to take out all the introns. This is a single polynucleotide strand that have codons made up of Adenine, Guanine, Cytosine and Uracil and instead of a deoxyribose in the sugar phospate backbone there is a ribose molecule.
tRNA
This is a single polynucleotide strand that folds back on itself to form hydrogen bond in the shape of a clover leaf. This molecule on one end has an anticodon which is complimentary to the codon on the the mRNA strand which it attaches to. On the other end there is a specific protein that is able to detach and form part of a polypeptide chain.
Ribosome
The Ribosome is the location of the translation of proteins, the Ribosome has 3 tRNA binding sites the P site which holds the tRNA molecule with the polypeptide strand, the A site which binds to the tRNA molecule with the next amino acid to by hydrolysed and the E site which holds the tRNA molecule to be discharged[1]. The mRNA strand is attached to the tRNA strand by Hydrogen bonds and also attached to the ribosome.
The Mechanism
Once the mRNA strand has bound to the