Transcript Central Dogma

Translation of mRNA into a polypeptide
 http://vcell.ndsu.edu/animations/translation/movie-
flash.htm
 http://highered.mcgrawhill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/si
tes/dl/free/0072437316/120077/micro06.swf::Protein
Synthesis
 Translation is the synthesis of a protein from an mRNA
template.
 This process involves several key molecules:
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
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mRNA
the small and large subunits of the ribosome
tRNA
the release factor
 The process is broken into three stages:
 initiation
 elongation
 termination
 tRNA contains an anticodon that is complementary to
the mRNA codon to which it binds.
 Attached to the end of tRNA is the corresponding
amino acid
 The first codon is typically AUG.
 Methionine corresponds to the AUG codon.
http://www.wiley.com/college/boyer/0470003790/structure/tRNA/trna_intro.htm
http://www.wiley.com/college/pratt/0471393878/student/structure/trna_aars/index.html
 Translation initiation
begins when the small
subunit of the ribosome
attaches to the 5 ´end of
the mRNA and moves to
the translation initiation
site.
 The large ribosomal
subunit now binds to
the small ribosomal
subunit to create the
peptidyl (or P) site and
the aminoacyl (or A)
site.
 The first tRNA
occupies the P-site.
 The second tRNA
enters the A-site
 The methionine is transferred to the A-site amino acid
 the first tRNA exits
 the ribosome moves along the mRNA
 the next tRNA enters
http://www.tutorvista.com/content/biology/biology-iii/gene-expression/proteins-synthesis-mechanism.php
 the growing peptide is continually transferred to the
A-site tRNA
 the ribosome moves along the mRNA
 new tRNAs enter
 When a stop codon
is encountered in
the A-site, a release
factor enters the Asite and translation
is terminated.
 When termination
is reached, the
ribosome
dissociates, and the
newly formed
protein is released.
 http://learn.genetics.utah.edu/content/begin/dna/tra
nscribe/