sin tes is protein as
TRANSCRIPT
-
8/20/2019 Sin Tes is Protein As
1/39
El Dogma Central de la Biología Molecular describe un proceso de
dos pasos, la transcripción y la traducción , por el cual la información
contenida en los genes se transforma en proteínas.
ADN ARN proteínas
-
8/20/2019 Sin Tes is Protein As
2/39
TRANSCRIPCION
TRADUCCION
DNA
mRNA
Ribosoma
Polipeptido
DNA
Pre-mRNA
celula procariotica
Envoltura
Nuclear
mRNA
TRADUCCION
TRANSCRIPTION
PROCESAMIENTO RNA
Ribosoma
Polipeptido
Eukaryotic cell
-
8/20/2019 Sin Tes is Protein As
3/39
TRANSCRIPCIONDNA
TRADUCCION
Ribosoma
Polipeptido
mRNA
Celula Procariotica
-
8/20/2019 Sin Tes is Protein As
4/39
LE 17-3-5
TRANSCRIPTION
TRANSLATION
DNA
mRNA
Ribosome
Polypeptide
DNA
Pre-mRNA
Prokaryotic cell
Nuclear
envelope
mRNA
TRANSLATION
TRANSCRIPTION
RNA PROCESSING
Ribosome
Polypeptide
Eukaryotic cell
-
8/20/2019 Sin Tes is Protein As
5/39
DNA
molecula
Gen 1
Gen 2
Gen 3
DNA cadena
(templada)
3
TRANSCRIPCION
Codon
mRNA
TRADUCCION
Proteina
Amino acido
3
5
5
-
8/20/2019 Sin Tes is Protein As
6/39
Elongacion No-templadaCadena devDNA
RNA
polimerasa
RNA nucleotidos
3 end3
5
5
Nuevo RNA
Cadena templado
ADN
Direccion de transcripcion
(“downstream”)
Promotor
5 3
RNA polimerasa
Punto de iniciacion
DNA
Unidad Transcripcion
3 5
5 3
3 5
Unwound
DNA
RNA
tran-
script
Template strand
of DNA
Iniciacion
Elongacion
Terminacion
5 3
3 5
5 3
3 5
3 5
Rewound
DNA
RNA
transcripto
5
Completo RNA transcript
-
8/20/2019 Sin Tes is Protein As
7/39
LE 17-8
Promoter
5 3
3 5
TATA box Start point
Transcription
factors
5
3 3
5
Several transcriptionfactors
Additional transcription
factors
RNA polymerase II Transcription factors
RNA transcript
5
3
3
5
5
Transcription initiation complex
Eukaryotic promoters
Template
DNA strand
-
8/20/2019 Sin Tes is Protein As
8/39
-
8/20/2019 Sin Tes is Protein As
9/39
LE 17-11
Exon 15
Intron Exon 2
Other proteins
Protein
snRNA
snRNPs
RNA transcript (pre-mRNA)
Spliceosome
5
Spliceosome
componentsCut-out
intron
mRNA
Exon 1 Exon 2
5
-
8/20/2019 Sin Tes is Protein As
10/39
Exon 15
Intron
Otras proteinas
Proteina
snRNA
snRNPs
RNA transcripto (pre-mRNA)
Spliceosoma
Exon 2
-
8/20/2019 Sin Tes is Protein As
11/39
5
Spliceosoma
Corte-out
intron
mRNA
Exon 1 Exon 2
5
componentes
Spliceosoma
-
8/20/2019 Sin Tes is Protein As
12/39
-
8/20/2019 Sin Tes is Protein As
13/39
Gen
Transcripcion
Procesamiento RNA
Traduccion
Dominio 2
Dominio 3
Dominio 1
Polipeptido
Exon 1 Intron Exon 2 Intron Exon 3
DNA
LE 17 9
-
8/20/2019 Sin Tes is Protein As
14/39
LE 17-9
5
Protein-coding segment
5 Start codon Stop codon Poly-A tail
Polyadenylation signal
5 3 Cap UTR UTR
LE 17 10
-
8/20/2019 Sin Tes is Protein As
15/39
LE 17-10
5 Exon Intron Exon Intron Exon 3
Pre-mRNA
1 30 31 104 105 146
Coding
segment
Introns cut out and
exons spliced together
1 146
5 Cap
5 Cap
Poly-A tail
Poly-A tail
5 3 UTR UTR
-
8/20/2019 Sin Tes is Protein As
16/39
Codón iniciación Codón StopCodón
Cola
(no traducido)Fragmento lectura
(traducido)
Guía
(no traducido)
LE 17 13
-
8/20/2019 Sin Tes is Protein As
17/39
LE 17-13
Polypeptide
tRNA with
amino acid
attached
Ribosome
tRNA
Anticodon
3
5
mRNA
Amino
acids
Codons
-
8/20/2019 Sin Tes is Protein As
18/39
Sitio de union
Amino acido
Puentes
Hydrogeno
3
5
estructura dos dimensionesAnticodon
Sitio de union
Amino acido
3 5
Puentes
Hidrogeno
Anticodon Anticodon
Simbolo usadoEstructura tres dimensiones
3 5
-
8/20/2019 Sin Tes is Protein As
19/39
Amino acidoAminoacil-tRNA
sintetasa (enzima)
Pirofosfato
Fosfatos
tRNA
AMP
Aminoacil tRNA
(un “activado
amino acido”)
-
8/20/2019 Sin Tes is Protein As
20/39
sitio P (Sitio ligadura
Peptidil-tRNA)
sitio E
(sitio salida)
Sitio ligadura
mRNA
Sitio A (sitio de ligadura
Aminoacyl-tRNA)
Subunidad
mayor
Subunidad
menor
Schematic model showing binding sites
E P A
LE 17-5
-
8/20/2019 Sin Tes is Protein As
21/39
LE 17-5
Second mRNA base
T h i r d m R N A b a s e
( 3
e n d )
LE 17-16
-
8/20/2019 Sin Tes is Protein As
22/39
LE 17 16
Amino end
mRNA
5
3
Growing polypeptide
Next amino acidto be added topolypeptide chain
tRNA
Schematic model with mRNA and tRNA
Computer model of functioning ribosome
5
3
E
Codons
Schematic model showing binding sites
Small
subunit
Large
subunit
A site (Aminoacyl-
tRNA binding site)E site
(Exit site)
E P A
mRNA
binding site
P site (Peptidyl-tRNA
binding site)
Smallsubunit
Large
subunit
Exit tunnelGrowing
polypeptidetRNA
molecules
E P A
mRNA
LE 17-16a
-
8/20/2019 Sin Tes is Protein As
23/39
LE 17 16a
tRNA
molecules
Exit tunnel
Growingpolypeptide
Large
subunit
mRNA 3
Computer model of functioning ribosome
Small
subunit
5
E P A
INICIACION
-
8/20/2019 Sin Tes is Protein As
24/39
INICIACION
GTPInitiator tRNA
mRNA
5
3
mRNA binding site
Small
ribosomalsubunit
Start codon
P site
5
3
Translation initiation complex
E A
Largeribosomal
subunit
GDP
LE 17-16c
-
8/20/2019 Sin Tes is Protein As
25/39
LE 17 16c
Amino end
mRNA
5
3
Growing polypeptide
Next amino acid
to be added to
polypeptide chain
tRNA
Codons
Schematic model with mRNA and tRNA
E
ELONGACION
-
8/20/2019 Sin Tes is Protein As
26/39
Ribosome ready for
next aminoacyl tRNA
mRNA
5
Amino end
of polypeptide
E
Psite
Asite
3
2
2 GDP
E
P A
GTP
GTP
GDP
E
P A
E
P A
-
8/20/2019 Sin Tes is Protein As
27/39
TERMINACION
-
8/20/2019 Sin Tes is Protein As
28/39
Release
factor
Stop codon
(UAG, UAA, or UGA)
5
3
5
3
5
Free
polypeptide
3
When a ribosome reaches a stop
codon on mRNA, the A site of theribosome accepts a protein called
a release factor instead of tRNA.
The release factor hydrolyzes the
bond between the tRNA in theP site and the last amino acid of the
polypeptide chain. The polypeptide
is thus freed from the ribosome.
The two ribosomal subunits
and the other componentsof the assembly dissociate.
-
8/20/2019 Sin Tes is Protein As
29/39
LE 17-20
-
8/20/2019 Sin Tes is Protein As
30/39
Ribosomes
mRNA
This micrograph shows a large polyribosome in a prokaryotic cell (TEM).
An mRNA molecule is generally translated simultaneously
by several ribosomes in clusters called polyribosomes.
Incoming
ribosomal
subunits
Growing
polypeptides
End of mRNA(3 end)
Start of mRNA(5
end)
Completed
polypeptides
m0.1
LE 17-20a
-
8/20/2019 Sin Tes is Protein As
31/39
Incoming
ribosomal
subunits
Growing
polypeptides
Completed
polypeptide
Start of
mRNA
(5 end)
End of
mRNA(3
end)
An mRNA molecule is generally translated simultaneously
by several ribosomes in clusters called polyribosomes.
-
8/20/2019 Sin Tes is Protein As
32/39
LE 17-20b
-
8/20/2019 Sin Tes is Protein As
33/39
Ribosomes
mRNA
This micrograph shows a large polyribosome in a prokaryotic cell (TEM).
m0.1
LE 17-21
-
8/20/2019 Sin Tes is Protein As
34/39
Ribosomes
mRNA
Signal
peptide
Signal-
recognition
particle
(SRP)SRP
receptor
protein
CYTOSOL
ER LUMEN Translocation
complex
Signalpeptide
removed
ER
membrane
Protein
LE 17-22
-
8/20/2019 Sin Tes is Protein As
35/39
RNA polymerase
DNA
Polyribosome
RNA
polymerase
Direction of
transcription
mRNA
0.25
DNA
Polyribosome
Polypeptide
(amino end)
Ribosome
mRNA (5
end)
m
-
8/20/2019 Sin Tes is Protein As
36/39
Las bases moleculares de la enfermedad anemia falci forme
Hemoglobina DNA normal
mRNA
3 5 5 3
5 3 3 5
Hemoglobina DNA mutante
mRNA
Hemoglobina normal Sickle-cell hemoglobin
Cualquier cambio en la secuencia de los nucleótidos del ADN se denominaMUTACION
normal
-
8/20/2019 Sin Tes is Protein As
37/39
substitucion par-base
No afecta la secuencia de aminoacidos
U en lugar de C
Missense
A en lugar de G
NonsenseU en lugar de A
Stop
Amino terminal
Proteina
5
3
Carboxyl terminal
Stop
Stop
Stop
mRNA
normal
Wild type
-
8/20/2019 Sin Tes is Protein As
38/39
Insercion o perdida de un par -base
Frameshift causing immediate nonsense
Extra U
Missing
Frameshift causing
extensive missense
Insertion or deletion of 3 nucleotides:
no frameshift but extra or missing amino acid
Missing
Stop
Stop
Amino terminal Carboxyl terminal
Stop
Wild type
mRNA
Protein
5
3
-
8/20/2019 Sin Tes is Protein As
39/39
TRANSCRIPTION
RNA PROCESSING
RNAtranscript
5
Exon
NUCLEUS
FORMATION OFINITIATION COMPLEX
CYTOPLASM
3
DNA
RNApolymerase
RNA transcript(pre-mRNA)
Intron
Aminoacyl-tRNAsynthetase
Aminoacid
tRNA
AMINO ACID ACTIVATION
3
mRNA
A
P
E Ribosomalsubunits
5
Growingpolypeptide
E A
Activatedamino acid
Anticodon
TRANSLATION
Codon
Ribosome