Saltar navegación

Activa JavaScript para disfrutar de los vídeos de la Mediateca.

Modificacion proteinas.Golgi

Ajuste de pantalla

El ajuste de pantalla se aprecia al ver el vídeo en pantalla completa. Elige la presentación que más te guste:

Subido el 10 de septiembre de 2010 por Benito H.

876 visualizaciones

Modificacion Retíclo endoplásmico rugoso (RER)

Más información Transcripción

Descargar la transcripción

Proteins targeted to organelles, such as the endosome, cellular membranes, or for extracellular 00:00:08
secretion, must be modified. 00:00:24
The modification is necessary for the correct delivery of the protein to its final cellular 00:00:26
location. 00:00:31
The modification occurs when specific sugar molecules are added to a core oligosaccharide 00:00:32
that is attached to the protein. 00:00:37
These sugar complexes are the signal often required to direct the protein to its final destination. 00:00:40
One example of this is mannose 6-phosphate. 00:00:46
These sugar side chain modifications occur within the Golgi apparatus. 00:00:50
We focus here on the delivery of a hydrolase enzyme to the endosome. 00:00:54
Hydrolases are enzymes that degrade other molecules. 00:00:59
The endosome is an organelle that contains molecules to be degraded. 00:01:02
Other key components include the M6P receptor protein. 00:01:06
So let's follow a hydrolase from the endoplasmic reticulum, or ER, 00:01:10
where it is synthesized, to the endosome. 00:01:16
First, the hydrolase is delivered from the ER to the Golgi apparatus via a vesicle. 00:01:19
While it is being transferred through the ER and cis cisterna of the Golgi apparatus, 00:01:27
the modification of the sugar core oligosaccharide begins. 00:01:35
The term for this process is glycosylation. 00:01:40
Here, we show two steps involved in the production of the mannose 6-phosphate signal. 00:01:43
In humans, defects in Golgi glycosylation can lead to specific diseases. 00:01:49
Once the hydrolase reaches the trans-Golgi cisternae, the mannose 6-phosphate signal has been completed. 00:01:56
Only proteins destined for the endosome have the mannose 6-phosphate signal. 00:02:03
Once modified, the hydrolase is bound to the mannose 6 receptor protein through the mannose 6 phosphate molecule. 00:02:07
The receptor has a domain that extends through the transgolgi membrane. 00:02:15
Through the interaction with this receptor, the hydrolase is associated with the transgolgi membrane. 00:02:20
Next, a vesicle containing the hydrolase buds off from the transgolgi and moves to the endosome. 00:02:26
Endosomes eventually mature into lysosomes. 00:02:33
Other proteins have different sugar side chains and they are delivered to other cellular locations, 00:02:36
or to the cell membrane where it is embedded or secreted. 00:02:42
The vesicle docks and fuses with the endosome. 00:02:46
At this point, the hydrolase is released. 00:02:50
Soon after, the phosphate portion of the mannose 6-phosphate signal is removed. 00:02:54
Before it can go on to degrade other molecules, 00:03:00
the hydrolase will undergo a final modification to become an active enzyme. 00:03:03
The M6P receptors are then recycled back to the Golgi. 00:03:08
The sugar side chain signal added by glycosylation in the Golgi apparatus 00:03:13
is a key element of the process that directs certain proteins to their proper cellular locations. 00:03:18
Valoración:
  • 1
  • 2
  • 3
  • 4
  • 5
Eres el primero. Inicia sesión para valorar el vídeo.
Idioma/s:
en
Autor/es:
Virtual Cell
Subido por:
Benito H.
Licencia:
Reconocimiento - No comercial - Compartir igual
Visualizaciones:
876
Fecha:
10 de septiembre de 2010 - 13:02
Visibilidad:
Público
Enlace Relacionado:
Benito Hernández Giménez
Centro:
IES MORATALAZ
Descripción ampliada:
    En el aparato de Golgi se transforman las sustancias procedentes del RER. Estas transformaciones pueden ser agregaciones de restos de carbohidratos para conseguir la estructura definitiva o para ser proteolizados y así adquirir su conformación activa. en el RER de las células acinosas del páncreas se sintetiza la proinsulina que debido a las transformaciones que sufre en el aparato de Golgi, adquirirá la forma o conformación definitiva de la insulina.
   Las enzimas que se encuentran en el interior de los dictiosomas son capaces de modificar las macromoléculas mediante glicosilación (adición de carbohidratos) y fosforilación (adición de fosfatos). Para ello, el aparato de Golgi transporta ciertas sustancias como nucleótidos y azúcares al interior del orgánulo desde el citoplasma.
Duración:
03′ 50″
Relación de aspecto:
1.31:1
Resolución:
1024x780 píxeles
Tamaño:
22.12 MBytes

Del mismo autor…

Ver más del mismo autor

EducaMadrid, Plataforma Educativa de la Comunidad de Madrid

Plataforma Educativa EducaMadrid