Week Number: 10
Seminar Date: Wednesday 11th October
Time: 10am-11am
Module: Cell Biology BI503
Intercellular transport
Dr Hargreaves research Project:
Monoclonal antibodies- research topic. Used to treat autoimmune disease, cancer.
Economically wealthy countries have access to these, but others don’t. The reason they are
expensive is because we must make them using cells. Goal is to make them cheaper, to do
that we need to understand the secretory pathway.
If you are interested in nuclear transport or other pathways, then you can explore this in your
textbook.
All slides have alt text – this will cover the lecture information.
Eukaryotic cells have membrane enclosed in organelles.
In a bacterium cell, proteins move through the cytoplasm, whereas in larger cells it is
impossible for this to happen.
à Membranes
o Barrier to separate contents of organelles from the rest of cytoplasm
o Selectively permeable
o Increase surface area for biochemical reactions.
à Organelles
o Each contain a unique set of proteins.
o Concentrate subsets of molecules
Not all cells are the same. In some cells we turn on some sets of genes (i.e. histone,
chromatin etc), other cells express more types of genes i.e. a plasma cell has more
endoplasmic reticulum.
Following the secretory pathway – this will be picked up with Dr Gourlay later.
o ER – Endoplasmic reticulum.
o 50 % of cellular membrane is in the ER.
o Rough ER (has ribosomes attached to it) Vs smooth ER (does not have ribosomes)
Why do we cover ER in Ribosomes? We need lots of proteins in the ER, this is done using
membrane bound ribosomes. The translation starts in the cytosol, which has a signal
sequence in the growing polypeptide chain that tells the ribosome that the protein needs to
be transferred to the ER. At this point it will be signaled to dock and feed the protein into the
1
Seminar Date: Wednesday 11th October
Time: 10am-11am
Module: Cell Biology BI503
Intercellular transport
Dr Hargreaves research Project:
Monoclonal antibodies- research topic. Used to treat autoimmune disease, cancer.
Economically wealthy countries have access to these, but others don’t. The reason they are
expensive is because we must make them using cells. Goal is to make them cheaper, to do
that we need to understand the secretory pathway.
If you are interested in nuclear transport or other pathways, then you can explore this in your
textbook.
All slides have alt text – this will cover the lecture information.
Eukaryotic cells have membrane enclosed in organelles.
In a bacterium cell, proteins move through the cytoplasm, whereas in larger cells it is
impossible for this to happen.
à Membranes
o Barrier to separate contents of organelles from the rest of cytoplasm
o Selectively permeable
o Increase surface area for biochemical reactions.
à Organelles
o Each contain a unique set of proteins.
o Concentrate subsets of molecules
Not all cells are the same. In some cells we turn on some sets of genes (i.e. histone,
chromatin etc), other cells express more types of genes i.e. a plasma cell has more
endoplasmic reticulum.
Following the secretory pathway – this will be picked up with Dr Gourlay later.
o ER – Endoplasmic reticulum.
o 50 % of cellular membrane is in the ER.
o Rough ER (has ribosomes attached to it) Vs smooth ER (does not have ribosomes)
Why do we cover ER in Ribosomes? We need lots of proteins in the ER, this is done using
membrane bound ribosomes. The translation starts in the cytosol, which has a signal
sequence in the growing polypeptide chain that tells the ribosome that the protein needs to
be transferred to the ER. At this point it will be signaled to dock and feed the protein into the
1
