What I learned today...intracellular vesicular traffic

Today's cell biology class was very interesting to say the least. It entailed protein shuttling via vesicular transport. In short, this is pretty much the packaging of proteins (cargo) into little round spherical balls (transport vesicles) that go from one compartment of the cell to another. Proteins can be transported in three different way within the cell. They include: gated transport, transmembrane transport and vesicular transport. Vesicular transport looked easy at first glance but it involves many complexities. They mainly arise from the mechanisms involved in creating the vesicle. In this type of transport we see "vesicles"bud off from donor membrane to recipient membranes. These vesicles come in three different forms: small vesicles, large vesicles and tubular vesicles. Each one being very specialized in what route it takes to get to its destination. This specificity comes from the transport vesicles highly specific coated region. This coat is assembled from the donor membrane and also collects specific membrane soluble cargo molecules for transport.  The coats that are assembled in these transport vesicles are variable. 

The three most recognized though are: COP1, COP2 and the clathrin coat. Each have a specific transport route. The clathrin coat was the first and best understood coat. This coat directs its transport vesicle from the plasma membrane and the trans golgi network. Adaptor proteins play another major role in the formation of the clathrin coat. They form a 2nd layer coat the lie between the membrane and the clathrin protein.