As said before, Receptors are used to transfer data between cells. In principle, NetBuilder Receptors can be used to represent any process in which signals get exchanged between cells, even those that do not actually involve biological cell surface receptors.
NetBuilder offers a choice of two mechanisms for intercellular signalling:
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Local signalling A signal is sent from one specified cell to one or more other cells |
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Global signalling A signal is released into the intracellular medium, and picked up by all cells that have active receptors for the signal |
There are some subtle differences between these mechanisms, and the choice will depend on the process that is being modelled.
To define intercellular pathways, select the receptor whose contacts you want to define, and press the Contacts button on the Design toolbar. A dialog box will pop up:
If you change the signalling mechanism from local to global, the dialog box looks like this:
Choose Local signalling (top dialog box), and model intercellular signalling so that the signal goes from cell A to cell B1, from there to cell B2 and B3, and from B2 back to A. Thus, select cell A in the donor cell list, and B1 in the available cells list, and press the Add button. Then select B1 as the donor cell, and add B2 and B3 from the available cells to the receiving cells. Finally, select B2 as a donor, and add A as a receiving cell. Press OK to confirm, and to quit the dialog.
The donor-receptor interactions are now set.