Rockefeller University Press

Table I

Summary of the Theoretical Predictions for FRET for Various Distributions of Donor- and Acceptor-labeled Molecules in Membranes

Test	Predictions for
Test	Randomly distributed molecules^*	Mixture of clustered and randomly distributed molecules^‡	Clustered molecules^§
1. E is dependent on acceptor	yes	yes	no
surface density
2. E is dependent on donor	no^‖	no	no
surface density
3. E goes to zero at low	yes	sometimes	no
surface densities
4. E is sensitive to the donor:	no^¶	yes	yes
acceptor ratio

Test	Predictions for
Test	Randomly distributed molecules^*	Mixture of clustered and randomly distributed molecules^‡	Clustered molecules^§
1. E is dependent on acceptor	yes	yes	no
surface density
2. E is dependent on donor	no^‖	no	no
surface density
3. E goes to zero at low	yes	sometimes	no
surface densities
4. E is sensitive to the donor:	no^¶	yes	yes
acceptor ratio

See Appendix for a detailed discussion of each case, including any additional assumptions or limitations.

Derived from Eqs. A1 and A2 and illustrated in Fig. A2.

Derived from Eq. A5 and illustrated in Fig. A3.

Derived from Eq. A4.

In the limit where excited state donors do not compete for acceptors.

So long as the acceptor concentration is kept constant.