Application of Forster resonance energy transfer to interactions between cell or lipid vesicle surfaces

Vol. 88, No. 1, 1979

BIOCHEMICAL

AND BIOPHYSICAL RESEARCH COMMUNICATIONS

May 14, 1979

Pages

OF FORSTER RESONANCE ENERGY TRANSFER TO INTERACTIONS BETWEEN CELL OR LIPID VESICLE SURFACES’

APPLICATION

George

March

19,

A. Gibson

and Leslie

M. Loew2

Department of Chemistry University of New York at Binghamton Binghamton, New York 13901

State

Received

141-146

1979

SUMMARY Calculations are presented which demonstrate the efficacy of a F6rster resonance energy transfer technique to measurement of the aggregation of cells and lipid vesicles.

INTRODUCTION The use of Fiirster tance

between

resonance

chromophores

of fluorescence

energy

and acceptor,

is

energy a well

transfer,

R, according

(1)

established

kT,

to the

transfer

is

technique

related

following

to measure (2).

to distance

the disThe rate

between

donor

equation:

(1) where

T is

distance

the

at which

In the which

total

lifetime

of the

fluorescence

preceding

paper

(3)

can be used to measure

transfer.

Here

we demonstrate

to measure

long

range

have

chosen

a unilamilar the

is

area

two cases vesicle

of

contact

we introduced vesicle that

between

fusion this between

analysis:

suspension;

excited

state

the and the

a donor

a pair

of fluorescent

correspondence

the

probes

by FZrster

resonance

energy

same technique

has the

potential

vesicle

or cell

measurement

surfaces.

of fluorescence

measurement

of fluorescence

labeled and an acceptor

'Supported by grants from the New York State Health and The National Cancer Institute (CA 23838). 2Address

and R, is

50% quenched.

interactions for

donor

Research

We from from

labeled cell (4). Council

(# 362)

to LML. 0006-291X/79/090141-06$01.00/0 141

Copyright All rights

@ 1979 by Academic Press, Inc. ofreproduction in any form reserved.

BIOCHEMICAL

Vol. 88, No. 1, 1979

Fiqure energy sphere,

AND RIOPHYSICAL RESEARCH COMMUNICATIONS

R*=ri

-2r2

T*=rf

-2r,

Tcos02+T2 ScosO,

+S*

1. Definition of geometrical parameters transfer between a donor labeled sphere,

used in the calculation of I, and an acceptor labeled

II.

RESULTS AND DISCUSSION We have chosen taining

randomly

II,

other,

to model distributed

containing the

arbitrary

on surface

point

where

oA is the I(ngstroms.

square

This

t4)

kT = ( rate

rate

energy

distribution constant

I will

as two spheres, donor

probes,

of acceptor for

be given

transfer

one conI,

probes

and the (Figure

from a donor

1).

at an

as

j12=D

Re6 sine2de2

.

surface

density

of acceptor

probes

This

integral

T

2nr

(3)

total

2nr 2R 6d 2 o A

kT =

vesicles

fluorescence

a similar

We can see that

(2)

aggregating

2R 6~ 2T ' A )((T-P~)-~

constant

4 = k,

is

then

can be evaluated

- (T+r2)-4)

used to compute

on II in reciprocal to yield

.

a quantum

yield

kf

+ ,,,

nr + kT

which

must,

donor

sphere:

itself,

be integrated

over

142

the normalized

surface

area

of the

BIOCHEMICAL

Vol. 88, No. 1, 1979

AND BIOPHYSICAL RESEARCH COMMUNICATIONS

I 10 Surface

to

Surface

Separation

1

A’ )

( in

Figure 2. Calculated quantum yield for 250 I( vesicles where the donor has a 'I = 6 x O-g set (as does dansyl-DPPE) and the quencher surface density is lo- 4 d. Th e c h romophores are assumed to be localized at the vesicle surface.

kfr12sineldel

1 <$> = 4nrl2

(5)

kf and k,,

are

the excited

the

donor,

I rate

of the relative

surface

separation.

even occur

(5)

sion

spectra

another of cell-cell

type

for

radiative

Numerical yield

The results

are

amounts

where

(40-70

The vesicle

constants

quantum

measurable

at distances

kf + knr + kT

respectively.

diction

can produce

el=O

integration

as a function displayed

of quenching

a long

and non-radiative

range

of (5)

2.

attainable

intermembrane

allows

of R, and surface

in Figure for

decay

This values

potential

of preto

technique of

minimum

R.

may

W). aggregation

from

bulk

phospholipid

of experiment adhesion.

experiment

which

would

involve

dispersions. would

A fluorescence

extend

We can, this

microscope

143

measurement however,

technique could

of emisenvisage

to the study

be used to focus

Vol. 88, No. 1, 1979

BIOCHEMICAL

AND BIOPHYSICAL RESEARCH COMMUNICATIONS

I

II R

1Dtan8

D

::

cos 0

Fiqure energy surface

3. Definition of geometrical parameters transfer between adjacent cell surfaces. and II is the acceptor labeled surface.

on the

interacting

to the

fluorescence

In the several

surfaces from

case of aggregating

microns--a

have,

distance

therefore,

(Figure

3).

chosen In this

case

I e=O

T can be solved

analytically

the

cells,

opposed

surfaces

respect

to the

with this

of

contribution

each other.

as two opposing

can extend

for

FGrster

process.

infinite

planes

We

integral:

*/2

kT =

eliminating

from

large

the

two cells

used in the calculation I is the donor labeled

remote

to model

2nD 2aARo 6

(6)

of the areas

D

R=-

Rm6 tane

d(tane)

to give:

6 'AXRo

(7) It

kT = 2 is

the

T

interesting

distance

with

the

a different

from

only

in quantum

in R, is

concentration

the

in this

form

inverse

to inverse

approach,

yield

this

A similar

of fluorescent

differing

that

process,

distance.

Calculation

surface

dependence

Fiirster

interplane using

to note

in their

displayed case

sixth

fourth

result

quantum

shows a reduction order,

order

yields in Figure

is quite

of acceptor.

144

of stacked for

three 4.

normally

associated

in D, the perpendicular

was obtained study

in the order

by Biicher

et al.

(2a)

dye monolayers. systems

of probes

The predicted

reduction

dramatic-even

at relatively

low

of

BIOCHEMICAL

Vol. 88, No. 1, 1979

AND BIOPHYSICAL

RESEARCH COMMUNICATIONS

0 0

Surface to Surface Separation

II

( in 8, )

quantum yield for 2 adjacent cell Figure 4. Calculated donor parameters (4 = 0.3, T = 6 x 10-9 set) are those and the acceptor surface density (a,) is 10-4 lN2.

In each experimental to preclude the

mixing

probes

Fiirster

should

however, in the

of the be held

pair

experiments

near

must

be tightly

the

surface

of the membrane-to

conditions

are well

in the preceeding

pairs

(6)

paper

by the above

to facilitate

bound

Further, maximize

satisfied (3).

low R, (36 1) and so we are currently

of other

suggested

probes

by dissociation-association.

of these

introduced

has a relatively evaluation

probes

Both

interaction.

donor-acceptor

case the fluorescent

surfaces. The of dansyl-DPPE

the

by the

This

pair, involved

performance

of the

progranmring

assistance.

calculations.

ACKNOWLEDGEMENT We would

like

to thank

Dr.

Robert

Stuckart

for

REFERENCES 1.

Farster, von T. (1949) Disc. Faraday Sot. 27,

Z. Naturforsch. 7.

145

4a,

321;

FSrster,

von T.

(1959)

Vol. 88, No. 1, 1979

2.

3. 4. 5. 6.

BIOCHEMICAL

AND BIOPHYSICAL RESEARCH COMMUNICATIONS

Representative examples include a) Biicher, H., Drexhage, K.H., Fleck, M., Kuhn, H., Mobius, D., Schafer, F.P., Sondermann, J., Sperling, W., Tillman, P., and Weingand, J. (1967) Molec. Crystals 2, 199; b) Wu, C.-W., and Stryer, L. (1972) Proc. Nat. Acad. Sci. USA 69, 1104; c) Stryer, L., and Thomas, D.D. (1978) Proc. Nat. Acad. Sci. USA 75, 5746. Biophys. Res. Comm., preGibsori, G-A., and Loew, L.M. (1979) Biochem. ceding paper in this issue. J. 25, 260a. Gibson, G.A., and Loew, L.M. (1979) Biophys. Parsegian, V.A., and Gingell, D. (1972) J. Adhesion 4, 283. Gibson, G.A, (1978) Biophys. J. 24, 126a.

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