TABLE 1:

Activities of FAM21 tail constructs.

Name	Sequence	Relative binding to retromer CSC	Stoichiometry (N) by ITC	Kd (μM) by ITC	Endosomal localization
FN	356–600	++	0.32 ± 0.23	11.5 ± 3.8
FC	938–1341∆1029–1047	+++	0.42 ± 0.04	2.4 ± 0.6
FC*	938–1341				–
FM	601–900	+
R17	1186–1221	–
R20	1280–1317	+
R21	1309–1341	+	0.82 ± 0.24	16.6 ± 4.3
R17-18	1186–1254	–
R19-20	1250–1317	+++	0.39 ± 0.12	6.8 ± 1.4
R20-21	1278–1341	+++	0.49 ± 0.02	2.5–16.6a
R17-19	1186–1285	+
R17-20	1186–1317	+++
R17-21	1186–1341	+++
R15-20	1121–1317	+++
No R	938–1120	–
R5-21	496–1341				+++
R6-21	549–1341				+
R7-21	594–1341				+/–
R9-21	675–1341				+/–
R11-21	743–1341				–
R5-20	496–1309				+/–
R5-19	496–1275				–
R1-19	357–1275				+
R5-21/ΔR11-14	496–1341/Δ803–888				+/–
Fusion FC*/ R11-21	938–1341/743–1341 fusion				+++

1/N is the number of retromer CSCs bound to each Fam21 fragment.

^aSee Materials and Methods for explanation of range.