REAGENT or RESOURCE	SOURCE	IDENTIFIER
Antibodies
Rat anti-Foxp3	eBiosciences	PCH101
Mouse anti-Foxp3	eBiosciences	14-7979; RRID:AB_468499
Mouse anti-FLAG	Sigma-Aldrich	F7425; RRID:AB_439687
Mouse anti-hemaglutanin (HA)	Sigma-Aldrich	12CA5; RRID:AB_514505
Rabbit anti-NLK	Santa Cruz	H-100; RRID:AB_2112660
Goat anti-actin	Santa Cruz	I-19; RRID:AB_630836
Anti-HSP90	Cell Signaling	4875; RRID:AB_2233331
Rat anti mouse CD4 (clone RM4-5)	Biolegend	Cat#100536
Rat anti mouse CD62L (clone MEL-14)	Biolegend	Cat#104424
Rat anti CD44 (clone IM7)	Biolegend	Cat#103032
Rat anti mouse CD45Rb (clone 16A)	BD PharMingen	Cat#553101
Rat anti mouse CD25 (clone PC61)	Biolegend	Cat#102016
Mouse anti mouse CD45.1 (clone A20)	eBiosciences	Cat#17-0453-81
Mouse anti mouse CD45.2 (clone 104)	eBiosciences	Cat#12-0454-81
Rat anti mouse CD8 (clone 53-6.7)	Biolegend	Cat#100706
Rat anti mouse CD19 (clone 6D5)	Biolegend	Cat#115538
Rat anti mouse SiglecF (clone E50-2440)	BD PharMingen	Cat#562681
Rat anti mouse Ly6G (clone 1A8)	Biolegend	Cat#127628
Rat anti mouse CD3 (clone 17A2)	Biolegend	Cat#100228
Armenian Hamster anti mouse CD11c (clone N418)	Biolegend	Cat#117334
Rat anti CD11b (clone M1/70)	Biolegend	Cat#101241
Rat anti mouse F4/80 (clone BM8)	eBiosciences	Cat#25-4801-82
Rat anti mouse MHCII (I-A/I-E) (clone M5/114.15.2)	eBiosciences	Cat#47-5321-82
Mouse anti mouse NK-1.1 (clone PK136)	Biolegend	Cat#108710
Rat anti FoxP3 (clone FJK-16 s)	eBiosciences	Cat#50-5773-82
Chemicals, Peptides, and Recombinant Proteins
Phos-tag acrylamide	WAKO Chemicals GmbH	300-93523
DMEM containing GlutMax	GIBCO Life Technologies	31966047
RPMI 1640	GIBCO Life Technologies	61870044
IMDM	GIBCO Life Technologies	12440-061
FBS	GIBCO Life Technologies	S1810-500
Penicillin-Streptomycin	GIBCO Life Technologies	15140-122
Nonidet p40	US Biologicals	N3500
HALT protease inhibitor cocktail	Thermo Scientific	78439
Anti-HA conjugated beads	Sigma-Aldrich	A2095
PVDF	Millipore	IPFL00010
iScript cDNA synthesis kit	BioRad	170-8891
Poly-L-lysine	Sigma-Aldrich	P4707
Anti-CD3/CD28 Dynabeads	ThermoFisher	11452D
TGF-β	R&D systems	240-B-010
RNasin inhibitor	Promega	N2111
dNTPs	Promega	28-4065-60
Oligo dT15	Promega	C1101
PEI	Polysciences	23966-1
PKB inhibitor VII	Calbiochem	124018
5Z-7-oxozeanol	Tocris Biosceince	3604/1
BIO	Tocris Biosceince	3194/1
γPPAse	New England Biolabs	P0753s
GST-NLK	Sigma-Aldrich	SRP5285
Okadaic acid	Enzo Lifesciences	ALX-350-003-C050
SB203580	Enzo Lifesciences	BML-EI286-001
SP600125	Enzo Lifesciences	BML-EI305-010
Rapamycin	Enzo Lifesciences	A275-0005
U0126	Enzo Lifesciences	BML-EI282-0001
Cycloheximide	Sigma-Aldrich	C4859
Critical Commercial Assays
Foxp3 staining kit	eBioscience	00-5521-00
Proximity Ligation Assay kit	Sigma-Aldrich	DUO92101
Live/dead kit	Life Technologies	L3224
CellTrace Violet tracker	ThermoFisher	C34557
Deposited Data
Raw and analyzed Mass Spectrometry Data	This paper	PRIDE: PXD011164
Experimental Models: Cell Lines
HEK293	ATCC	CRL-11268
Experimental Models: Organisms/Strains
Mouse: C57BL/6	Internal breeding colonies of the University of Edinburgh or of the University of Utrecht	N/A
Mouse: BALB/c	Internal breeding colonies of the University of Edinburgh or of the University of Utrecht	N/A
Mouse: NLKfl/fl	The Jackson Laboratory	JAX: 024537 B6;129-Nlktm.1.1Ecan/J
Mouse: Foxp3CRE	The Jackson Laboratory	JAX: 016959 B6.129(Cg)-Foxp3 tm4(YFP/icre)Ayr/J
Mouse: Foxp3-eGFP	The Jackson Laboratory	JAX: 006772 B6.Cg-Foxp3 tm2(EGFP)Tch/J
Oligonucleotides
See Table S1		N/A
Recombinant DNA
pMT2-HA_Foxp3	van Loosdregt et al., 2013b	N/A
pMT2-HA_JNK	de Groot et al., 1997	N/A
pMT2-HA_ERK	de Groot et al., 1997	N/A
pMT2-His_Ubi	van Loosdregt et al., 2013a	N/A
pMT2-myc_USP7	van Loosdregt et al., 2013a	N/A
pMT2-myc_FoxP3	van Loosdregt et al., 2013a	N/A
pLP/VSVG	van Loosdregt et al., 2013a	N/A
psPAX2	van Loosdregt et al., 2013a	N/A
pMT2-FLAG_NLK	Szypowska et al., 2011	N/A
pLKO.1 puro NLK human shRNA	Sigma-Aldrich	TRCN0000002071
pLKO.1 puro NLK human shRNA	Sigma-Aldrich	TRCN0000195090
pRFP-C-Rs Nlk shRNA	OriGene Technologies	TF501483
Stub1	Harvard Medical School	HsCD00326610
pUC57 Foxp3 7xA and 7x	Genescript Biotech	Custom synthesis
Software and Algorithms
FlowJo 10	FLOWJO, LLC	https://www.flowjo.com/