REAGENT or RESOURCE	SOURCE	IDENTIFIER
Antibodies
Mouse monoclonal anti-BRCA1	Santa Cruz Biotechnology	Cat# sc-6954; RRID: AB_626761
Rabbit anti-MDC1	Abcam	Cat# ab11171; RRID: AB_297810
Rabbit anti-RAP80	Bethyl Laboratories	Cat# A300-764; RRID: AB_2779443
Mouse anti-GFP	Roche	Cat# 11814460001; RRID: AB_390913
Mouse anti-tubulin	Sigma-Aldrich	Cat# T6199; RRID: AB_477583
Rabbit anti-SHMT2	Sigma-Aldrich	Cat# SAB1100388; RRID: AB_10610173
Rabbit anti-ABRO1	Abcam	Cat# ab74333; RRID: AB_1280902
Alexa Fluor 488-conjugated donkey anti-rabbit antibody	ThermoFisher	Cat# R37118; RRID: AB_2536183
Bacterial and Virus Strains
Escherichia coli BL21-CodonPlus (DE3)-RIL	Agilent Technologies	Cat# 230245
Chemicals, Peptides, and Recombinant Proteins
SigmaFast protease inhibitor cocktail	Sigma-Aldrich	Cat# S8820
Strep-Tactin resin	iba	Cat# 2-1201-025
TEV protease	This paper	N/A
Human and mouse BRCA1-A complexes	This paper	N/A
Human and mouse BRISC complexes	This paper	N/A
K63-linked di-ubiquitin (K63-diUb)	Emma Branigan, Ronald T. Hay	N/A
SUMO-2-K63-(Ub)2	Emma Branigan, Ronald T. Hay	N/A
K63-(Ub)2	Boston Biochem	Cat# UC-300B
K63-(Ub)3	Boston Biochem	Cat# UC-315B
K63-(Ub)4	Boston Biochem	Cat# UC-310B
peptide p-Ser404 (GGGFGEYpSRSPTF)	Biomatik	Custom synthesis
Peptide p-Ser406 (GGGFGEYSRpSPTF	Biomatik	Custom synthesis
peptides p-Ser404/406 (GGGFGEYpSRpSPTF)	Biomatik	Custom synthesis
BirA enzyme	This paper	N/A
MitoTracker Red CMXRos	Thermo Fisher Scientific	Cat# M7512
Alexa Fluor 633-conjugated wheat germ agglutinin	Thermo Fisher Scientific	Cat# W21404
K63-(Ub)4, TAMRA label on proximal ubiquitin	LifeSensors	Cat# SI6304T
K63-(Ub)4, TAMRA label on distal ubiquitin	Boston Biochem	Custom synthesis
Critical Commercial Assays
IQF DiUb K63 assay	Life Sensors	Cat# DU0102, DU6301
Deposited Data
Original image files	This paper; Mendeley Data	https://dx.doi.org/10.17632/8ntswhp8d5.1
Structure of BRCA1-A complex	This paper	PDB: 6GVW
Map of BRISC-SHMT2 complex	This paper	EMDB: EMDB-0132
Structure of BRISC-SHMT2 complex	This paper	PDB: 6H3C
PLP-bound SHMT2 structure	Giardina et al., 2015	PDB: 5V7I
Apo-SHMT2	Unpublished data	PDB: 6DK3
COP9 signalosome	Lingaraju et al., 2014	PDB: 4D10
APC2-UBCH10 complex	Brown et al., 2015	PDB: 4YII
Crystal Structure of the SpRpn10 VWA domain	Riedinger et al., 2010	PDB: 2X5N
Structure of CfBRCC36-CfKIAA0157 complex	Zeqiraj et al., 2015	PDB: 5CW3
Experimental Models: Cell Lines
Spodoptera frugiperda Sf9 cells	Thermo Fisher Scientific	Cat# 11496015
Tni insect cells	Expression Systems	Cat# 94-002F
Human osteosarcoma (U2OS) cells	Dr. Durocher	N/A
U2OS Rap80-KO	Dr. Durocher	N/A
HEK293T	Dr. Peters	N/A
Recombinant DNA
pFastBac MmABRAXAS	This paper	N/A
pFastBac MmABRO1	This paper	N/A
pFastBac MmBRCC36	This paper	N/A
pFastBac MmBRE	This paper	N/A
pFastBac MmMERIT40	This paper	N/A
pFastBac MmRAP80	This paper	N/A
pFastBac MmRAP80 250-413	This paper	N/A
pFastBac HsABRO1	This paper	N/A
pFastBac HsBRCC36	This paper	N/A
pFastBac HsBRE	This paper	N/A
pFastBac HsMERIT40	This paper	N/A
pFastBac SHMT2	This paper	N/A
pFastBac Strep-BirA-HsABRO1	This paper	N/A
SHMT2α	SGC structural genomics consortium	3OU5
GFP-RAP80(WT)	Dr. A.M. Jetten	N/A
GFP-RAP80(ΔAIR) (Δ274-334)	This paper	N/A
pFasBac- mouse ABRO1 (1-260) - ABRAXAS (269-407)	This paper	N/A
Human BRCA1-BRCT	Wu et al., 2016	N/A
pFastBac- ABRAXAS-sortase site -FLAG tag at the C terminus (ABRAXAS 1-394 - LPETGDYKDHDGDYKDHDIDYKDDDDK)	This paper	N/A
Software and Algorithms
Fiji	Schindelin et al., 2012	https://fiji.sc
DYNAFIT	Kuzmič, 2009	http://www.biokin.com/dynafit/
Prism		https://www.graphpad.com
XDS	Kabsch, 2010	http://xds.mpimf-heidelberg.mpg.de
DIALS	Winter et al., 2018	https://dials.diamond.ac.uk
POINTLESS	Evans, 2011	http://www.ccp4.ac.uk
AIMLESS	Evans and Murshudov, 2013	http://www.ccp4.ac.uk
STARANISO	Global Phasing	http://staraniso.globalphasing.org
SHELXD	Sheldrick, 2008	http://shelx.uni-goettingen.de
PHASER	McCoy et al., 2007	https://www.phaser.cimr.cam.ac.uk/
PIRATE	Cowtan, 2000	http://www.ccp4.ac.uk
PARROT	Cowtan, 2010	http://www.ccp4.ac.uk
PHENIX	Adams et al., 2010	https://www.phenix-online.org
COOT	Emsley et al., 2010	https://www2.mrc-lmb.cam.ac.uk/personal/pemsley/coot/
ISOLDE	Croll, 2018	https://isolde.cimr.cam.ac.uk
REFMAC	Nicholls et al., 2012	http://www.ccp4.ac.uk
AUTOBUSTER	Global Phasing	https://www.globalphasing.com
CNS	Schröder et al., 2010	http://cns-online.org/v1.3/
ROSETTA	Wang et al., 2016	https://www.rosettacommons.org
PDB-REDO	Joosten et al., 2014	https://pdb-redo.eu
MOLPROBITY	Chen et al., 2010	http://molprobity.biochem.duke.edu
CryoFLARE	A.D.S., unpublished data	http://www.cryoflare.org
motioncor2	Li et al., 2013	https://msg.ucsf.edu/software
GCTF	Zhang, 2016	https://www.mrc-lmb.cam.ac.uk/kzhang/
Gautomatch		https://www.mrc-lmb.cam.ac.uk/kzhang/
RELION	Scheres, 2012	https://www3.mrc-lmb.cam.ac.uk/relion
EMAN2	Tang et al., 2007	https://blake.bcm.edu/emanwiki/
ResMap	Kucukelbir et al., 2014	http://resmap.sourceforge.net