TRADD Antibody (Rabbit mAb) [F18K8] Datasheet

Biological Description

Specificity	TRADD Antibody (Rabbit mAb) [F18K8] detects endogenous levels of total TRADD protein.
Background	Tumor necrosis factor receptor type 1–associated death domain protein (TRADD) is a death-domain–containing adaptor encoded by the TRADD gene that binds directly to the intracellular death domain of TNFR1 and acts as a central platform that couples TNF receptor engagement to distinct programs of NF‑κB activation, apoptosis, and necrotic cell death. The C‑terminal death domain of TRADD is sufficient for interaction with the TNFR1 death domain and for initiating both NF‑κB activation and programmed cell death, while the N‑terminal region provides binding interfaces for TRAF2 and other signaling components, allowing TRADD to assemble receptor-proximal complexes with defined composition and output. Upon trimeric TNFα binding to TNFR1, conformational change in the receptor permits recruitment of TRADD, which then nucleates formation of a membrane-associated “complex I” by binding TRAF2, cIAPs and RIP1; in this configuration, K63-linked ubiquitination of RIP1 and scaffold activity of TRAF2 support activation of the IKK complex and MAP kinases, leading to NF‑κB–dependent transcription of genes that promote inflammation, survival and, in many contexts, suppression of apoptotic signaling. TRADD simultaneously provides a bifurcation point for death signaling: its direct interaction with TRAF2 preferentially drives NF‑κB activation, whereas its direct interaction with FADD/MORT1 via homotypic death domain contacts seeds formation of a secondary cytosolic “complex II” containing FADD and caspase‑8 that can execute apoptosis when survival signals are compromised. Dominant-negative TRAF2 mutants that lack the N‑terminal RING finger inhibit TNF‑mediated NF‑κB activation without affecting apoptosis, while dominant-negative FADD mutants lacking the N‑terminal portion block TNF‑induced apoptosis but leave NF‑κB activation intact, demonstrating that the two TNFR1–TRADD signaling cascades diverge at TRADD into TRAF2‑dependent survival/inflammatory signaling and FADD‑dependent apoptotic signaling. TRADD also participates in TRIF-dependent Toll-like receptor pathways: TRADD-deficient mice show abrogated TNF-induced apoptosis, impaired recruitment of TRAF2 and RIP1 ubiquitination at TNFR1, markedly reduced but not fully abolished NF‑κB and MAPK activation downstream of TNFR1, and reduced TRIF-dependent cytokine production and NF‑κB/MAPK activation in fibroblasts in response to TLR3 and TLR4 agonists, indicating that TRADD is essential for TNFR1 signaling and exerts cell type–specific control in TLR-mediated inflammatory responses. Structural analysis of the TRADD death domain reveals a novel fold within the death-domain superfamily comprising an all‑helix Greek key motif plus a β‑hairpin flanked by helices that creates a highly charged surface conducive to electrostatic interactions with other death-domain proteins, providing a structural basis for homotypic DD pairing with TNFR1, FADD, RIP1 and p75 neurotrophin receptor and explaining how TRADD can mediate both receptor binding and assembly of multiple distinct signaling complexes. Functional dissection further shows that TRADD and RIP1 compete for recruitment to TNFR1; TRADD is required for TNFR1-induced NF‑κB activation and caspase‑8–dependent apoptosis but dispensable for TNFR1-initiated, RIP1-dependent necrosis, so the balance between TRADD and RIP1 association at the receptor determines whether TNF signaling favors survival/inflammation, apoptotic death or necrotic death programs. These mechanistic insights define TRADD as a structurally unique death-domain adaptor whose N‑ and C‑terminal regions orchestrate assembly of TRAF2-, RIP1- and FADD-containing complexes downstream of TNFR1 and TRIF, and whose recruitment and competition with RIP1 at the receptor-proximal level set the trajectory of TNF/TLR signaling toward NF‑κB activation, caspase‑8–mediated apoptosis or necrosis, making TRADD an informative target for probing and modulating death receptor and innate immune pathways in cancer, autoimmunity and inflammatory disease.

Specificity

TRADD Antibody (Rabbit mAb) [F18K8] detects endogenous levels of total TRADD protein.

Background

Tumor necrosis factor receptor type 1–associated death domain protein (TRADD) is a death-domain–containing adaptor encoded by the TRADD gene that binds directly to the intracellular death domain of TNFR1 and acts as a central platform that couples TNF receptor engagement to distinct programs of NF‑κB activation, apoptosis, and necrotic cell death. The C‑terminal death domain of TRADD is sufficient for interaction with the TNFR1 death domain and for initiating both NF‑κB activation and programmed cell death, while the N‑terminal region provides binding interfaces for TRAF2 and other signaling components, allowing TRADD to assemble receptor-proximal complexes with defined composition and output. Upon trimeric TNFα binding to TNFR1, conformational change in the receptor permits recruitment of TRADD, which then nucleates formation of a membrane-associated “complex I” by binding TRAF2, cIAPs and RIP1; in this configuration, K63-linked ubiquitination of RIP1 and scaffold activity of TRAF2 support activation of the IKK complex and MAP kinases, leading to NF‑κB–dependent transcription of genes that promote inflammation, survival and, in many contexts, suppression of apoptotic signaling. TRADD simultaneously provides a bifurcation point for death signaling: its direct interaction with TRAF2 preferentially drives NF‑κB activation, whereas its direct interaction with FADD/MORT1 via homotypic death domain contacts seeds formation of a secondary cytosolic “complex II” containing FADD and caspase‑8 that can execute apoptosis when survival signals are compromised. Dominant-negative TRAF2 mutants that lack the N‑terminal RING finger inhibit TNF‑mediated NF‑κB activation without affecting apoptosis, while dominant-negative FADD mutants lacking the N‑terminal portion block TNF‑induced apoptosis but leave NF‑κB activation intact, demonstrating that the two TNFR1–TRADD signaling cascades diverge at TRADD into TRAF2‑dependent survival/inflammatory signaling and FADD‑dependent apoptotic signaling. TRADD also participates in TRIF-dependent Toll-like receptor pathways: TRADD-deficient mice show abrogated TNF-induced apoptosis, impaired recruitment of TRAF2 and RIP1 ubiquitination at TNFR1, markedly reduced but not fully abolished NF‑κB and MAPK activation downstream of TNFR1, and reduced TRIF-dependent cytokine production and NF‑κB/MAPK activation in fibroblasts in response to TLR3 and TLR4 agonists, indicating that TRADD is essential for TNFR1 signaling and exerts cell type–specific control in TLR-mediated inflammatory responses. Structural analysis of the TRADD death domain reveals a novel fold within the death-domain superfamily comprising an all‑helix Greek key motif plus a β‑hairpin flanked by helices that creates a highly charged surface conducive to electrostatic interactions with other death-domain proteins, providing a structural basis for homotypic DD pairing with TNFR1, FADD, RIP1 and p75 neurotrophin receptor and explaining how TRADD can mediate both receptor binding and assembly of multiple distinct signaling complexes. Functional dissection further shows that TRADD and RIP1 compete for recruitment to TNFR1; TRADD is required for TNFR1-induced NF‑κB activation and caspase‑8–dependent apoptosis but dispensable for TNFR1-initiated, RIP1-dependent necrosis, so the balance between TRADD and RIP1 association at the receptor determines whether TNF signaling favors survival/inflammation, apoptotic death or necrotic death programs. These mechanistic insights define TRADD as a structurally unique death-domain adaptor whose N‑ and C‑terminal regions orchestrate assembly of TRAF2-, RIP1- and FADD-containing complexes downstream of TNFR1 and TRIF, and whose recruitment and competition with RIP1 at the receptor-proximal level set the trajectory of TNF/TLR signaling toward NF‑κB activation, caspase‑8–mediated apoptosis or necrosis, making TRADD an informative target for probing and modulating death receptor and innate immune pathways in cancer, autoimmunity and inflammatory disease.

Usage Information

Application

WB, IHC, IF, FCM

Dilution

WB	IHC	IF	FCM
1:500 - 1:1000	1:100 - 1:200	1:50 - 1:100	1:30

Reactivity

Human

Source

Rabbit Monoclonal Antibody

MW

34 kDa

Storage Buffer

PBS, pH 7.2+50% Glycerol+0.05% BSA+0.01% NaN3

Storage
(from the date of receipt)

-20°C (avoid freeze-thaw cycles), 2 years

References

https://pubmed.ncbi.nlm.nih.gov/7758105/
https://pubmed.ncbi.nlm.nih.gov/8565075/

TRADD Antibody (Rabbit mAb) [F18K8]

Biological Description

Usage Information

References

Application Data