What is the Difference Between Toll-Like Receptors and Nod-Like Receptors?
🆚 Go to Comparative Table 🆚Toll-Like Receptors (TLRs) and Nod-Like Receptors (NLRs) are both innate immune sensors that play crucial roles in recognizing and responding to pathogen-associated molecular patterns (PAMPs). However, there are key differences between the two:
- Location: TLRs are transmembrane receptors, while NLRs are intracellular proteins.
- Ligands: TLRs mainly detect motifs or signatures from bacteria, viruses, protozoa, and fungi. In contrast, NLRs primarily detect intracellular bacteria. Both TLRs and NLRs contribute to the onset of adaptive immunity.
- Signaling: TLRs activate intracellular signaling cascades that induce the expression of a variety of overlapping and unique genes involved in the inflammatory and immune responses. NLRs, on the other hand, activate transcription via the NFkB pathway.
- Types of Receptors: In mammals, 13 genes encoding TLRs have been identified (TLR1-TLR10 in humans and TLR1-TLR13 in mice). NLRs, also known as Nod-like proteins, are a smaller family of receptors.
Both TLRs and NLRs are highly conserved through evolution and contain leucine-rich repeats. They can also cooperate with each other to regulate inflammatory and apoptotic responses.
Comparative Table: Toll-Like Receptors vs Nod-Like Receptors
Toll-Like Receptors (TLRs) and NOD-Like Receptors (NLRs) are both groups of receptors that belong to the Pattern Recognition Receptors (PRRs) family, which play crucial roles in innate immunity. Here is a table summarizing the differences between TLRs and NLRs:
| Feature | Toll-Like Receptors (TLRs) | NOD-Like Receptors (NLRs) |
|---|---|---|
| Description | TLRs are evolutionarily conserved receptors that detect pathogen-associated molecular patterns (PAMPs) and initiate downstream signaling pathways to induce genes involved in host defense. | NLRs are another group of receptors in the PRRs family that detect PAMPs and danger-associated molecular patterns (DAMPs). |
| Location | TLRs are mainly located on the cell membrane and in endolysosomal compartments. | NLRs are located in the cytoplasm of cells. |
| Structure | TLRs are type I integral transmembrane proteins, consisting of an N-terminal domain (NTD) located outside the membrane, a middle single helix transmembrane domain traversing the membrane, and a C-terminal domain (CTD) located towards the cytoplasm. | NLRs have a distinct structure, with a C-terminal leucine-rich repeat (LRR) domain and an N-terminal nucleotide-binding domain (NBD) that contains the NACHT domain. |
| Key Molecules Detected | TLRs detect various PAMPs, such as triacylated lipopeptides, hemagglutinins, glycosylphosphatidylinositol, phospholipoman, lipoarabinomannan, peptidoglycans, porins, and lipoproteins. | NLRs detect PAMPs and DAMPs, which are released from damaged host cells. |
Both TLRs and NLRs play essential roles in the innate immune response, but they detect different types of molecules and have distinct structures and locations within the cell.
- Ionotropic vs Metabotropic Receptors
- B Cell Receptor vs T Cell Receptor
- Gustatory Receptors vs Olfactory Receptors
- Internal Receptors vs Cell Surface Receptors
- Endocytosis vs Receptor Mediated Endocytosis
- NK Cells vs NKT Cells
- G Protein Coupled Receptors vs Receptor Tyrosine Kinases
- AMPA vs NMDA Receptors
- Tonic vs Phasic Receptors
- Nicotinic vs Muscarinic Receptors
- G Protein Linked Receptors vs Enzyme Linked Receptors
- H1 vs H2 Receptors
- Nociceptive vs Neuropathic Pain
- Pinocytosis vs Receptor Mediated Endocytosis
- D1 vs D2 Receptors
- Receptor vs Effector
- NRF1 vs NRF2
- Muscarinic vs Nicotinic Receptors
- Innate vs Adaptive Immunity