Related Experiment Video
Updated: Jun 23, 2026

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development
Published on: June 15, 2017
An amphioxus TLR with dynamic embryonic expression pattern responses to pathogens and activates NF-kappaB pathway via
Shaochun Yuan1, Shengfeng Huang, Wei Zhang
1State Key Laboratory of Biocontrol, Department of Biochemistry, College of Life Sciences, Sun Yat-sen (Zhongshan) University, 135 Xingangxi Rd, Guangzhou 510275, People's Republic of China.
Abstract:
A big bang expansion of the Vertebrate-type (V-type) TLRs was reported in amphioxus. To shed lights on its implications, a unique TLR which is reversely inserted into an intron of amphioxus PSMB7-10 by retrotransposition in the highly polymorphic proto-MHC region was cloned from Chinese amphioxus (Branchiostoma belcheri tsingtauense) and named as bbtTLR1. In situ assays showed that bbtTLR1 was predominantly expressed in pharynx and gut from larva to adult stages, which are considered as the first frontlines of amphioxus defense system. Acute immune challenges revealed that the expression of bbtTLR1 was stimulated by bacteria and their cell wall components, while suppressed by Glucan and Poly I:C in the digestive system. Amphioxus also had dozens of TIR adaptors from which we cloned bbtMyD88. BbtMyD88 expressed in 293T cells led to the activation of NF-kappaB pathway through its DEATH and middle domains. Moreover, this activation could be enhanced by bbtTLR1 through the direct association with bbtMyD88. In summary, this study provides evidence for the immune-relation of amphioxus V-type TLRs, and suggests that amphioxus TLR1 and MyD88 represent a basic evolutionary pathway.
More Related Videos
Related Concept Videos
NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
NF-kB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
Hedgehog Signaling Pathway
Amebiasis
Role Of Notch Signalling In Intestinal Stem Cell Renewal
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...
The Extrinsic Apoptotic Pathway

