Related Experiment Video
Updated: Jul 19, 2026

In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
The role of ubiquitin in neurotrophin receptor signalling and sorting
1Program in Cellular and Molecular Biosciences, Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849, USA. wootemw@auburn.edu
Abstract:
NGF (nerve growth factor) binding to TrkA (tropomyosin receptor kinase A) induces dimerization, autophosphorylation and internalization of the receptor to signalling vesicles for delivery of differentiation signals. TrkA interacts with p75 receptor through the p62-TRAF-6 (tumour-necrosis-factor-receptor-associated factor 6) complex bridging the two receptors. The atypical protein kinase C is activated and recruited to the receptor complex as well. TrkA is Lys63-polyubiquitinated on Lys485 by the E3 (ubiquitin ligase), TRAF-6, and E2 (ubiquitin-conjugating enzyme), UbcH7. Inhibition of polyubiquitination has been observed to interrupt signalling and internalization. Furthermore, an absence of p62 prevents endosomal localization and signalling. Altogether, these findings reveal Lys63-linked polyubiquitin chains and the shuttling protein p62 co-ordinately regulate TrkA internalization, trafficking and sorting.
Related Concept Videos
Receptor Downregulation in MVBs
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
Enzyme-linked Receptors
Neurotrophin (NT) receptors are a family of RTKs, including trkA, trkB, and trkC (tropomyosin-related kinase) receptors. TrkA is specific for nerve growth factor (NGF), neurotrophin-6, and neurotrophin-7. TrkB binds...
The Early Endosome: Endocytosis of Transferrin
Regulated Protein Degradation
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
The Proteasome
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
The Proteasome
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...

