Material Data Sheet

Ubiquitin Mutant F4A

Price: $89.00
Catalog #: UM-F4A

Ubiquitin Mutant F4A

1 mg

Ubiquitin has two functional surfaces which are critical for various signaling processes. The hydrophobic patch (Leu8, Ile44 and Val70) is important for binding to the proteasome, UIM (ubiquitin interacting motif) and UBA (ubiquitin associated) domains. This multifunctional surface thus influences many ubiquitination and deubiquitination reactions. The other surface defined by Phe4 is required specifically for non-proteasome-dependent functions such as endocytosis and internalization, which often involves mono-ubiquitination. It is thought that Phe4 may be involved in specific protein-protein interactions that facilitate endocytosis. In addition, Ile44 forms a di-leucine signal with Leu43 that may be involved in mediating endocytosis of substrate proteins that are mono-ubiquitinated. Ubiquitin F4A can form an E1-catalyzed active thioester at the C-terminus allowing the molecule to be transferred to the lysines of substrate proteins.

Product Information

Soluble and stable in aqueous buffers up to 10 mg/ml.
8.5 kDa
> 95% by SDS-PAGE
This is a lyophilized powder

Use & Storage


Typical concentrations for non rate-limiting support of in vitro conjugationreactions range from 200 μM-1 mM depending on experimental conditions.


Store at -20°C after solubilization in desired buffer. Avoid multiple freeze/thaw cycles.



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