Activity: Verified in K63-linked Di-ubiquitin Hydrolysis Assay.
Verified Applications: Recombinant human AMSH* is a Ubiquitin-specific deconjugating fusion-enzyme that is highly specific for K63-linked poly-ubiquitin. Appropriate enzyme concentrations are specific to the application.
2 μg UBA1 run on 4-12% SDS-PAGE gel under reducing conditions, then visualized with Colloidal Coomassie Blue Stain.
Formulation: 40 mM HEPES, 100 mM NaCl, 10% Glycerol, 1 mM EDTA, 1 mM TCEP, pH 7.6
Shipping: The product is shipped with dry ice or equivalent. Upon receipt, store it immediately at the temperature recommended below.
Storage and Stability: Use a manual defrost freezer and avoid repeated freeze-thaw cycles. Aliquot and store ≤ -70°C (stable for 24 months from date of receipt).
Protein Sequence: GPGSTANPFEQDVEKATNEYNTTEDWSLIMDICDRVGSTPSGAKDCLKAIMKRVNHKVPHVALQALTLLGACVANCGKIFHLEVCSRDFATEVRSVIKNKAHPKVCEKLKSLMVEWSEEFQKDPQFSLISATIKSMKEEGVTFPSAGSQTVAAAAKNGTSLNKNKEDEDIAKAIELSLQEQKQQYTETGGSSGGSNSESIPTIDGLRHVVVPGRLCPQFLQLASANTARGVETCGILCGKLMRNEFTITHVLIPKQSAGSDYCNTENEEELFLIQDQQGLITLGWIHTHPTQTAFLSSVDLHTHCSYQMMLPESVAIVCSPKFQETGFFKLTDHGLEEISSCRQKGFHPHSKDPPLFCSCSHVTVVDRAVTITDLR
Background Information and Alternate Names
Species & domain architecture
Human AMSH (also known as STAMBP) (424 aa, ~46 kDa) houses a Zn²⁺-dependent JAMM/MPN⁺ catalytic core whose ordered Ins-2 loop enforces Lys63-linked chain specificity. AMSH is only active when allosterically activated by its binding partners STAM1 or STAM2.
UPS pathway role
Binding the SH3 domain of STAM within ESCRT-0 recruits AMSH to early endosomes. There it trims Lys63 ubiquitin signals just before multivesicular-body scission, thereby modulating EGFR turnover and other ESCRT-regulated trafficking events.
Relevance to TPD & disease biology
Loss-of-function mutations in AMSH cause autosomal-recessive microcephaly–capillary malformation syndrome, whereas pharmacologic or genetic inhibition of STAMBP dampens NLRP7/NALP7 inflammasome activation and IL-1β release, highlighting its therapeutic potential in neurodevelopmental disorders, inflammation, and degrader off-target profiling.
References
McCullough J et al. Curr Biol 16, 160-165 (2006). PMID 16431367
Sato Y et al. Nature 455, 358-362 (2008). PMID 18758443
