NEM-Myosin II
(Actin Binding Protein)
NEM-Myosin II is a chemically inactivated myosin II preparation that preserves high-affinity F-actin binding while ATP-driven motor activity is suppressed. This makes it a tethering reagent to immobilize actin filaments on functionalized surfaces for surface-based fluorescence assays, in particular TIRF microscopy.
Immobilized filaments enable quantitative single-filament readouts (elongation, severing, branching, and regulatory protein effects) without confounding actin gliding caused by active motors. NEM-Myosin II is also suitable for biochemical actin-binding formats where a stable actin–myosin attachment is required (e.g., capture/retention, competition, and wash-stringent workflows).
| Protein | NEM-Myosin II |
| Origin | Skeletal muscle, rabbit (m. psoas) |
| Molecular mass | ~480 kDa |
| Protein description | NEM-Myosin II is a chemically inactivated fast skeletal muscle myosin II. Native myosin II is a hexameric actin-binding ATPase (two heavy chains plus two essential and two regulatory light chains) with a head–tail architecture. Chemical modification with N-ethylmaleimide (NEM), a thiol-reactive reagent, inactivates the ATP motor domains while preserving actin binding. This yields a non-motile actin-binding species that is well-suited for robust surface tethering of actin filaments. |
| Actin interaction | High-affinity binding to F-actin is preserved despite motor inactivation. |
| Form | Lyophilized, ready-to-use. |
| Quantity per unit | 2 × 100 µg |
| Buffer | 500 mM KCl, 20 mM Imidazole pH 7.0, 2 mM DTT, 10% disaccharides (upon reconstitution with 100 µl ultrapure water per vial to obtain 1 mg/ml). |
| Purity | As specified in the product datasheet. |
| Purification notes | Purified from rabbit skeletal muscle (m. psoas). |
| Protein concentration | Determined at OD280 (0.1% = 0.53). |
| Storage instructions | Store the freeze-dried product at -70°C. Once dissolved, keep on ice during use. For prolonged storage of reconstituted material, prepare a glycerol stock (50% final glycerol) and store at -20°C. Avoid repeated freeze/thaw cycles; clarify briefly to remove aggregates prior to imaging-sensitive assays if needed. |
| Shipping conditions | At ambient temperature. Upon delivery store at -70°C. |
| Remarks | For research use only. Not for use in human or veterinary diagnostic or therapeutic applications. |
| CAS no. | |
Proteins and buffers from Hypermol® are made of the ultrapure reagents in Milli-Q™ water, as described in our publications.
TAGLN2 polymerizes G-actin in a low ionic state but blocks Arp2/3-nucleated actin branching in physiological conditions.
Kim HR, Kwon MS, Lee S, Mun Y, Lee KS, Kim CH, Na BR, Kim BNR, Piragyte I, Lee HS, Jun Y, Jin MS, Hyun YM, Jung HS, Mun JY, Jun CD.
Sci Rep. 2018 Apr 3;8(1):5503. doi: 10.1038/s41598-018-23816-2.
