Task: Text Categorization
Input (English): Most proteins, such as Gelsolin, interact with this by binding in the hydrophobic cleft between its subdomains 1 and 3. That cleft can also bind subdomain 2 of a different molecule of this protein, a nucleation reaction mediated by the Arp 2/3 complex. Although it can be visualized with fluorescently tagged phalloidin, that treatment increases the amount of this protein at the cell membrane, where its normal functions include promoting cell adhesion by linking to cadherin via vinculin and catenins. Thymosin beta 4 maintains the cellular concentration of its free form, while profilin catalyzes its exchange of ADP for ATP and thus promotes its polymerization. Once polymerized, it can form dynamic structures such as lamellipodia and the contractile ring during cytokinesis. ATP hydrolysis causes globular monomers to be released from its filamentous form., and troponin regulates its binding of motor proteins in sarcomeres. For 10 points, name this cytoskeletal protein that forms microfilaments and is associated with myosin in muscle cells.
Output (English): Science