Arp

2022-08-25: reference:

Arp2-3 (Actin-related protein 2/3) #

• Mediates branched nucleation of actin filaments; pretty crucial for Axon Guidance:

  • VCA = C-terminus catalytic domain. C = connector, A = accidic, V = WASP homology… something like that.
  • 
  • The Arp2/3 Complex Is Essential for Distinct Stages of Spine Synapse Maturation, Including Synapse Unsilencing
    • Although the Arp2/3 complex is not required for key spine maturation steps, such as presynaptic contact and recruitment of MAGUK (membrane-associated guanylate kinase) scaffolding proteins or NMDA receptors, it is necessary for the recruitment of AMPA receptors - synapse unsilencing.
    • This Actin branching in neurite development looks like what can be described as lateral growth.

• New insights into the regulation and cellular functions of the ARP2/3 complex

  • NPFs (nucleation/branching promotion facotrs) includes WASP/N-WASP, WAVE aka SCAR, JMY. “Type II” includes Cortactin and HS1. This paper goes deeper into how they bind to the VCA and stuff.
  • NPFs are regulated by PIP, GTPases, and some kinases.
  • Branching (Arp2/3 inhibitors) include Cofilin, GMFs, Gadkin, PICK1
  • Since it regulates actin, it’s really important for so many ceullar functions. Actin mediates endolysosomal fission and endocytosis, adhering junctions, and of course axon guidance.