Ions, low-MW precursors of cellular macromolecules, products of intermediary metabolism, & small intracellular signaling molecules can pass from cell to cell through gap junctions.

TLS Online TPP Program

#Id: 8341

#XL - Q Biochemistry

Two major classes of actin-nucleating proteins:

1. Formins nucleate the assembly of unbranched filaments 

2. Arp2/3 complex nucleates the assembly of branched actin networks

TLS Online TPP Program

#Id: 8340

#XL - Q Biochemistry

Gelsolin, is regulated by Ca+2 ion concentration and sever actin filaments.

TLS Online TPP Program

#Id: 8339

#XL - Q Biochemistry

Filament capping proteins:

CapZ blocks (+)end Tropomodulin blocks (-)end

TLS Online TPP Program

#Id: 8338

#XL - Q Biochemistry

Profilin can bind proteins with sequences rich in proline residues at the same time it is bound to actin.

TLS Online TPP Program

#Id: 8337

#XL - Q Biochemistry

Profilin – G-actin nucleotide exchange (ADP to ATP) 

Cofilin – F-actin disassembly

Thymosin B-4 – G-actin monomer sequestering

TLS Online TPP Program

#Id: 8336

#XL - Q Biochemistry

Actin filament treadmilling is accelerated by:

Profilin and Cofilin