About TRAPPC / Trafficking Protein Particle Complex:
The TRAPP complex, or the Transport Protein Particle, is a protein that is essential in the transport of particles between organelles. There are two forms of this complex, TRAPP I and TRAPP II. TRAPP I is a multisubunit complex that consists of seven subunits (Bet5, Bet3, Trs20, Trs23, Trs31, Trs33, Trs85) while TRAPP II has three additional subunits (Trs65, Trs120, and Trs130).
The subunits named above have the name of TRAPP complex particles in yeast, but they are also genes in mammals. These are called TRAPPC1, TRAPPC2, TRAPPC2L, TRAPPC3, TRAPPC3L, TRAPPC4, TRAPPC5, TRAPPC6A, TRAPPC6B, TRAPPC8, TRAPPC9, TRAPPC10, TRAPPC11, TRAPPC13, and TRAPPC14.
TRAPP complexes are transported protein particles that play a role in endoplasmic reticulum-to-Golgi transport and also acts as a Ypt/Rab GTPase nucleotide exchanger, GEF. These are the functions that have been identified in yeast, but the role that the two TRAPP complexes present in humans play is less clear.
Trafficking Protein Particle Complex Mechanism
The mechanisms for the TRAPP Complex parties are still uncertain. Some mechanisms in yeast TRAPP complexes have been identified, but in mammals, it is through the TRAPP could act as a membrane tether.
Each TRAPP complex gene has its own interactions. For instance, Bet5, also known as the TRAPPC1 Gene, interacts with TRAPPC2, TRAPPC3, TRAPPC4, TRAPPC5, and TRAPPC9 genes. Trs20, also known as TRAPPC2, interacts with TRAPPC1, TRAPPC3, TRAPPC5, TRAPPC6A, and TRACC6B
Trafficking Protein Particle Complex Structure
Structurally, TRAPP subunits fall into two groups. The first group, which includes Trs20 and Trs23 has a longin-domain fold involved in protein-protein interactions. The second group, which includes Trs31 and Trs33, have similar structures.