5vqf

Publication Abstract from PubMed

Transforming growth factor (TGF)-beta is synthesized as a proprotein that dimerizes in the endoplasmic reticulum. After processing in the Golgi to cleave the N-terminal prodomain from the C-terminal growth factor (GF) domain in each monomer, pro-TGF-beta is secreted and stored in latent complexes. It is unclear which prodomain and GF monomer are linked prior to proprotein convertase (PC) cleavage, and how much conformational change occurs following cleavage. We have determined a structure of pro-TGF-beta1 with the PC cleavage site mutated, to mimic the structure of the TGF-beta1 proprotein. Structure, mutation, and model building demonstrate that the prodomain arm domain in one monomer is linked to the GF that interacts with the arm domain in the other monomer in the dimeric structure, i.e., the prodomain arm domain and GF domain in each monomer are swapped. Swapping has important implications for the mechanism of biosynthesis in the TGF-beta family and is relevant to the mechanism for preferential formation of heterodimers over homodimers for some members of the TGF-beta family. Our structure, together with two previous ones, also provides insights into which regions of the prodomain-GF complex are highly structurally conserved, and which are perturbed by crystal lattice contacts.

Prodomain-Growth Factor Swapping in the Structure of pro-TGF-beta1.,Zhao B, Xu S, Dong X, Lu C, Springer TA J Biol Chem. 2017 Nov 5. pii: jbc.M117.809657. doi: 10.1074/jbc.M117.809657. PMID:29109152^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.