RT Journal Article
SR Electronic
T1 New Structural Insights into the Function of the Catalytically Active Human Taspase1
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.11.26.400622
DO 10.1101/2020.11.26.400622
A1 Nirupa Nagaratnam
A1 Silvia L. Delker
A1 Rebecca Jernigan
A1 Thomas E. Edwards
A1 Janey Snider
A1 Darren Thifault
A1 Dewight Williams
A1 Brent L. Nannenga
A1 Mary Stofega
A1 Lidia Sambucetti
A1 James J. Hsieh
A1 Andrew J. Flint
A1 Petra Fromme
A1 Jose M. Martin-Garcia
YR 2020
UL http://biorxiv.org/content/early/2020/11/27/2020.11.26.400622.abstract
AB Proteases can play essential roles in severe human pathology, ranging from degenerative and inflammatory illnesses to infectious diseases, with some, such as Taspase1, involved in growth and progression of tumors at primary and metastatic sites. Taspase1 is a N-terminal nucleophile (Ntn)-hydrolase overexpressed in primary human cancers, coordinating cancer cell proliferation, invasion, and metastasis. Loss of Taspase1 activity disrupts proliferation of human cancer cells in vitro and in mouse xenograft models of glioblastoma, thus this protein has the potential to become a novel anticancer drug target. It belongs to the family of Ntn-hydrolases, a unique family of proteins synthesized as enzymatically inactive proenzymes that become activated upon cleavage of the peptide bond on the N-terminal side of a threonine residue, which then becomes the catalytic site nucleophile. The activation process simultaneously changes the conformation of a long domain at the C-terminus of the alpha-subunit for which no full-length structural information exists and its function is poorly understood. Here we present a novel cloning strategy to generate a fully active, circularly permuted form of Taspase1 to determine the crystallographic structure of catalytically active human Taspase1 to 3.04Å. We discovered that this region forms a long helical domain and is indispensable for the catalytic activity of Taspase1. Together, our study highlights the importance of this element for the enzymatic activity of Ntn-hydrolases and suggests that this long domain could be a novel target for the design of inhibitors with the potential to be developed into anticancer therapeutics.Competing Interest StatementThe authors have declared no competing interest.