Journal: The Journal of biological chemistry
Article Title: The C-terminal domains of ADAMTS1 contain exosites involved in its proteoglycanase activity.
doi: 10.1016/j.jbc.2023.103048
Figure Lengend Snippet: Figure 2. Inhibition of ADAMTS1 by TIMPs. A, inhibition of versicanase activity by TIMP family members. TIMP1, TIMP2, TIMP3, and TIMP4 (each at 500 nM) were incubated with ADAMTS1 (100 nM) for 1 h at 37 C before addition of V1-5GAG and digestion for 2 h. Following SDS-PAGE under reducing conditions (5% β-mercaptoethanol) and immunoblotting, FL V1-5GAG and versikine (VSK) were detected by the anti-Vc antibody. A representative immunoblot is shown (n = 2 independent experiments). B, inhibition of peptidolytic activity. TIMPs (each 25 nM) were incubated with a nominal con- centration of 25 nM ADAMTS1 for 1 h at 37 C before addition of the QF peptide substrate fluorescein-5(6)-carbonyl-Ala-Glu-Leu-Asn-Gly-Arg-Pro-Ile-Ser-Ile- Ala-Lys (5(6)-TAMRA) (3.5 μM) and digestion for 2 h. Following subtraction of the background (reactions not containing ADAMTS1), values were converted into percentage of ADAMTS1 activity in the absence of TIMPs and reported as average ± SD (n = 3, each point representing a technical replicate), p < 0.05 by Mann-Whitney test. C, titration of ADAMTS1 with TIMP3. TIMP3 (0–16 nM) was incubated with ADAMTS1 (20 nM nominal concentration) at 37 C for 1 h, and residual activity against the QF peptide FAM-AELNGRPISIAK-Tamra (3.5 μM) was determined. A representative titration curve is shown, each point representing a mean of two technical replicates. Final concentration of ADAMTS1 following titration was 10 nM. FL, full-length; No E, no enzyme; No I, no inhibitor; QF, Quenched-Fluorescent; TIMP, tissue inhibitor of metalloproteinase.
Article Snippet: Semiquantitative proteoglycan cleavage assays Purified V1-5GAG (100 nM) was digested with ADAMTS1, in TNC-B buffer at 37 C for 2 h. Where indicated, 500 μM recombinant human TIMP1, TIMP2, TIMP3, or TIMP4 (R&D Systems, Cat. n.: 970-TM, 971-TM, 973-TM, 974-TSF) were preincubated with 100 nM ADAMTS1 for 1 h at 37 C before digestion.
Techniques: Inhibition, Activity Assay, Incubation, SDS Page, Western Blot, MANN-WHITNEY, Titration, Concentration Assay