Figure 6
From: LEDGINs inhibit late stage HIV-1 replication by modulating integrase multimerization in the virions
LEDGINs enhance multimerization of HIV integrase. (A) Direct and specific interaction of LEDGINs with HIV-1 Pol polyprotein. (A) Titration of CX05045 or raltegravir against a constant background of 33 nM His-MBP-sPol-PRD25N and 33 nM GST-sPol-PRD25N. DMSO (vehicle) included as no-inhibitor control. Only CX05045 was able to enhance the Pol-Pol multimerization with an EC50 of 8.7 nM (95% CI 5.7-13.4). Data represent mean values ± standard deviations of duplicate measurements in two independent experiments. (B, C) FRET analysis of IN multimerization in the virions. Histograms were plotted from pooled data of two independent experiments for (B) wild type HIV-1 (HIV-INWT) and (C) LEDGIN-resistant (HIV-INA128T) virions. (B) FRET ratios for populations of fluorescent HIV-INWT virions produced in the presence of DMSO (dark gray bar), CX05045 (light gray bar) or RAL (hatched bar) along with the respective normal distribution fits for DMSO (dark line), RAL (light gray line) and CX05045 (broken line) are shown. The calculated mean and 95% CI of the FRET ratios for HIV-INWT are 1.25 (95% CI 1.23-1.28) (DMSO), 1.22 (95% CI 1.19-1.25) (RAL) and 1.43 (95% CI 1.42-1.45) (CX05045). (C) FRET ratios for populations of fluorescent HIV-INA128T virions produced in the presence of DMSO (dark gray bar) or CX05045 (light gray bar) along with the respective normal distribution fits for DMSO (dark gray line) and for CX05045 (broken line) are shown. The calculated mean and 95% CI of the FRET ratios for HIV-INA128T when produced in the presence or absence of CX05045 are 1.23 (95% CI 1.21-1.25) and 1.26 (95% CI 1.24-1.27), respectively. A mean FRET ratio that equals unity means no FRET. *p <0.05; Student t test.