Display Settings:

Items per page
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information

Results: 7

1.
Fig. 1

Fig. 1. From: A Second-Site Suppressor Significantly Improves the Defective Phenotype Imposed by Mutation of an Aromatic Residue in the N-terminal Domain of the HIV-1 Capsid Protein.

Ribbon diagram highlighting helices I, II, III, and VII in the N-terminal domain of HIV-1 CA. The ribbon diagram shows a top view of helices I, II, III, and VII in the N-terminal domain structure. The positions of two conserved hydrophobic residues Trp23 (helix I) and Phe40 (helix II) are shown. The positions of Val26 (helix I), Val59 (helix III), as well as I134 and I135 (helix VII) are also illustrated in the figure.

Shixing Tang, et al. Virology. ;359(1):105-115.
2.
Fig. 6

Fig. 6. From: A Second-Site Suppressor Significantly Improves the Defective Phenotype Imposed by Mutation of an Aromatic Residue in the N-terminal Domain of the HIV-1 Capsid Protein.

Phenotypes of single or double CA mutants. (A) The replication kinetics of WT and the following CA mutants in MT-4 cells are shown: WT (closed circles), V26I (open squares), R154K (open triangles), W23F/R154K (open circles) and V26I/R154K (open diamonds). (B) Virus infectivity was plotted as the percentage of WT infectivity, which was set at 100%. Note that the data of Fig. 5A and 6A were obtained from the same experiment; thus, the WT curves in both figures are identical.

Shixing Tang, et al. Virology. ;359(1):105-115.
3.
Fig. 3

Fig. 3. From: A Second-Site Suppressor Significantly Improves the Defective Phenotype Imposed by Mutation of an Aromatic Residue in the N-terminal Domain of the HIV-1 Capsid Protein.

Transmission electron microscopy of WT and mutant virions produced in HeLa and MT-4 cells. HeLa cells: (A) HIV-1 WT; (B) W23F. MT-4 cells: (C) WT; (D) W23F/V26I; (E) W23F/V26I/R154K. The arrows point to representative particles in the field with a WT phenotype (i.e., having conical cones). The scale bars are 100 nm (A, B, and C) or 200 nm (D and E).

Shixing Tang, et al. Virology. ;359(1):105-115.
4.
Fig. 4

Fig. 4. From: A Second-Site Suppressor Significantly Improves the Defective Phenotype Imposed by Mutation of an Aromatic Residue in the N-terminal Domain of the HIV-1 Capsid Protein.

Dominant negative activity of W23A and W23F. HeLa cells were transfected with 5 μg of the following plasmid DNAs: WT alone, W23A or W23F alone, and 5:1, 1:1, and 1:5 mixtures of WT and either W23A or W23F. Virus stocks were harvested, normalized for RT activity, and used to infect LuSIV cells (Roos et al., 2000). The values in the bar graph represent infectivity as the percentage of the WT value, which was set at 100%. Here as well as in Figs. 5 and 6, error bars indicate the standard deviation from at least three independent experiments.

Shixing Tang, et al. Virology. ;359(1):105-115.
5.
Fig. 7

Fig. 7. From: A Second-Site Suppressor Significantly Improves the Defective Phenotype Imposed by Mutation of an Aromatic Residue in the N-terminal Domain of the HIV-1 Capsid Protein.

Structural models of WT CA and the W23F/V26I mutant illustrating contacts between the side chains of Trp23 and Val26 or the substituted Phe23 and Ile26 residues. (A) WT. Model number 10 in the 1GWP.pdb structure file of the N-terminal CA domain (Tang, Ndassa, and Summers, 2002) demonstrates the closest approach of the Trp23 (blue) and Val26 (magenta) side chains. Note that for clarity, the terminal methyl group of Met39 (yellow), which “hangs” over Trp23 is not shown. (B) W23F/V26I mutant. A possible model for the double mutant was constructed by mutating the Trp23 and Val26 residues and then slightly moving the Ile26 and Met39 side chains. Phe23 is shown in blue and Ile26 in magenta. This figure was kindly provided by Stewart R. Durell (NCI, NIH).

Shixing Tang, et al. Virology. ;359(1):105-115.
6.
Fig. 5

Fig. 5. From: A Second-Site Suppressor Significantly Improves the Defective Phenotype Imposed by Mutation of an Aromatic Residue in the N-terminal Domain of the HIV-1 Capsid Protein.

Phenotypes of second-site suppressor mutants. (A) WT proviral DNA and proviral DNAs bearing the indicated double or triple mutations were used to transfect MT-4 cells in a long-term culture experiment. RT activity in the culture supernatants was assayed to monitor the replication of WT (closed circles), W23F/V26I (open squares), and W23F/V26I/R154K (open triangles). A mock-infected control (no DNA) was also included (open circles). (B) Virus particles obtained from the supernatant fluids of transfected HeLa cells (black bars) and MT-4 cells (gray bars) were normalized and were used to infect LuSIV cells (Roos et al., 2000). The results are reported as percentage of WT infectivity, which was set at 100%. (C) and (D) Assays for detection of HIV-1 CA and RT retention in viral cores were performed as described previously (Tang et al., 2003b). The amounts of CA in the detergent-resistant core fractions were quantified and plotted as the percentage of total CA protein recovered from the sucrose step gradient (C). RT activity in the core fractions isolated from 20% to 70% (wt/wt) linear sucrose density gradients was quantified and plotted as the percentage of total RT activity (D). The values for WT and W23F in panels (C) and (D) were calculated from data in Fig. 2.

Shixing Tang, et al. Virology. ;359(1):105-115.
7.
Fig. 2

Fig. 2. From: A Second-Site Suppressor Significantly Improves the Defective Phenotype Imposed by Mutation of an Aromatic Residue in the N-terminal Domain of the HIV-1 Capsid Protein.

W23F phenotype. (A) Replication kinetics. MT-4 cells were transfected with WT and W23F plasmid DNAs. Cells were split 1:3 every 2 or 3 days. Virus production was monitored by assaying RT activity in the culture supernatants for each time point. Symbols: WT, open squares; W23F, open triangles; mock, open circles. (B) Incorporation of CypA into mature virus particles. HeLa cells were transfected with WT and W23F plasmid DNAs. Virion-associated proteins as well as CypA were detected by Western blot analysis, using anti-HIV RT and IN (Klutch et al., 1998) as well as anti-CA and anti-CypA (Tang et al., 2003b). The positions of individual viral proteins and CypA are indicated to the left of the gel. (C) Retention of HIV-1 RT in WT and W23F viral cores. Virions isolated from the supernatant fluids of transfected HeLa cells were treated with 0.3% NP-40 and were sedimented through 20% to 70% (wt/wt) linear sucrose gradients at 4°C for 16 h at 120,000 × g in a Beckman SW55Ti rotor (Tang et al., 2003b). Twelve fractions were collected from the top of the gradient. The bar graph shows RT activity in the fractions collected from WT (solid bars) or W23F (open bars) samples. (D) Retention of HIV-1 CA protein in viral cores. Detergent-treated virions were sedimented through sucrose step gradients centrifuged at 4°C for 60 min at 120,000 × g in a Beckman SW55Ti rotor (Tang et al., 2003b). Five fractions were collected from top of the gradients and were analyzed by Western blot using AIDS patient sera. HIV-1 CA protein bands are shown. Fractions 1 and 2 represent the soluble and detergent-soluble fractions, respectively. Fractions 3, 4, and 5 represent the detergent-resistant core fractions. The smaller band seen in W23F fractions 3 to 5 appears to be a CA degradation product.

Shixing Tang, et al. Virology. ;359(1):105-115.

Display Settings:

Items per page

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...
Write to the Help Desk