Table 1.

Statistical evaluation of the effect of microinjected substances on the distribution of chromatin in the nuclei of SW 13 [vimentin⁻] cells

Substance injected	No. of cells analyzed	No. of cells with abnormal chromatin	Percent of cells with abnormal chromatin
MOPS buffer (10 mM, pH 7)	13	1	8
HIV-1 PR	10	0	0
Peptides derived from wild-type or deletion mutant vimentin proteins:
NT1 peptide (residues 1–96)	18	16	89
1–51 peptide	12	12	100
1–60 peptide	10	10	100
1–92 peptide	11	10	91
423–465 peptide	10	0	0
17–51 peptide	11	1	9
17–60 peptide	12	12	100
17–92 peptide	11	10	91
32–51 peptide	11	2	18
32–60 peptide	12	0	0
32–92 peptide	12	11	92
1-Δ(25–38)-51 peptide	14	5	36
1-Δ(25–38)-60 peptide	17	16	94
1-Δ(25–38)-92 peptide	13	2	15
1-Δ(25–63)-92 peptide	16	0	0
1-Δ(25–68)-92 peptide	13	11	85
1-Δ(44–68)-92 peptide	14	12	86
Synthetic peptides identical to vimentin residues (as indicated in parentheses)
R23R (22–44)	12	9	75
R25R (44–68)	16	9	56
P410 (3–22)	25	7	28
P411 (24–44)	25	19	76
P412 (83–103)	28	23	82

For these experiments, the HIV-1 PR (0.01 mg/ml) and the vimentin peptides (0.2 mM) were dissolved in 10mM MOPS, pH 7 buffer. In a control experiment, all SW 13 T3M [vimentin⁺] cells injected with HIV-1 PR (13 of 13) exhibited nuclear aberrations. Cells were fixed 30 min after microinjection and stained with propidium iodide as described in MATERIALS AND METHODS. The indicated number of cells were evaluated by CLS microscopy. A single optical section, from the equatorial plane of the cell nucleus and characteristic of the entire series of sections, is presented for each substance injected in Figure 6.