Skip to main content
. 2021 Mar 4;10:e64563. doi: 10.7554/eLife.64563

Figure 5. The hinge region of HP1α is sufficient for DNA compaction and condensate formation.

(A) Cartoon of HP1α with color-coded disordered regions: positive residues (K and R) blue, negative residues (E and D) red, proline yellow, and all other residues gray. Key HP1α domains are labeled: chromodomain (CD), chromoshadow domain (CSD), hinge, N-terminal extension (NTE), and C-terminal extension (CTE). (B) Kymogram of DNA compaction by the hinge domain. DNA is labeled with dCas9 (top) and YOYO-1 (middle), also shown as composite image (bottom). Arrowhead represent estimated time of protein injection. (B-) or (-) specifies location of the barrier. (C) Average DNA compaction by 5 μM HP1α (N = 157) and 5 μM HP1α-hinge (N = 169), error bars represent standard deviations. (D and E) Bright-field images of the HP1α-hinge and DNA. (D) Titration of the HP1α-hinge with 500 nM 147 bp DNA. (E) Titration of 147 bp DNA with 12.5 μM HP1α-hinge. Purple boxes indicate presence of condensates.

Figure 5.

Figure 5—figure supplement 1. The hinge region of HP1 is sufficient for DNA compaction.

Figure 5—figure supplement 1.

(A) Cartoon of HP1α hinge with color-coded disordered residues: positive residues (K and R) blue, negative residues (E and D) red, proline yellow, and all other residues grey. The HP1α hinge contains three basic patches (BP). (B) Timestamped images of DNA labeled with YOYO-1 undergoing compaction by 5 μM HP1α hinge (unlabeled) shown before, during, and after compaction. (B-) specifies location of the barrier. (C) Average DNA compaction by the HP1α hinge (N = 169). Error bars represent standard deviations. Compaction velocity estimated from linear fit to data (cyan). Fit constrained to the region within the two red lines.