Visualization of repetitive DNA sequences in human chromosomes with transcription activator-like effectors

Proc Natl Acad Sci U S A. 2013 Dec 24;110(52):21048-53. doi: 10.1073/pnas.1319097110. Epub 2013 Dec 9.

Abstract

We describe a transcription activator-like effector (TALE)-based strategy, termed "TALEColor," for labeling specific repetitive DNA sequences in human chromosomes. We designed TALEs for the human telomeric repeat and fused them with any of numerous fluorescent proteins (FPs). Expression of these TALE-telomere-FP fusion proteins in human osteosarcoma's (U2OS) cells resulted in bright signals coincident with telomeres. We also designed TALEs for centromeric sequences unique to certain chromosomes, enabling us to localize specific human chromosomes in live cells. Meanwhile we generated TALE-FPs in vitro and used them as probes to detect telomeres in fixed cells. Using human cells with different average telomere lengths, we found that the TALEColor signals correlated positively with telomere length. In addition, suspension cells were followed by imaging flow cytometry to resolve cell populations with differing telomere lengths. These methods may have significant potential both for basic chromosome and genome research as well as in clinical applications.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Chromosomes, Human / genetics*
  • Flow Cytometry
  • Fluorescent Antibody Technique
  • Fluorescent Dyes / metabolism*
  • Humans
  • Plasmids / genetics
  • Repetitive Sequences, Nucleic Acid / genetics*
  • Staining and Labeling / methods
  • Telomere / genetics
  • Transcriptional Activation / genetics*

Substances

  • Fluorescent Dyes