Three-dimensional analysis tool for segmenting and measuring the structure of telomeres in mammalian nuclei

摘要

Quantitative analysis in combination with fluorescence microscopy calls for innovative digital image measurementtools. We have developed a three-dimensional tool for segmenting and analyzing FISH stained telomeresin interphase nuclei. After deconvolution of the images, we segment the individual telomeres and measure adistribution parameter we call ρT . This parameter describes if the telomeres are distributed in a sphere-likevolume (ρT ≈ 1) or in a disk-like volume (ρT 1). Because of the statistical nature of this parameter, we haveto correct for the fact that we do not have an infinite number of telomeres to calculate this parameter. In thisstudy we show a way to do this correction. After sorting mouse lymphocytes and calculating ρT and using thecorrection introduced in this paper we show a significant difference between nuclei in G2 and nuclei in eitherG0/G1 or S phase. The mean values of ρT for G0/G1, S and G2 are 1.03, 1.02 and 13 respectively.