Limits...
The three-dimensional organization of telomeres in the nucleus of mammalian cells.

Chuang TC, Moshir S, Garini Y, Chuang AY, Young IT, Vermolen B, van den Doel R, Mougey V, Perrin M, Braun M, Kerr PD, Fest T, Boukamp P, Mai S - BMC Biol. (2004)

Bottom Line: In tumor cells, the 3D telomere organization is distorted and aggregates are formed.The results emphasize a non-random and dynamic 3D nuclear telomeric organization and its importance to genomic stability.Based on our findings, it appears possible to examine telomeric aggregates suggestive of genomic instability in individual interphase nuclei and tissues without the need to examine metaphases.

View Article: PubMed Central - HTML - PubMed

Affiliation: Manitoba Institute of Cell Biology, CancerCare Manitoba, University of Manitoba, 675 McDermot Avenue, Winnipeg, MB, R3E 0V9, Canada. tcychuang@hotmail.com

ABSTRACT

Background: The observation of multiple genetic markers in situ by optical microscopy and their relevance to the study of three-dimensional (3D) chromosomal organization in the nucleus have been greatly developed in the last decade. These methods are important in cancer research because cancer is characterized by multiple alterations that affect the modulation of gene expression and the stability of the genome. It is, therefore, essential to analyze the 3D genome organization of the interphase nucleus in both normal and cancer cells.

Results: We describe a novel approach to study the distribution of all telomeres inside the nucleus of mammalian cells throughout the cell cycle. It is based on 3D telomere fluorescence in situ hybridization followed by quantitative analysis that determines the telomeres' distribution in the nucleus throughout the cell cycle. This method enables us to determine, for the first time, that telomere organization is cell-cycle dependent, with assembly of telomeres into a telomeric disk in the G2 phase. In tumor cells, the 3D telomere organization is distorted and aggregates are formed.

Conclusions: The results emphasize a non-random and dynamic 3D nuclear telomeric organization and its importance to genomic stability. Based on our findings, it appears possible to examine telomeric aggregates suggestive of genomic instability in individual interphase nuclei and tissues without the need to examine metaphases. Such new avenues of monitoring genomic instability could potentially impact on cancer biology, genetics, diagnostic innovations and surveillance of treatment response in medicine.

Show MeSH

Related in: MedlinePlus

The distribution of telomeres in the nucleus of three typical cells selected from the G0/G1 phase (upper row), S phase (middle row) and G2/M phase (lower row). Each telomere distribution is shown from a top view (the XY plane), along the optical axis Z (left column), from a side view (XZ plane) as observed along the Y axis (centre column) and as a 3D image of the telomeres in an open nucleus (right column). When shown from the top and side views, the telomeres are displayed on top of the projected image of the nucleus. This projection demonstrates the extent of the chromatin (and therefore chromosomes) and defines the volume and borderline of the nucleus.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC425602&req=5

Figure 5: The distribution of telomeres in the nucleus of three typical cells selected from the G0/G1 phase (upper row), S phase (middle row) and G2/M phase (lower row). Each telomere distribution is shown from a top view (the XY plane), along the optical axis Z (left column), from a side view (XZ plane) as observed along the Y axis (centre column) and as a 3D image of the telomeres in an open nucleus (right column). When shown from the top and side views, the telomeres are displayed on top of the projected image of the nucleus. This projection demonstrates the extent of the chromatin (and therefore chromosomes) and defines the volume and borderline of the nucleus.

Mentions: Typical lymphocytes from different phases are shown in Fig. 5. The a/c ratio of these cells in the G0/G1, S and G2/M phases is 0.8, 0.8 and 6, respectively, and clearly shows the correlation of the a/c ratio with the telomere distribution and the organization of the telomeric disk that we found in the G2 phase. The elongation of the telomeres along the Z axis (the optical axis) relative to the XY plane has the same ratio as the point spread function of our system and results from the poorer optical resolution along the optical axis. However, this has a very small effect on the shape of the whole nucleus.


The three-dimensional organization of telomeres in the nucleus of mammalian cells.

Chuang TC, Moshir S, Garini Y, Chuang AY, Young IT, Vermolen B, van den Doel R, Mougey V, Perrin M, Braun M, Kerr PD, Fest T, Boukamp P, Mai S - BMC Biol. (2004)

The distribution of telomeres in the nucleus of three typical cells selected from the G0/G1 phase (upper row), S phase (middle row) and G2/M phase (lower row). Each telomere distribution is shown from a top view (the XY plane), along the optical axis Z (left column), from a side view (XZ plane) as observed along the Y axis (centre column) and as a 3D image of the telomeres in an open nucleus (right column). When shown from the top and side views, the telomeres are displayed on top of the projected image of the nucleus. This projection demonstrates the extent of the chromatin (and therefore chromosomes) and defines the volume and borderline of the nucleus.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC425602&req=5

Figure 5: The distribution of telomeres in the nucleus of three typical cells selected from the G0/G1 phase (upper row), S phase (middle row) and G2/M phase (lower row). Each telomere distribution is shown from a top view (the XY plane), along the optical axis Z (left column), from a side view (XZ plane) as observed along the Y axis (centre column) and as a 3D image of the telomeres in an open nucleus (right column). When shown from the top and side views, the telomeres are displayed on top of the projected image of the nucleus. This projection demonstrates the extent of the chromatin (and therefore chromosomes) and defines the volume and borderline of the nucleus.
Mentions: Typical lymphocytes from different phases are shown in Fig. 5. The a/c ratio of these cells in the G0/G1, S and G2/M phases is 0.8, 0.8 and 6, respectively, and clearly shows the correlation of the a/c ratio with the telomere distribution and the organization of the telomeric disk that we found in the G2 phase. The elongation of the telomeres along the Z axis (the optical axis) relative to the XY plane has the same ratio as the point spread function of our system and results from the poorer optical resolution along the optical axis. However, this has a very small effect on the shape of the whole nucleus.

Bottom Line: In tumor cells, the 3D telomere organization is distorted and aggregates are formed.The results emphasize a non-random and dynamic 3D nuclear telomeric organization and its importance to genomic stability.Based on our findings, it appears possible to examine telomeric aggregates suggestive of genomic instability in individual interphase nuclei and tissues without the need to examine metaphases.

View Article: PubMed Central - HTML - PubMed

Affiliation: Manitoba Institute of Cell Biology, CancerCare Manitoba, University of Manitoba, 675 McDermot Avenue, Winnipeg, MB, R3E 0V9, Canada. tcychuang@hotmail.com

ABSTRACT

Background: The observation of multiple genetic markers in situ by optical microscopy and their relevance to the study of three-dimensional (3D) chromosomal organization in the nucleus have been greatly developed in the last decade. These methods are important in cancer research because cancer is characterized by multiple alterations that affect the modulation of gene expression and the stability of the genome. It is, therefore, essential to analyze the 3D genome organization of the interphase nucleus in both normal and cancer cells.

Results: We describe a novel approach to study the distribution of all telomeres inside the nucleus of mammalian cells throughout the cell cycle. It is based on 3D telomere fluorescence in situ hybridization followed by quantitative analysis that determines the telomeres' distribution in the nucleus throughout the cell cycle. This method enables us to determine, for the first time, that telomere organization is cell-cycle dependent, with assembly of telomeres into a telomeric disk in the G2 phase. In tumor cells, the 3D telomere organization is distorted and aggregates are formed.

Conclusions: The results emphasize a non-random and dynamic 3D nuclear telomeric organization and its importance to genomic stability. Based on our findings, it appears possible to examine telomeric aggregates suggestive of genomic instability in individual interphase nuclei and tissues without the need to examine metaphases. Such new avenues of monitoring genomic instability could potentially impact on cancer biology, genetics, diagnostic innovations and surveillance of treatment response in medicine.

Show MeSH
Related in: MedlinePlus