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Power law relationship between cell cycle duration and cell volume in the early embryonic development of Caenorhabditis elegans.

Arata Y, Takagi H, Sako Y, Sawa H - Front Physiol (2015)

Bottom Line: Here, we found that the relationship between cell cycle duration and cell size in Caenorhabditis elegans embryos exhibited a power law distribution.Furthermore, we found that the volume ratio between the nucleus and cell exhibited a power law relationship in the size-correlated classes.Thus, our quantitative measurements shed a light on the possibility that early embryonic C. elegans cell cycle duration is coordinated with cell size as a result of geometric constraints between intracellular structures.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Cell Fate Decision, Center for Developmental Biology, RIKEN Hyogo, Japan ; Cellular Informatics Laboratory, RIKEN Saitama, Japan.

ABSTRACT
Cell size is a critical factor for cell cycle regulation. In Xenopus embryos after midblastula transition (MBT), the cell cycle duration elongates in a power law relationship with the cell radius squared. This correlation has been explained by the model that cell surface area is a candidate to determine cell cycle duration. However, it remains unknown whether this second power law is conserved in other animal embryos. Here, we found that the relationship between cell cycle duration and cell size in Caenorhabditis elegans embryos exhibited a power law distribution. Interestingly, the powers of the time-size relationship could be grouped into at least three classes: highly size-correlated, moderately size-correlated, and potentially a size-non-correlated class according to C. elegans founder cell lineages (1.2, 0.81, and <0.39 in radius, respectively). Thus, the power law relationship is conserved in Xenopus and C. elegans, while the absolute powers in C. elegans were different from that in Xenopus. Furthermore, we found that the volume ratio between the nucleus and cell exhibited a power law relationship in the size-correlated classes. The power of the volume relationship was closest to that of the time-size relationship in the highly size-correlated class. This correlation raised the possibility that the time-size relationship, at least in the highly size-correlated class, is explained by the volume ratio of nuclear size and cell size. Thus, our quantitative measurements shed a light on the possibility that early embryonic C. elegans cell cycle duration is coordinated with cell size as a result of geometric constraints between intracellular structures.

No MeSH data available.


Related in: MedlinePlus

Power law relationship between the nuclear and cell volume. Relationship between nuclear and cell volume in size-correlated classes (AB, MS, C, and P) is shown in linear (A) and double logarithmic (B) plots. Cell volumes were determined by the integral approach with error correction, whereas nuclear volumes were determined by the formula approach in three wild-type embryos. Data in logarithmic scale were fitted to the formula, y = a + bx, by the linear least-squares method. Degree of freedom in fitting was 75.
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Figure 5: Power law relationship between the nuclear and cell volume. Relationship between nuclear and cell volume in size-correlated classes (AB, MS, C, and P) is shown in linear (A) and double logarithmic (B) plots. Cell volumes were determined by the integral approach with error correction, whereas nuclear volumes were determined by the formula approach in three wild-type embryos. Data in logarithmic scale were fitted to the formula, y = a + bx, by the linear least-squares method. Degree of freedom in fitting was 75.

Mentions: To explain the C. elegans power law T–V relationship, we focused on the relationship between the cell and nuclear volumes. We plotted the nuclear vs. cell volumes for cells in size-correlated AB, MS, C, and P lineages (Figure 5A). The relationship between the nuclear and cell volumes was non-linear in a linear plot, and showed a linear relationship in a double logarithmic plot (Figure 5B). The relationship was well-fitted by a power law model (R2 = 0.94; Figure 5B). Nuclear volume varied with cell volume, in a power law relationship with a slope of 0.63 (Figure 5B). If the volumes of the two spheres varied in a corresponding manner, then the power was unity; thus, the C. elegans relationship between the nuclear and cell volumes was allometric. Supposing that a factor critical for cell cycle regulation is transported between the nucleus and cytoplasm, we considered the ratio of the nuclear volume (Vn) to the cell volume (Vc). The power of the volume ratio was −0.37 (Vn /Vc ∝ V0.63c /Vc = V−0.37c). We found that the absolute value of the power of the volume ratio (0.37) was closest to that of the T–V relationship in the highly size-correlated class (C and P lineages) (0.41), indicating a strong correlation with the volume ratio between the nucleus and cell.


Power law relationship between cell cycle duration and cell volume in the early embryonic development of Caenorhabditis elegans.

Arata Y, Takagi H, Sako Y, Sawa H - Front Physiol (2015)

Power law relationship between the nuclear and cell volume. Relationship between nuclear and cell volume in size-correlated classes (AB, MS, C, and P) is shown in linear (A) and double logarithmic (B) plots. Cell volumes were determined by the integral approach with error correction, whereas nuclear volumes were determined by the formula approach in three wild-type embryos. Data in logarithmic scale were fitted to the formula, y = a + bx, by the linear least-squares method. Degree of freedom in fitting was 75.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4309120&req=5

Figure 5: Power law relationship between the nuclear and cell volume. Relationship between nuclear and cell volume in size-correlated classes (AB, MS, C, and P) is shown in linear (A) and double logarithmic (B) plots. Cell volumes were determined by the integral approach with error correction, whereas nuclear volumes were determined by the formula approach in three wild-type embryos. Data in logarithmic scale were fitted to the formula, y = a + bx, by the linear least-squares method. Degree of freedom in fitting was 75.
Mentions: To explain the C. elegans power law T–V relationship, we focused on the relationship between the cell and nuclear volumes. We plotted the nuclear vs. cell volumes for cells in size-correlated AB, MS, C, and P lineages (Figure 5A). The relationship between the nuclear and cell volumes was non-linear in a linear plot, and showed a linear relationship in a double logarithmic plot (Figure 5B). The relationship was well-fitted by a power law model (R2 = 0.94; Figure 5B). Nuclear volume varied with cell volume, in a power law relationship with a slope of 0.63 (Figure 5B). If the volumes of the two spheres varied in a corresponding manner, then the power was unity; thus, the C. elegans relationship between the nuclear and cell volumes was allometric. Supposing that a factor critical for cell cycle regulation is transported between the nucleus and cytoplasm, we considered the ratio of the nuclear volume (Vn) to the cell volume (Vc). The power of the volume ratio was −0.37 (Vn /Vc ∝ V0.63c /Vc = V−0.37c). We found that the absolute value of the power of the volume ratio (0.37) was closest to that of the T–V relationship in the highly size-correlated class (C and P lineages) (0.41), indicating a strong correlation with the volume ratio between the nucleus and cell.

Bottom Line: Here, we found that the relationship between cell cycle duration and cell size in Caenorhabditis elegans embryos exhibited a power law distribution.Furthermore, we found that the volume ratio between the nucleus and cell exhibited a power law relationship in the size-correlated classes.Thus, our quantitative measurements shed a light on the possibility that early embryonic C. elegans cell cycle duration is coordinated with cell size as a result of geometric constraints between intracellular structures.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Cell Fate Decision, Center for Developmental Biology, RIKEN Hyogo, Japan ; Cellular Informatics Laboratory, RIKEN Saitama, Japan.

ABSTRACT
Cell size is a critical factor for cell cycle regulation. In Xenopus embryos after midblastula transition (MBT), the cell cycle duration elongates in a power law relationship with the cell radius squared. This correlation has been explained by the model that cell surface area is a candidate to determine cell cycle duration. However, it remains unknown whether this second power law is conserved in other animal embryos. Here, we found that the relationship between cell cycle duration and cell size in Caenorhabditis elegans embryos exhibited a power law distribution. Interestingly, the powers of the time-size relationship could be grouped into at least three classes: highly size-correlated, moderately size-correlated, and potentially a size-non-correlated class according to C. elegans founder cell lineages (1.2, 0.81, and <0.39 in radius, respectively). Thus, the power law relationship is conserved in Xenopus and C. elegans, while the absolute powers in C. elegans were different from that in Xenopus. Furthermore, we found that the volume ratio between the nucleus and cell exhibited a power law relationship in the size-correlated classes. The power of the volume relationship was closest to that of the time-size relationship in the highly size-correlated class. This correlation raised the possibility that the time-size relationship, at least in the highly size-correlated class, is explained by the volume ratio of nuclear size and cell size. Thus, our quantitative measurements shed a light on the possibility that early embryonic C. elegans cell cycle duration is coordinated with cell size as a result of geometric constraints between intracellular structures.

No MeSH data available.


Related in: MedlinePlus