The geometry of proliferating dicot cells

Area of Science:

• Plant biology
• Developmental biology
• Cell biology

Background:

• Understanding plant tissue growth requires knowledge of cell division and size regulation.
• Cell size and cell cycle duration are key factors influencing plant development.

Purpose of the Study:

• To investigate the distributions of cell size and cell cycle duration in two-dimensional expanding plant tissues.
• To analyze how cell division impacts cell size variability in plant epidermis.

Main Methods:

• Plastic imprints of leaf epidermis from three dicot plants (jade, impatiens, begonia) were analyzed.
• Cell outlines were measured to determine average cell size, standard deviation, and coefficient of variance (CV).
• Cell cycle durations were estimated by reconstructing cell sizes before and after division.

Main Results:

• The coefficient of variance (CV) for cell size was lower for mother cells than daughter cells, and lowest for all cells.
• An equation was developed to describe the probability distribution of cell sizes in plant tissues.
• Cell cycle durations exhibited an asymmetric bell-shaped probability distribution.
• Unequal cell division resulted in an average 11.6% size difference between daughter cells.

Conclusions:

• The range of cell size appears to be more critically regulated than the size of individual cells at specific times.
• Cell size variation and unequal division contribute to the overall growth dynamics of plant tissues.
• The findings provide insights into the regulatory mechanisms governing cell proliferation and expansion in plants.