Micro-droplet model for recursive growth and division dynamics of the cell

T. Ichii¹, H. Suzuki^1,2 and T. Yomo^1,2,3a

¹ ERATO, Japan Science and Technology Agency - 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
² Graduate School of Information Science and Technology, Osaka University - 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
³ Graduate School of Frontier Biosciences, Osaka University - 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan

^a yomo@ist.osaka-u.ac.jp

Received: 1 July 2011
Accepted: 3 October 2011

Abstract

Living cells replicate by passing through cycles of growth and division, and they act as containers for chemical reactions. To determine basic properties of such recursively growing and dividing micro-compartments, we constructed a model system in a micro-fluidic device. In this system, droplets in a water-in-oil emulsion underwent cycles of fusion and subsequent division with nutrient-mimicking droplets. We found that repeating the combinations of growth (by fusion) and division of the droplets brought about their steady size distribution that had a skewed shape, similar to that which had been observed for proliferating cells. Our numerical analysis suggested that the skewness was originated from stochasticity in the addition of volumes in the growth process.