Title:Dynamical Behaviors of the Transcriptional Network Including REST and miR-21 in Embryonic Stem Cells
Volume: 10
Issue: 1
Author(s): Qinbin He and Zengrong Liu
Affiliation:
Keywords:
Differentiation, self- renewal, embryonic stem cell, bistable switch.
Abstract: Recently several experiments have shown that REST is bound to the chromatin of miR-21,
and miR-21 inhibits the self-renewal of mouse embryonic stem (ES) cells by decreasing the expression
of SOX2, NANOG and OCT4. Thus, REST is believed to be a core transcription factor together with
miR-21 to regulate differentiation and self-renewal of ES cells. In this paper, a mathematical model is
established for investigating the roles of the REST-miR-21 regulatory pathway in the core regulatory
network of ES cells. Results show that REST plays a significant role of differentiation and self-renewal
by blocking the expression of miR-21, and the changes of expression of REST affects the expression of
miR-21, correspondingly leads to the bistable switching curve shift and the length of the bistable region changes, which
accordingly makes more opportunities of ES cells in the state of differentiation or self-renewal. Furthermore, results show
that the over-expression of REST or miR-21 will lead to an irreversible bistable switch. With appropriate combination of
two input external signals of embryonic stem cells, a more robust bistable switch can be obtained. In addition, a model of
proliferation cell population is given to explain the relationship between abnormal expression levels of REST (or miR-21)
and abnormal proliferation cell population, which will lead to a series of diseases, such as tumors.