A model explaining mRNA level fluctuations based on activity demands and RNA age

Cellular RNA levels are usually fluctuated and are affected by many factors. However, knowledge on the fundamental relationships between RNA abundance, environmental stimuli, and RNA activities is lacking, and the effects of RNA age on RNA levels remain unknown. A model based on activity demands and RNA age was developed to explore the mechanisms of RNA level fluctuations. With single cell time-series gene expression experimental data, we could assess transcription rates, RNA degradation rates, RNA life spans, RNA demands, accumulated transcription amounts, and accumulated RNA degradation amounts by this model. The model could also predict RNA levels under simulation backgrounds, such as stimuli leading to regular oscillations in RNA abundance, stable RNA levels over time being resulted from the long shortage of total RNA activity or uncontrollable transcription, and relationship between RNA levels and protein levels. Given explaining partly mechanisms of some RNA level fluctuations by the present model, further proves and suitable applications are expected.