School of Sciences, Hainan University, Haikou, 570228, Hainan, People's Republic of China.
Department of Neurology, The First Affiliated Hospital, University of South China, HengYang, 421001, Hunan, People's Republic of China.
Biosystems. 2022 Apr;214:104648. doi: 10.1016/j.biosystems.2022.104648. Epub 2022 Feb 23.
Genes integrate many different sources of noise to adapt their survival strategy with energy costs, but how this noise impacts gene phenotype switching is not fully understood. Here, we refine a mechanistic model with multiplicative and additive coloured noise and analyse the influence of noise strength (NS) and autocorrelation time (AT) on gene phenotypic diversity. Different from white noise, we found that in the autocorrelation time-scale plane, increasing the multiplicative noise will broaden the bimodal region of the gene product, and additive noise will induce bimodal region drift from the lower level to the higher level, while the AT will promote this transition. Specifically, the effect of AT on gene expression is similar to a feedback loop; that is, the AT of multiplicative noise will elongate the mean first passage time (MFPT) from the low stable state to the high stable state, but it will reduce the MFPT from the high stable state to the low stable state, and the opposite is true for additive noise. Moreover, these transitions will violate the detailed equilibrium and then consume energy. By effective topology network reconstruction, we found that when the NS is small, the more obvious the bimodality is, the lower the energy dissipation; however, when the NS is large, it will consume more energy with a tendency for bimodality. The overall analysis implies that living organisms will utilize noise strength and its autocorrelation time for better survival in complex and fluctuating environments.
基因整合了许多不同的噪声源，以根据能量成本调整其生存策略，但噪声如何影响基因表型转换还不完全清楚。在这里，我们用乘法和加法有色噪声细化了一个机械模型，并分析了噪声强度（NS）和自相关时间（AT）对基因表型多样性的影响。与白噪声不同，我们发现，在自相关时间尺度平面上，增加乘法噪声会拓宽基因产物的双峰区域，而加法噪声会导致双峰区域从低水平漂移到高水平，而 AT 会促进这种转变。具体来说，AT 对基因表达的影响类似于反馈回路；也就是说，乘法噪声的 AT 会延长从低稳定态到高稳定态的平均首次通过时间（MFPT），但会减少从高稳定态到低稳定态的 MFPT，而加法噪声则相反。此外，这些转变将违反详细平衡，然后消耗能量。通过有效的拓扑网络重建，我们发现，当 NS 较小时，双峰性越明显，能量消耗越低；然而，当 NS 较大时，双峰性会消耗更多的能量。总的来说，分析表明，生物体会利用噪声强度及其自相关时间，在复杂和波动的环境中更好地生存。
