Figure 2

Degree distribution of the miRNA-mRNA network. A) out-degree distribution of the miRNA-mRNA network. Most of miRNAs are lowly connected and only a few are relatively highly connected. The examination of the out-degree distribution of the miRNA-mRNA network reveals a power law with a exponent of -0.6985 and R² =0.8324. B) in-degree distribution of the miRNA-mRNA network. In-degree is defined as the number of regulatory miRNAs for each target, signifying an exponential distribution with an exponent of -0.3866 and R² = 0.9729. The exponent described the distribution of degrees. R² is the coefficient of determination, which indicates how well data points fit a line or curve. An R² of 1 indicates that the line perfectly fits the data. The larger R² is, the better the data fit the line.