Compositional Dynamics and Codon Usage Pattern of Myogenin (MyoG) Gene across Different Mammalian Species

MyoGenin (MyoG) is one of the key regulatory factors for controlling the generation of skeletal muscle. Codon usage bias (CUB) as a unique feature of the genome, can reveal the specific differences across species. Moreover, in the codon usage models of gene sequence, the dynamics of base composition can give a better understanding of the molecular mechanism and evolutionary relationships of a specific gene. Here, MyoG coding sequences of eight mammalian species were selected from the GenBank database to calculate the nucleotide composition (GC content) and genetic indexes, including effective number of codons (ENC), relative synonymous codon usage (RSCU) and relative codon bias score (RCBS) with R software. Results show that MyoG codon usage of different species is affected by GC bias, especially GC3s. Besides, the 23 codons with high codon usage frequencies are preferentially ended with G/C. Thereinto, the CUG, GUG, GCC, AUC and AGC with higher RSCU values are the most optimal codon in different species. The functional qualities of codons in Homo sapiens and Gallus gallus are similar, while those in Bos taurus and Ovis aries are similar. ENC vs. GC3s plot showed a significant negative correlation between the ENC and the GC3s (Pearson r = -0.934, P < 0.01). Moreover, a higher frequency of optimal codons (FOP) and RCBS value indicated a stronger codon bias in the MyoG gene, which is associated with its high expression levels. Our findings report an insight into the codon usage patterns of MyoG gene and will be useful for better understanding its function and structures.