Gaining Insights into the Codon Usage Patterns of TP53 Gene across Eight Mammalian Species

Mazumder, Tarikul Huda; Chakraborty, Supriyo

The relative synonymous codon usage values of 59 codons for TP53 gene across eight mammalian species were analyzed excluding the codons ATG (methionine) and TGG (tryptophan). In our calculation RSCU value greater than 1.0 represents that the particular codon is used more frequently and less than 1.0 represents the less frequently used codon for the corresponding amino acid. The RSCU value greater than 1.6 indicates over represented codon for the corresponding amino acid. The overall RSCU values in the selected coding sequences of TP53 gene revealed that 25 codons were most frequently used among the 59 codons and the most predominantly used codons were G/C-ending compared to A/T-ending (Table 2) . Besides, it was observed that C-ending codon was mostly favored compared to G-ending codon in the coding sequence of TP53 gene among the selected mammalian species. Our results showed marked similarities as reported by Dass et al., (2012) in serotonin receptor gene family from different mammalian species [35] . Further, clustering analysis of RSCU values (Fig. 3) depicted that the codon GCC, CGC (except Rattus norvegicus), ATC (except Tupaia chinensis), CTG, ACC (except Rattus norvegicus, Macaca mulatta), GTG (except Felis catus) were displayed as the over represented codons (RSCU>1.6). The highest RSCU value was found for the codon CTG for leucine amino acid in all TP53 genes across mammalian species. The codon ATA showed the RSCU value zero because natural selection has not favored this codon in TP53 gene across mammalian species.