Study of Codon Usage Patterns and Influencing Factors in Rice Yellow Mottle Virus Based on Coding Sequence Data

Abstract

Rice yellow mottle virus (RYMV), transmitted by chrysomelids, is one of the major viral pathogens that has devastated rice production in Sub-Saharan Africa. RYMV is a member of the genus Sobemoviruses in the family Solemoviridae and harbors a positive-sense single-stranded RNA (+ssRNA). Here, we used 50 RYMV strains, applying the codon usage bias (CUB). Both base content and relative synonymous codon usage (RSCU) analysis revealed that GC-ended codons were more frequently used in the genome of RYMV. Further low codon usage bias was observed from the effective number of codons (ENC) value. The neutrality plot analysis suggested the dominant factor of natural selection was involved in the structuring of CUB in RYMV. Based on RSCU values, the RYMV and its host relationship indicate that the RYMV develops codon usage patterns similar to its host. Generally, both natural selection and mutational pressure impact the codon usage pattern of the protein-coding genes in RYMV. This study is important because it characterized the codon usage pattern in the RYMV genomes and provided the necessary data for a basic evolutionary study on them. Additionally, we recommend that experiments such as whole genome sequencing (WGS) or dual RNA sequencing (DRS) should be considered in order to correlate these in-silico findings with viral diseases in the future.