title: Expression levels and codon usage patterns in nuclear genes of the filarial nematode Wucheraria bancrofti and the blood fluke Schistosoma haematobium.
abstract: Synonymous codons are used with different frequencies, a phenomenon known as codon bias, which exists in many genomes and is mainly resolute by mutation and selection. To elucidate the genetic characteristics and evolutionary relationship of Wucheraria bancrofti and Schistosoma haematobium we examined the pattern of synonymous codon usage in nuclear genes of both the species. The mean overall GC contents of W. bancrofti and S. haematobium were 43.41 and 36.37%, respectively, which suggests that genes in both the species were AT rich. The value of the High Effective Number of Codons in both species suggests that codon usage bias was weak. Both species had a wide range of P3 distribution in the neutrality plot, with a significant correlation between P12 and P3. The codons were closer to the axes in correspondence analysis, suggesting that mutation pressure influenced the codon usage pattern in these species. We have identified the more frequently used codons in these species, most codons ending with an A or T. The nucleotides A/T and C/G were not proportionally used at the third position of codons, which reveals that natural selection might influence the codon usage patterns. The regression equation of P12 on P3 suggests that natural selection might have played a major role, while mutational pressure played a minor role in codon usage pattern in both species. These results form the basis of exploring the evolutionary mechanisms and the heterologous expression of medically important proteins of W. bancrofti and S. haematobium.
authors.affiliation: Department of Biotechnology,Assam University,Silchar-788011,Assam,India.
authors.forename: G A
authors.initials: GA
authors.lastname: Mazumder
authors.affiliation: Department of Biotechnology,Assam University,Silchar-788011,Assam,India.
authors.forename: A
authors.initials: A
authors.lastname: Uddin
authors.affiliation: Department of Biotechnology,Assam University,Silchar-788011,Assam,India.
authors.forename: S
authors.initials: S
authors.lastname: Chakraborty
mesh_terms: D000818:Animals; D001482:Base Composition; D003062:Codon; D020869:Gene Expression Profiling; D017238:Genes, Helminth; D012548:Schistosoma haematobium / Q000235:genetics*; D014958:Wuchereria bancrofti / Q000235:genetics*
chemical_list: D003062:Codon