Genetic characterization of Toxoplasma gondii isolates from chickens in India by GRA6 gene sequence analysis

Abstract

PCR-RFLP and nucleotide sequencing based genotyping of Toxoplasma gondii Indian isolates (Izatnagar and Chennai isolates and Chennai clone) vis-a vis RH-IVRI strain was conducted by targeting GRA6 as genetic marker. The 791 bp GRA6 product was PCR amplified from the genomic DNA of different T. gondii Indian isolates, including the RH-IVRI strain. Tru1I restriction endonuclease based PCR-RFLP of GRA6 sequence produced polymorphic digestion pattern that discriminated the virulent RH-IVRI strain (as type I) from the moderately virulent local isolates as type III. The PCR amplicon of T. gondii GRA6 from RH-IVRI strain as well as from the local isolates were cloned in cloning vector and custom sequenced. The nucleotide and deduced amino acid sequences of T. gondii isolates were aligned with that of the type I, II and III strains (RH, BEVER-LEY, ME49, C56, TONT and NED) available in public domain and analyzed in silico using MEGA version 4.0 software. Nucleotide sequencing and phylogenetic analysis of GRA6 marker from the Indian isolates revealed a close genetic relationship with type III strains of T. gondii. Further, detection of a single nucleotide polymorphism (SNP) at positions 162 and 171 of the GRA6 marker, established the lineage of Indian isolates as type III. This is the first report on characterization of T. gondii lineage as type III in selective chicken population of India based on PCR-RFLP and sequence analysis of GRA6 gene.

Genotypes of T. Gondii in Patients With Haematological Malignancies at a State Cancer Institute in South India

“…24 SAG3 locus sequencing of cryostocks of strains revealed genotype I 25 and sequencing of GRA6 locus showed genotype III. 26 However, since genotyping of the parasite in all these studies were based on single locus analysis, a more accurate picture of the prevailing genotype in the animals can only be obtained by a wider analysis on multiple loci.…”

Molecular cloning of SLC35D3 and analysis of its role during porcine intramuscular preadipocyte differentiation

“…The secondary structure of the deduced amino acid sequence was predicted by SOPMA (http:// npsa-pbil.ibcp.fr/) [29]. Phylogenetic analyses were performed using MEGA 5.1, applying the neighborjoining method [30]. Amino acid sequences from different species were aligned using DNAMAN V6 (LynnonBiosoft, Los Angeles, CA, USA) [31].…”

Restriction fragment length polymorphism-based genotyping of Toxoplasma gondii from autopsy-proven cases of acquired immunodeficiency syndrome-associated cerebral toxoplasmosis

“…[ 16 ] Indian studies on genetic characterization of the parasite have been restricted to locus-specific genotyping of animal strains. [ 17 18 ] In an earlier study, we carried out limited sequencing of four selected genetic loci (BTUB, GRA6, Alt. SAG2, SAG3) of T. gondii in 25 fatal cases of CT in HIV/AIDS patients.…”