Molecular Identification of Partial 189-bp Phytochelatin Synthase (PCS1) Gene from Eichhornia crassipes (Mart.) Solms

Abstract

Phytochelatins are glutathione-derived peptides involved in heavy-metal chelation and sequestration in plants. This study aimed to molecularly identify the phytochelatin synthase 1 (PCS1) gene in Eichhornia crassipes collected from the heavy-metal-contaminated Panteka stream in Kaduna, Nigeria, with an uncontaminated site serving as the control. Total RNA was extracted and used for cDNA synthesis by reverse-transcriptase polymerase chain reaction. A partial PCS1 fragment was amplified using gene-specific primers, and the PCR product was examined by agarose gel electrophoresis, purified, sequenced, and analysed using BLASTN and CLC Sequence Viewer. The sample from the contaminated site yielded the expected 189-bp amplicon, whereas no band was observed for the control plant sample or the negative control. Sequence analysis showed 100% identity with an E. crassipes phytochelatin synthase mRNA partial coding sequence in the NCBI database. The sequence also showed 82.86% identity with the E. crassipes chloroplast complete genome and the plastid NADH dehydrogenase subunit B gene partial coding sequence. Phylogenetic analysis placed the amplified sequence closest to the E. crassipes phytochelatin synthase mRNA partial coding sequence. These findings confirm the presence of a partial PCS1 sequence in E. crassipes from the contaminated site and provide a molecular basis for further investigation of its role in heavy-metal tolerance and phytoremediation.