Mitochondrial DNA Diversity of Terubok (Tenualosa toli) from Daro and Mukah, Sarawak Inferred by Partial Cytochrome b (Cyt-B)

Abstract

Terubok (Tenualosa toli) is one of Malaysia commercially important fish which is found mainly in Sarawak. Their numbers of catch have been declining in the past 15 years due to heavy exploitation. Hence, a study was done to determine the mitochondrial genetic diversity of T. toli from Daro and Mukah, Sarawak inferred by partial Cytochrome b gene. DNA extraction was done on 84 T. toli samples. PCR amplification using Cyt-b primers had been carried out and sequence of 469 bp length was obtained from each sample. Next, phylogenetic analysis was performed to study the relationship among the individuals. The genetic diversity of the population was determined through the haplotype and nucleotide diversity. Result of the study showed that the Haplotype Diversity (HD) of T. toli was relatively low for Daro (Hd = 0.232) and Mukah populations (Hd = 0.178). The nucleotide diversity was also low for both populations. Moreover, only nine haplotypes were identified from the 84 individuals. A single haplotype was shared amongst 76 individuals. These findings correlate with previous study that showed the number of the fish caught had declined drastically and might cause a genetic deprivation towards its population. Comparably, maximum likelihood analysis revealed that two T. toli individuals were separated from the main clade, suggesting that these two individuals might come from another Terubok population. Genetic diversity of the mitochondrial DNA Cytochrome b of the T. toli obtained in this study would be useful in the implementation of conservation and fisheries management of this species in Sarawak.

Species identification and molecular analysis of terubuk fish from Bengkalis strait (Riau, Indonesia) using COI mitochondrial gene as a barcoding marker

“…The seven T.macrura samples investigated in this study exhibited low genetic variation which was indicated by 3-5 bp (1.13%) nucleotide differences with one amino acid divergence even though the haplotype diversity was high. The low genetic variation correlates with the previous study conducted by AZIZ et al (2015) who studied the genetic diversity of T. toli in Daru and Mukah (Sarawak, Malaysia) using cytochrome b mitochondrial gene (Cyt-b) and by ARJUNAIDI et al (2016) who investigated the genetic diversity of T. ilisha from Perak River (Malaysia) using COI and 16S mitochondrial genes. These previous studies reported that the number of the terubuk fish caught had decreased drastically and might cause a decrease in genetic variation in the population.…”

“…This divergence might indicate that the three individuals may come from other populations due to migration behaviour. The species included in the genus Tenualosa commonly have long-distance migration (AZIZ et al, 2015;ARJUNAIDI et al, 2016). Therefore, there is a possibility of admixture among T. macrura from a different population.…”

Application of the Cytochrome-b gene region in Population Study of Striped Snakehead (Channa striata) by Molecular Approach

“…The Cyt-b sequence also completes the confirmation of the species in this study as C. striata species. This Cyt-b sequence has been widely used in studies of diversity and population genetics in various types of fish (Aziz et al 2015, Kartavtsev 2011, Sun et al 2019. Population studies carried out in this study showed that C. striata from four sites had similarities in their nucleotide base sequences.…”

Diagnostic locus for identification of silverside hybrids (odontesthes humensis and odontesthes bonariensis) in a natural population

“…In turn, the analysis of the mitochondrial genome, either alone or in combination with other nuclear markers, such as microsatellites, is widely used in population structure elucidation studies, as it presents maternal inheritance and the repertoire of encoded genes is extremely conserved (Aziz et al, 2015;Satoh et al, 2016). Mitochondrial markers are widely used in fish studies, and a large number of universal primers are available to amplify different genes from the mitochondrial genome of many fish species, as they appear not to undergo recombination and evolve about 10 times faster than the nuclear genome (Kochzius, 2009).…”