Population variation in the mitochondrial cytochrome b gene of the orange roughy Hoplostethus atlanticus and the hoki Macruronus novaezelandiae

Lack of divergence in the mitochondrial cytochromebgene betweenMacruronusspecies (Pisces: Merlucciidae) in the Southern Hemisphere

“…Symmetrical amplification of the mitochondrial DNA cytochrome b gene was performed via the polymerase chain reaction (PCR, Saiki et al 1988) following standard protocols (Palumbi 1996). A 500 base pair (bp) portion of the mtDNA cytochrome b was amplified using the primers, tGludg (TGACTTGAARAACCAYCGTTG, Palumbi et al 1991) and Cyb2 (CCCTCAGAATGA TATTTGTCCTCA, Kocher et al 1989) following Baker et al (1995). The PCR profile consisted of one initial cycle of strand denaturation at 94°C for 1 min, primer annealing at 48°C for 1 min, and extension at 72°C for 1 min, followed by 35 cycles of 94°C for 30 s, 52°C for 30 s, and 72°C for 1 min (Baker et al 1995).…”

“…A 500 base pair (bp) portion of the mtDNA cytochrome b was amplified using the primers, tGludg (TGACTTGAARAACCAYCGTTG, Palumbi et al 1991) and Cyb2 (CCCTCAGAATGA TATTTGTCCTCA, Kocher et al 1989) following Baker et al (1995). The PCR profile consisted of one initial cycle of strand denaturation at 94°C for 1 min, primer annealing at 48°C for 1 min, and extension at 72°C for 1 min, followed by 35 cycles of 94°C for 30 s, 52°C for 30 s, and 72°C for 1 min (Baker et al 1995). PCR amplification products were purified from primers and nucleotides using exonuclease I (Exo I) and shrimp alkaline phosphatase (SAP, Werle et al 1994).…”

“…Sequences were aligned and compared to previously reported cytochrome b sequences of M. novaezelandiae obtained at three fishing grounds around New Zealand (west coast of South Island (n = 9), Cook Strait (n = 9), and Chatham Rise (n = 1)) and one in Australia, off the west coast of Tasmania (n = 8) (Baker et al 1995). Comparisons of the two sets of sequences were performed using MacClade (version 4.0, Maddison & Maddison 2000) to identify variable sites and define haplotypes.…”

“…1 General geographic distribution of Macruronus novaezelandiae and M. magellanicus (shaded). Location of sampling sites for M. novaezelandiae (AU, Australia; NZ, New Zealand, from Baker et al (1995)) and M. magellanicus (CH, southern Chile). Map not to scale.…”

“…We compare sequences of mitochondrial DNA cytochrome b gene from M. magellanicus from the Chilean coast and M. novaezelandiae from New Zealand-Australia using new and previously published sequences (Baker et al 1995). This molecular marker has been widely used in establishing systematic relationships of fish (Stepien & Kocher 1997), but has not been used to establish systematic relationship of the Macruronus genus.…”