Population Genetic Structure and Evidence of Demographic Expansion of the Ayu (Plecoglossus altivelis) in East Asia

Abstract

Plecoglossus altivelis (ayu) is an amphidromous fish widely distributed in Northeastern Asia from the East China Sea to the northern Japanese coastal waters, encompassing the Korean Peninsula within its range. The shore lines of northeastern region in Asia have severely fluctuated following glaciations in the Quaternary. In the present study, we investigate the population genetic structure and historical demographic change of P. altivelis at a population level in East Asia. Analysis of molecular variance (AMOVA) based on 244 mitochondrial control region DNA sequences clearly showed that as the sampling scope extended to a larger geographic area, genetic differentiation began to become significant, particularly among Northeastern populations. A series of hierarchical AMOVA could detect the genetic relationship of three closely located islands between Korea and Japan that might have been tightly connected by the regional Tsushima current. Neutrality and mismatch distribution analyses revealed a strong signature of a recent population expansion of P. altivelis in East Asia, estimated at 126 to 391 thousand years ago during the late Pleistocene. Therefore it suggests that the present population of P. altivelis traces back to its approximate demographic change long before the last glacial maximum. This contrasts our a priori expectation that the most recent glacial event might have the most crucial effect on the present day demography of marine organisms through bottleneck and subsequent increase of effective population size in this region

Postglacial range shift and demographic expansion of the marine intertidal snail Batillaria attramentaria

“…As explained earlier, historical population growths associated with the past climate during the Late Pleistocene changes were demonstrated in several phylogeographical studies of marine fish and mollusks in East Asia (Kojima et al 1997(Kojima et al , 2000(Kojima et al , 2004Liu et al 2006;Han et al 2008;Kwan et al 2012;Chiu et al 2013;Xue et al 2014). Taken together with the previous studies on the marine gastropods in East Asia, the Japanese turban shell Turbo cornutus (Kojima et al 1997(Kojima et al , 2000, the moon turban snail Lunella granulata (Chiu et al 2013), and the intertidal snail Batillaria attramentaria (Kojima et al 2004), our present study demonstrates the importance of the climate changes since the Late Pleistocene and the diversifying effect of the regional and ocean currents to both the demography and genetic differentiation of gastropods in this region.…”

“…; Kwan et al. ) and mollusks including the bivalve pen shell Atrina pectinata (Xue et al. ) and gastropod species such as the moon turban snail Lunella granulata (Chiu et al.…”

“…Although there is still a lack of phylogeographic studies on the issue of historical demography of marine taxa in East Asia, several examples could be found from marine fishes and mollusks. Evident are genetic signals of historical demographic growths in fish species (Liu et al 2006;Han et al 2008;Kwan et al 2012) and mollusks including the bivalve pen shell Atrina pectinata (Xue et al 2014) and gastropod species such as the moon turban snail Lunella granulata (Chiu et al 2013), the Japanese turban shell Turbo cornutus (Kojima et al 1997(Kojima et al , 2000, and the intertidal snail Batillaria attramentaria (Kojima et al 2004). In addition to the evidence of population expansions, all the latter gastropod species commonly showed that the current population genetic patterns of them have been primarily shaped by the influence of regional geographic barriers generated by lands and divergent oceanic currents.…”

Mitochondrial DNA sequence analysis from multiple gene fragments reveals genetic heterogeneity of Crassostrea ariakensis in East Asia

“…In addition, the IR site in Japan, SR and KSR sites at the southern tip of Korea were significantly genetically differentiated from most other sites within the clade containing northern population as shown by pairwise U ST analyses. While the overall genetic pattern of C. ariakensis across the three regions (China, Korea and Japan), may involve the KC and TC currents having a major influence, the local KS current may also play a role as has been suggested for a number of aquatic organisms studied across these regions (Kang et al 2012;Kwan et al 2012;Yang et al 2009). The KD and SD sites are situated within a closed bay area (Fig.…”

A Y-linked anti-Müllerian hormone type-II receptor is the sex-determining gene in ayu, Plecoglossus altivelis

“…Ayu (or sweetfish), Plecoglossus altivelis , is widely distributed in East Asia, especially in Japan, Korea, Taiwan and China [ 15 – 17 ]. Ayu belongs to the order Osmeriformes and the family Osmeridae.…”