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111.
112.
Asuka Takaishi Andrey E. Kozhevnikov Zoya V. Kozhevnikova Hajime Ikeda Noriyuki Fujii Akiko Soejima 《Ecology and evolution》2019,9(12):7262-7272
The genetic diversity and structure of Pulsatilla cernua, a continental‐grassland relict, were investigated using variations in chloroplast DNA (cpDNA) and microsatellites of nuclear DNA. In the analyses of three cpDNA regions, 17 haplotypes were found in 24 populations of P. cernua from Japan, Korea, and Russia. Although the route and time of migration between the continent of Asia and Japan could not be well resolved, the cpDNA haplotype network suggests the existence of several ancient lineages in Japan and a recent secondary migration from Japan to the continent. Microsatellite analyses did not indicate genetic structure among the Japanese populations, indicating the existence of gene flow across the distribution area until recently. These results indicate that the present fragmentation of P. cernua in Japan may reflect a rapid, recent reduction from a previously large, continuous distribution. 相似文献
113.
M. F. DOCKER G. R. HAAS D. H. GOODMAN S. B. REID D. D. HEATH 《Molecular ecology resources》2007,7(2):350-353
We developed five polymerase chain reaction‐based markers that detect variation in the mitochondrial genome of the Pacific lamprey, Entosphenus tridentatus, across most of its range. Two gene fragments (ND2 and ND5) were amplified and digested with three and two restriction enzymes, respectively, detecting sequence variation at 18 sites (ND2 = 13; ND5 = 5) and yielding 29 composite haplotypes among 1246 lampreys. These sequence‐based markers will be useful in a range of phylogeographical and population genetic studies. 相似文献
114.
Alvinella pompejana, the so-called Pompeii worm (Desbruyères and Laubier, 1980), is found exclusively in association to high temperature venting,
at the surface of hydrothermal chimneys of the East Pacific Rise. The main characteristics of this emblematic species is its
tolerance to high temperature but its ability to colonize extremely hot substrates has been the subject of much controversy.
In the last decade, new tools allowing in situ and in vivo investigation have been determinant in the understanding of the
strategies and adaptations required to colonize such an extremely hot environment. New data relative to the characterization
of the animal habitat conditions, on one hand, to the molecular adaptations of this organism and the colonization processes
by this species, on the other hand, are now available. Advanced methods and tools, that have fostered the physico-chemical
characterization of vent habitats in recent years, are first reviewed. Factors controlling the physico-chemical variability
of vent habitats and the threats A. pompejana might effectively face are discussed. The exceptional thermotolerance of this species and the maximum temperature it could
sustain are then considered in the light of molecular data relative to its collagen stability. Life history traits as well
as biological controls on tube micro-habitat conditions are discussed on the basis of new in situ and in vivo experiments
and characterization. Finally, the current knowledge and opened questions related to the molecular adaptations to chemical
stresses are briefly stated. The ability of Alvinella pompejana to colonize these substrates is far from being fully understood, but the exceptional properties of its extracellular biopolymers
and the behavior of the worm can be now considered as major clues in the colonization process. Alvinella pompejana could thus stand at the limits authorized for its biological machinery in a highly dynamic environment where temperature
can readily reach lethal values, but where temperature regulation by the animal itself would prevent exposure to deleterious
thermal spikes. The dynamic system associating this pioneer species and its associated microflora might be viewed as a key
to the subsequent colonization of these environments by less tolerant species, highlighting A. pompejana as a new type of ecosystem bioengineer. 相似文献
115.
Tree-ring cellulose oxygen isotope ratios (δ18O) is a well-established proxy for hydroclimatic conditions in monsoon Asia. We reconstructed June–October relative humidity (RHJ–O) variations from 1808 to 2017, based on tree-ring cellulose δ18O data, which explain 46.2% of the actual RH variance in the Nanyue region, south–central China. Extreme wet events occurred frequently prior to the 1900s, but there have been more extreme dry events since the 1900s, apart from the late 1930s and early 1950s. Periodicity analysis revealed that the reconstructed RHJ–O records show obvious 15–30 years cycles from the 1830–1970s. The multi-decadal signals may reflect the effect of the Pacific Decadal Oscillation (PDO) on hydroclimate. In the positive PDO phase, there is drying in south–central China, which is related to a weaker East Asian summer monsoon (EASM) via the Pacific–Japan teleconnection. The decadal signal has weakened since the 1970s. In addition, the reconstructed RHJ–O record shows strong interannual variations, which may be related to the Central Pacific El Niño–Southern Oscillation (CP ENSO). During extreme CP El Niño events, there is a weaker EASM due to the Pacific–Japan teleconnection, and the study site experienced drought. Our reconstructed moisture record is characterized by a decreasing influence from the PDO and increasing influence from the CP ENSO in recent decades. Moreover, the frequency of CP ENSO events is projected to increase under anthropogenic warming. Consequently, more extreme droughts which are related to CP ENSO events may increase in the south–central China in near future. 相似文献
116.
《遗传学报》2022,49(1):54-62
The global “myopia boom” has raised significant international concerns. Despite a higher myopia prevalence in Asia, previous large-scale genome-wide association studies (GWASs) were mostly based on European descendants. Here, we report a GWAS of spherical equivalent (SE) in 1852 Chinese Han individuals with extreme SE from Guangzhou (631 < ?6.00D and 574 > 0.00D) and Wenzhou (593 < ?6.00D and 54 > ?1.75D), followed by a replication study in two independent cohorts with totaling 3538 East Asian individuals. The discovery GWAS and meta-analysis identify three novel loci, which show genome-wide significant associations with SE, including 1q25.2 FAM163A, 10p11.22 NRP1/PRAD3, and 10p11.21 ANKRD30A/MTRNR2L7, together explaining 3.34% of SE variance. 10p11.21 is successfully replicated. The allele frequencies of all three loci show significant differences between major continental groups (P < 0.001). The SE reducing (more myopic) allele of rs10913877 (1q25.2 FAM163A) demonstrates the highest frequency in East Asians and much lower frequencies in Europeans and Africans (EAS = 0.60, EUR = 0.20, and AFR = 0.18). The gene-based analysis additionally identifies three novel genes associated with SE, including EI24, LHX5, and ARPP19. These results provide new insights into myopia pathogenesis and indicate the role of genetic heterogeneity in myopia epidemiology among different ethnicities. 相似文献
117.
《遗传学报》2022,49(11):1053-1063
The domestication and artificial selection of wild boars have led to dramatic morphological and behavioral changes, especially in East Chinese (ECN) pigs. Here, we provide insights into the population structure and current genetic diversity of representative ECN pig breeds. We identify a 500-kb region containing six tooth development-relevant genes with almost completely different haplotypes between ECN pigs and Chinese wild boars or European domestic pigs. Notably, the c.195A>G missense mutation in exon 2 of AMBN may cause alterations in its protein structure associated with tusk degradation in ECN pigs. In addition, ESR1 may play an important role in the reproductive performance of ECN pigs. A major haplotype of the large lop ear-related MSRB3 gene and eight alleles in the deafness-related GRM7 gene may affect ear morphology and hearing in ECN pigs. Interestingly, we find that the two-end black (TEB) coat color in Jinhua pigs is most likely caused by EDNRB with genetic mechanisms different from other Chinese TEB pigs. This study identifies key loci that may be artificially selected in Chinese native pigs related to the tusk, coat color, and ear morphology, thus providing new insights into the genetic mechanisms of domesticated pigs. 相似文献
118.
Osamu Miura Gen Kanaya Shizuko Nakai Hajime Itoh Satoshi Chiba 《International journal for parasitology》2019,49(13-14):1023-1028
Trematode parasites have complex life cycles and use a variety of host species across different trophic levels. Thus, they can be used as indicators of disturbance and recovery of coastal ecosystems. Estuaries on the Pacific coast of northeastern Japan were heavily affected by the 2011 Tohoku earthquake tsunami. To evaluate the effect of the tsunami on the trematode community, we examined trematodes in the mud snail, Batillaria attramentaria, at five study sites (three sites severely exposed to the tsunami and two sites sheltered from the tsunami) in Sendai Bay for 2 years prior to and 8 years after the tsunami. While the trematode prevalence decreased at all study sites, the species richness decreased only at the sites exposed to the tsunami. Although parasitism increased over the study period post-tsunami, the community had not fully recovered 8 years after the event. Trematode community structure has changed every year since the tsunami and has not stabilised. This could be explained by the alteration of first and second intermediate host communities. Our study suggests that it will take more time for the recovery of the trematode community and the associated coastal ecosystem in the Tohoku region. 相似文献
119.
Ga Hun Boo Ying‐Xiong Qiu Jung Yeon Kim Put O. Ang Samuel Bosch Olivier De Clerck Peimin He Atsushi Higa Bangqin Huang Kazuhiro Kogame Shao‐Lun Liu Tu van Nguyen Shoichiro Suda Ryuta Terada Kathy Ann Miller Sung Min Boo 《Journal of phycology》2019,55(6):1319-1334
The evolutionary and population demographic history of marine red algae in East Asia is poorly understood. Here, we reconstructed the phylogeographies of two upper intertidal species endemic to East Asia, Gelidiophycus divaricatus and G. freshwateri. Phylogenetic and phylogeographic inferences of 393 mitochondrial cox1, 128 plastid rbcL, and 342 nuclear ITS2 sequences were complemented with ecological niche models. Gelidiophycus divaricatus, a southern species adapted to warm water, is characterized by a high genetic diversity and a strong geographical population structure, characteristic of stable population sizes and sudden reduction to recent expansion. In contrast, G. freshwateri, a northern species adapted to cold temperate conditions, is genetically relatively homogeneous with a shallow population structure resulting from steady population growth and recent equilibrium. The overlap zone of the two species roughly matches summer and winter isotherms, indicating that surface seawater temperature is a key feature influencing species range. Unidirectional genetic introgression was detected at two sites on Jeju Island where G. divaricatus was rare while G. freshwateri was common, suggesting the occurrence of asymmetric natural hybrids, a rarely reported event for rhodophytes. Our results illustrate that Quaternary climate oscillations have left strong imprints on the current day genetic structure and highlight the importance of seawater temperature and sea level change in driving speciation in upper intertidal seaweed species. 相似文献
120.
Anita C. Kroska Nathan Wolf Roman Dial Bradley P. Harris 《Journal of fish biology》2019,95(2):647-650
Cross-contamination of epidermal mucus was assessed at three sampling locations on the bodies of Pacific halibut Hippoglossus stenolepis by inducing contact between fish coated with labelled synthetic mucus and non-treated fish. Results indicate a positive relationship between sampling site exposure and sample contamination and that mucous sample cross-contamination can be mitigated by sampling in a location protected from external contact. 相似文献