The First Genome-Wide Survey of Shortbelly Eel (Dysomma anguillare Barnard, 1923) to Provide Genomic Characteristics, Microsatellite Markers and Complete Mitogenome Information.

Dysomma anguillare is a demersal eel widespread distributing in tropical waters of the Indo-West Pacific and Atlantic. As an important component of the coastal fishery and marine ecosystem, the lack of genomic information for this species severely restricts the progress of relevant researches. In this study, the abecedarian genome-wide characteristics and phylogenetic relationships analyses were carried out based on next-generation sequencing (NGS) platform. The revised genome size was approximately 1 310 Mb, with the largest scaffold length reaching 23 878 bp through K-mer (K = 17) method. The heterozygosity, repetitive rate and average GC content were about 0.94%, 51.93% and 42.23%, respectively. A total of 1 160 104 microsatellite motifs were identified from the de novo assembled genome of D. anguillare, in which dinucleotide repeats accounted for the largest proportion (592 234, 51.05%), the highest occurrence frequency (14.58%) as well as the largest relative abundance (379.27/Mb). The high-polymorphic and moderate-polymorphic loci composed around 73% of the total single sequence repeats (SSRs), showing a latent capacity for subsequent population genetic structure and genetic diversity appraisal researches. Another byproduct of whole-genome sequencing, the double-stranded and circular mitogenome (16 690 bp) was assembled to investigate the evolutionary relationships of D. anguillare. The phylogenic tree constructed with maximum likelihood (ML) method showed that D. anguillare was closely related to Synaphobranchidae species, and the molecular systematic results further supported classical taxonomy status of D. anguillare.

Levels and patterns of genetic variation in Japanese whiting (Sillago japonica) based on mitochondrial DNA control region.

Japanese whiting (Sillago japonica) is a commercially important demersal fish distributed along the coasts of East Asia and becomes recently an aquaculture species. Despite its commercial importance, the levels and patterns of population genetic variation remain poorly understood. In this study, 346 specimens were collected from 14 localities along the coastal waters of China, Korea and Japan and their genetic variation was analyzed with mtDNA control region (D-loop) sequences. A total of 131 polymorphic sites were detected which determined 294 haplotypes. A pattern with high levels of haplotype diversity (h = 0.999 ± 0.001) and nucleotide diversity (л = 0.030 ± 0.015) was detected in the examined range. Analyses of analysis of molecular variance (AMOVA) and Fst showed that no significant genetic differentiation existed among China, Korea and Japan populations, excepting for the populations between Ise Bay (IBP) sample and the other ones. Minimum spanning tree (MST), neutrality tests, mismatch distribution and Bayesian skyline analyses indicated that the species along coastline of China, Korea and Japan have experienced population expansions originated in its most recent history at about 106-423 kya during the late Pleistocene glaciations and deglaciations periods.

Fluorous Solid-Phase Extraction Assisted New Methods for Analysis of Biomolecules with Mass Spectrometry / 分析化学

Fluorous solid-phase extraction ( FSPE ) is a solid-phase extraction technique based on fluorous affinity between perfluorous compounds. It requires derivatization on analytes with fluorous tags and further specific separation accomplished by perfluorinated solid phase. This technique has extended to various research fields with broad application including organic synthesize, catalysis, chemical and biological analysis. Recently, owing to its good compatibility with mass spectrometry, new analytic techniques relying on FSPE coupled to biological mass spectrometry have received wide attention. This review briefly introduced the principle of FSPE and emphasized on its application for the analysis of biomolecules with mass spectrometry, as well as its outlook of future development.