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Zhang, Q.-J.

Publications and source records attributed to Zhang, Q.-J..

5 recordsLinked to original sources

The Multifaceted Effects of Short-Term Acute Hypoxia Stress: Insights into the tolerance mechanism of Propsilocerus akamusi (Diptera: Chironomidae)

Plenty of freshwater species, especially macroinvertebrates that are essential to the provision of numerous ecosystem functions, encountered higher mortality due to acute hypoxia. However, within the family Chironomidae, a wide range of tolerance to hypoxia/anoxia is displayed and Propsilocerus akamusi depends on this great endurance to become a dominant species in eutrophic lakes. To further understand how P. akamusi responds to acute hypoxic stress, we used multi-omics analysis in combination with histomorphological characteristics and physiological indicators. To evaluate enzyme activity, the transcriptome and metabolome, and histomorphological characteristics, we set up two groups: a control group (DO 8.4mg/L) and a hypoxic group (DO 0.39mg/L). With blue-black chromatin, cell tightness, cell membrane invagination, and the production of apoptotic vesicles, tissue cells displayed typical apoptotic features. While lactate dehydrogenase (LDH), (Alcohol dehydrogenase) ADH, catalase (CAT), and Na+/K+ -ATPase (NKA) activities were dramatically enhanced under hypoxic stress, glycogen content, and superoxide dismutase (SOD) activities were significantly reduced compared to the control group. The above results were further supported by the joint analysis of the transcriptome and metabolome, which further revealed that in addition to carbohydrates, including glycogen, the energy metabolism of the fatty acid, trehalose, and glyoxylate cycles is also included. Furthermore, we also revealed the ethanol tested in hypoxic stress should derive from symbiodinium of P akamusi. Understanding the processes which enable P. akamusi to survive lengthy periods of hypoxia in eutrophic lakes might help to design sensitive biomonitoring procedures, and this species has the potential to be used as an effective eutrophication indicator.

biophysics↗

Hepatic FGF21 mediates tissue tolerance during bacterial inflammation by preserving cardiac function

Sickness behaviors, including anorexia, are evolutionarily conserved responses to acute infections. Inflammation-induced anorexia causes dramatic metabolic changes, of which components critical to survival are unique depending on the type of inflammation. Glucose supplementation during the anorectic period induced by bacterial inflammation suppresses adaptive fasting metabolic pathways, including fibroblast growth factor-21 (FGF21), and decreases survival. Consistent with this observation, FGF21 deficient mice are more susceptible to mortality from endotoxemia and poly-bacterial peritonitis, but not viral infection. Here we report that increased circulating FGF21 during bacterial inflammation is hepatic-derived, promotes cardiac function, and is required for survival. FGF21 signaling downstream of its obligate co-receptor beta-Klotho (KLB) is required. However, mice with central nervous system or adipose-specific deletion of Klb do not demonstrate any difference in response to bacterial inflammation, suggesting that multiple tissues and/or a novel FGF21 target tissue are required for the full protective effect of FGF21. These data suggest that hepatic FGF21 is a novel cardioprotective factor in bacterial sepsis. eTOC SummaryIn response to bacterial inflammation, hepatic fibroblast growth factor 21 (FGF21), an endocrine hormone that mediates adaptive responses to metabolic stresses such as starvation, promotes survival by supporting heart function.

immunology↗

SMRT sequencing generates the chromosome-scale reference genome of tropical fruit mango, Mangifera indica

Mango (Mangifera indica), a member of the family Anacardiaceae, is one of the worlds most popular tropical fruits. Here we sequenced the variety, "Hong Xiang Ya", and generated a 371.6-Mb mango genome assembly with 34,529 predicted protein-coding genes. Aided with the published genetic map, for the first time, we assembled the M. indica genome to the chromosomes, and finally about 98.77% of the genome assembly was anchored to 20 pseudo-chromosomes. The availability of the chromosome-length genome assembly of M. indica will provide novel insights into genome evolution, understand the genetic basis of specialized phytochemical composites relevant to fruit quality, and enhance allele mining in genomics-assisted breeding for mango genetic improvement.

genomics↗

SMRT sequencing of the Oryza rufipogon genome reveals the genomic basis of rice adaptation

Asian cultivated rice is believed to have been domesticated from an immediate ancestral progenitor, Oryza rufipogon, which provides promising sources of novel alleles for world rice improvement. Here we first present a high-quality de novo assembly of the typical O. rufipogon genome through the integration of single-molecule sequencing (SMRT), 10x and Hi-C technologies. This chromosome-based reference genome allows a multi-species comparative analysis of the annual selfing O. sativa and its two wild progenitors, the annual selfing O. nivara and perennial outcrossing O. rufipogon, identifying massive numbers of dispensable genes that are functionally enriched in reproductive process. Comparative genomic analyses identified millions of genomic variants, of which large-effect mutations (e.g., SVs, CNV and PAVs) may affect the variation of agronomically significant traits. We demonstrate how lineage-specific expansion of rice gene families may have contributed to the formation of reproduction isolation (e.g., the recognition of pollen and male sterility), thus brightening the role in driving mating system evolution during the evolutionary process of recent speciation. We document thousands of positively selected genes that are mainly involved in flower development, ripening, pollination, reproduction and response to biotic- and abiotic stresses. We show that selection pressures may serve as crucial forces to govern substantial genomic alterations among the three rice species that form the genetic basis of rapid evolution of mating and reproductive systems under diverse habitats. This first chromosome-based wild rice genome in the genus Oryza will become powerful to accelerate the exploration of untapped genomic diversity from wild rice for the enhancement of elite rice cultivars.

genomics↗

Rapid and recent evolution of LTR retrotransposons drives rice genome evolution during the speciation of AA- genome Oryza species

The dynamics of LTR retrotransposons and their contribution to genome evolution during plant speciation have remained largely unanswered. Here, we perform a genome-wide comparison of all eight Oryza AA- genome species, and identify 3,911 intact LTR retrotransposons classified into 790 families. The top 44 most abundant LTR retrotransposon families show patterns of rapid and distinct diversification since the species split over the last ~4.8 Myr. Phylogenetic and read depth analyses of 11 representative retrotransposon families further provide a comprehensive evolutionary landscape of these changes. Compared with Ty1-copia, independent bursts of Ty3-gypsy retrotransposon expansions have occurred with the three largest showing signatures of lineage-specific evolution. The estimated insertion times of 2,213 complete retrotransposons from the top 23 most abundant families reveal divergent life-histories marked by speedy accumulation, decline and extinction that differed radically between species. We hypothesize that this rapid evolution of LTR retrotransposons not only divergently shaped the architecture of rice genomes but also contributed to the process of speciation and diversification of rice.

evolutionary biology↗