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971.

Background  

The midgut undergoes histolysis and remodeling during the larval to adult transition in holometabolous insects, but the molecular mechanisms underlying this process are not well understood.  相似文献   
972.
973.
In Drosophila, Black cells (Bc) encodes a Prophenoloxidase and is expressed late in the maturation of crystal cells, which are blood cells involved in wound healing and immune encapsulation. Enhancer analysis of Bc revealed a 1,025-bp upstream sequence that regulates gene expression in a crystal cell exclusive pattern. Expression of this fragment is altered by mutations in the GATA family serpent (srp) and RUNX family lozenge (lz) genes; Srp and Lz are required for crystal cell specification. Deletional analysis uncovered a 330-bp crystal cell-specific sequence, which contains two GATA and three Lz binding sites. Mutational analysis revealed that both GATA sites are necessary, but not sufficient for crystal cell expression. However, one of the Lz sites is essential for crystal cell expression. Thus, Srp and Lz do not just specify the crystal cell lineage, but also regulate the later differentiation of these cells. Additionally, we now have a sensitive tool for marking crystal cells in live animals.  相似文献   
974.
Jiang  Peiqiang  Ren  Xintao  Wang  Wenjing  Niu  Guojiang  Li  Jing 《Antonie van Leeuwenhoek》2022,115(5):635-644

A Gram-staining-positive, non-spore-forming, non-flagellated, ellipsoidal, strain Z1-20 T belonging to the genus Arthrobacter was isolated from a soil sample collected from the Zhongshan station, Antarctic. Phylogenetic analysis of the 16S rRNA gene sequences and phylogenetic analysis revealed that strain Z1-20 T formed a unique single cluster in the genus Arthrobacter and shared high 16S rRNA sequence similarities of 97.1% and 96.9% with A. glacialis HLT2-12-2 T and A. psychrochitiniphilus GP3T, respectively. Values of Digital DNA-DNA hybridization (dDDH) between strain Z1-20 T against A. glacialis HLT2-12-2 T and A. psychrochitiniphilus GP3T were 20.3% and 13.8%, respectively. Average nucleotide identity (ANI) score between strain Z1-20 T against A. glacialis HLT2-12-2 T and A. psychrochitiniphilus GP3T were 72.5% and 72.1%, respectively. Genes for the synthesis of the osmoprotectant glycine betaine and higher copies of capA gene encoding cold shock protein were found in genome of Z1-20 T that may help Z1-20 T in cold-adaptation. Strain Z1-20 T comprised lysine as the diagnostic diamino acid. Based on the results of phylogenetic, phenotypic and chemotaxonomic features, strain Z1-20 T represents a novel species of a novel taxon of genus Arthrobacter, for which the name Arthrobacter terrae gen. nov., sp. nov. is proposed.

  相似文献   
975.
Zhang  Jianmin  Zha  Wenzhang  Qian  Changchun  Ding  Aixing  Mao  Zhongqi 《Biochemical genetics》2022,60(2):558-575
Biochemical Genetics - Resistance to cisplatin (CDDP) remains a major challenge for the treatment of gastric cancer (GC). Circular RNAs (circRNAs) have been implicated in the development of CDDP...  相似文献   
976.
Compatible solutes are key for the ability of halophilic bacteria to resist high osmotic stress. They have received wide attention from researchers for their excellent osmotic protection properties. Hydroxyectoine is a particularly important compatible solute, but its production by microbes faces several challenges, including low titer/yield, the presence of the byproduct ectoine, and the requirement of high salinity. Here, we aimed to metabolically engineer Escherichia coli to efficiently produce hydroxyectoine in the absence of osmotic stress without accumulating the byproduct ectoine. First, combinatorial optimization of the expression strength of key genes in the ectoine synthesis module and hydroxyectoine synthesis module was conducted. After optimization of the expression of these genes, 12.12 g/L hydroxyectoine and 0.24 g/L ectoine were obtained at 36 h in shake-flask fermentation with the addition of the co-substrate α-ketoglutarate. Further optimization of the addition of α-ketoglutarate achieved the sole production of hydroxyectoine (i.e., no ectoine accumulation), indicating that the supply of α-ketoglutarate is critically important for sole hydroxyectoine production. Finally, quorum sensing-based auto-regulation of intracellular α-ketoglutarate pool was implemented as an alternative to α-ketoglutarate addition by coupling the expression of sucA with the esaI/esaR circuit, which led to 14.93 g/L hydroxyectoine with a unit cell yield of 1.678 g/g and no ectoine accumulation in the absence of osmotic stress. This is the highest reported titer of sole hydroxyectoine production under salinity-free fermentation to date.  相似文献   
977.
Soil degradation threatens the forest sustainable productivity, particularly in afforestation system. Biochar derived from agroforestry waste or biomass can potentially improve the degraded forest soil and promote the tree growth. To expand the application of biochar for forestry productivity improvement, we here reviewed the effects and the underlying mechanisms of biochar on the degraded forest soil and tree growth. Totally 96 studies that conducted from pot to field investigations in China were summarized. The result suggested that biochar generally exerted positive effects on restoration of degraded forest soil such as that with compaction, acidification or soil erosion, which are mainly manifested by improving soil porosity, increasing pH, enhancing erosion resistance and mitigating greenhouse gas emissions. Furthermore, biochar incorporation promoted the growth of tested trees in most cases, which effect was mainly attributing to directly supplying nutrients, improving soil physio-chemical properties, enhancing the root’s nutrient absorption capacity, and enlarging the living space. In summary, current studies demonstrate that biochar has a unique potential for improving degraded forest soils and promoting tree growth. However, investigations on the underlying mechanisms and the long-term effects should be strengthened.  相似文献   
978.
Kernel size-related traits, including kernel length, kernel width, and kernel thickness, are critical components in determining yield and kernel quality in maize (Zea mays L.). Dissecting the phenotypic characteristics of these traits, and discovering the candidate chromosomal regions for these traits, are of potential importance for maize yield and quality improvement. In this study, a total of 139 F2:3 family lines derived from EHel and B73, a distinct line with extremely low ear height (EHel), was used for phenotyping and QTL mapping of three kernel size-related traits, including 10-kernel length (KL), 10-kernel width (KWid), and 10-kernel thickness (KT). The results showed that only one QTL for KWid, i.e., qKWid9 on Chr9, with a phenotypic variation explained (PVE) of 13.4% was detected between SNPs of AX-86298371 and AX-86298372, while no QTLs were detected for KL and KT across all 10 chromosomes. Four bulked groups of family lines, i.e., Groups I to IV, were constructed with F2:3 family lines according to the phenotypic comparisons of KWid between EHel and B73. Among these four groups, Group I possessed a significantly lower KWid than EHel (P =0.0455), Group II was similar to EHel (P =0.34), while both Group III and Group IV were statistically higher than EHel (P <0.05). Besides, except Group IV exhibited a similar KWid to B73 (P =0.11), KWid of Groups I to III were statistically lower than B73 (P <0.00). By comparing the bulked genotypes of the four groups to EHel and B73, a stable chromosomal region on Chr9 between SNPs of AX-86298372 to AX-86263154, entirely covered by qKWid9, was identified to link KWid with the positive allele of increasing phenotypic effect to KWid from B73, similar to that of qKWid9. A large amount of enzyme activity and macromolecule binding-related genes were annotated within this chromosomal region, suggesting qKWid9 as a potential QTL for KWid in maize.  相似文献   
979.
Niu  Baolin  Lei  Xiaohong  Xu  Qingling  Ju  Yi  Xu  Dongke  Mao  Liya  Li  Jing  Zheng  Yufan  Sun  Ning  Zhang  Xin  Mao  Yimin  Li  Xiaobo 《Cell biology and toxicology》2022,38(3):505-530
Cell Biology and Toxicology - Acetaminophen (APAP) overdose is a common cause of drug-induced liver injury (DILI). Ferroptosis has been recently implicated in APAP-induced liver injury (AILI)....  相似文献   
980.
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