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991.
YanPing Wang EJiao Wu Yahuza Lurwanu JiPeng Ding DunChun He Abdul Waheed Oswald Nkurikiyimfura ShiTing Liu WenYang Li ZongHua Wang Lina Yang Jiasui Zhan 《Ecology and evolution》2021,11(10):5484
Genetic variation plays a fundamental role in pathogen''s adaptation to environmental stresses. Pathogens with low genetic variation tend to survive and proliferate more poorly due to their lack of genotypic/phenotypic polymorphisms in responding to fluctuating environments. Evolutionary theory hypothesizes that the adaptive disadvantage of genes with low genomic variation can be compensated for structural diversity of proteins through post‐translation modification (PTM) but this theory is rarely tested experimentally and its implication to sustainable disease management is hardly discussed. In this study, we analyzed nucleotide characteristics of eukaryotic translation elongation factor‐1α (eEF‐lα) gene from 165 Phytophthora infestans isolates and the physical and chemical properties of its derived proteins. We found a low sequence variation of eEF‐lα protein, possibly attributable to purifying selection and a lack of intra‐genic recombination rather than reduced mutation. In the only two isoforms detected by the study, the major one accounted for >95% of the pathogen collection and displayed a significantly higher fitness than the minor one. High lysine representation enhances the opportunity of the eEF‐1α protein to be methylated and the absence of disulfide bonds is consistent with the structural prediction showing that many disordered regions are existed in the protein. Methylation, structural disordering, and possibly other PTMs ensure the ability of the protein to modify its functions during biological, cellular and biochemical processes, and compensate for its adaptive disadvantage caused by sequence conservation. Our results indicate that PTMs may function synergistically with nucleotide codes to regulate the adaptive landscape of eEF‐1α, possibly as well as other housekeeping genes, in P. infestans. Compensatory evolution between pre‐ and post‐translational phase in eEF‐1α could enable pathogens quickly adapting to disease management strategies while efficiently maintaining critical roles of the protein playing in biological, cellular, and biochemical activities. Implications of these results to sustainable plant disease management are discussed. 相似文献
992.
Xiaoyong Liu Zhaodi Yi Ming Gao Haojun Zhang Buqiang Wang Hongjun Gao Yi Wu Yuping Chen 《Asia-Pacific Journal of Blood Types and Genes》2021,5(1):48-52
The paper aims to analyze a rare blood sample in Ganzhou City Hospital with CisAB subtype and explore a feasible pattern for blood typing of rare blood type patients, so as to ensure clinical transfusion safety. The routine serological methods were used for ABO forward and reverse blood typing and the fluorescence real-time PCR technique was used for sample genotyping. A human ABO blood group 6-7 exon sequencing kit was used for sequence analysis. The nucleic acid sequence of the sample was compared with reference sequences. The forward typing results demonstrated that the sample was ABw, RhD positive. The sample exhibited 4+ agglutination with anti-H and anti-AB antibodies. Reverse typing by microcolumn gel method showed an AB result, but the serum sample demonstrated weak agglutination with B cell under room temperature, 4 °C and 37 °C in saline when tested with tube method respectively. The serological results matched with the A2B3 serotype. The fluorescent real-time PCR genotyping results displayed A/O01. The sequence analysis demonstrated deletion of guanine in 261-position 467C>T (heterozygote) and 803G>T (heterozygote) mutation respectively. The mutation caused the A glycosyltransferase peptide chain to change from proline to leucine (P156L) at 156 and from glutamate to alanine (G268A) at 268. The result demonstrated that the sample''s genotype was CisAB01/O01. The mutation of glycosyltransferase coding gene leads to an abnormal serological reaction pattern. Only by combining the results of genetic analysis can we get the true sample blood type and better ensure the safety of clinical blood transfusion. 相似文献
993.
Xia Wu ∗ Yan Li ∗ Guang-Peng Li Dongshan Yang Yongli Yue Lingling Wang 《Animal biotechnology》2013,24(4):211-224
Reprogramming impairment of DNA methylation may be partly responsible for the low efficiency in somatic cell nuclear transfer. In this study, bovine fibroblast cells were transfected with enhancer green fluorescence protein (eGFP), and then treated with a histone-deacetylase inhibitor, trichostatin A (TSA). The results showed that the effect of TSA on transfected cells was dose dependent. When the TSA concentration was over 5 ng/ml, cell proliferation was significantly inhibited. The majority of the cells died when TSA reached 100 ng/ml (P < 0.01). The number of cells in the S phase was significantly decreased in the 5- to 50-ng/ml TSA-treated groups, while the majority of the cells were at the G0/G1 phases. The number of eGFP-expressed cells were approximately twofold higher in 25-ng/ml (30.5%) and 50-ng/ml (29.5%) TSA groups than the control (15.0%). Reduced DNA methylation and improved histone acetylation were observed when the cells were treated with 10 to 50 ng/ml of TSA. Transfer of the TSA-treated cells to enucleated recipient oocytes resulted in similar cleavage rates among the experimental groups and the control. Cells treated with 50 ng/ml of TSA resulted in significantly lower blastocyst development (9.9%) than the other experimental and the control groups (around 20%). Analysis of the putative blastocysts showed that 86.7% of the embryos derived from TSA-treated cells were eGFP positive, which was higher than that from untreated cells (68.8%). In conclusion, treatment of transfected cells with TSA decreased the genome DNA methylation level, increased histone acetylation, and eGFP gene expression was activated. Donor cells with reduced DNA methylation did not improve subsequent cloned embryo development; however, transgene expression was improved in cloned embryos. 相似文献
994.
Uncoupling proteins (UCPs) are mitochondrial membrane transporters, acting as an uncoupler in oxidative phosphorylation. In this study, we designed 11 primer sets based on the human and mouse UCP2, UCP3 sequences and successfully amplified full regions of porcine UCP2 and UCP3 by polymerase chain reactions (PCR). Comparison of the UCP2 and UCP3 genic structures revealed a highly conservative region was putatively presented, showing the second transmembrane domain may be the UCPs' cardinal function region. Altogether 23 nucleotide polymorphisms of UCP2 and UCP3 genes were discovered in Yorkshire, Wuzhishan, and Lepinghua pigs. These polymorphisms included 3 missense mutations, 16 intronic substitutions, and 4 intronic deletions. The substitution of Ala-55-Val in UCP2 is actually the most common mutation in human. We also calculated genotypic frequencies of five polymorphisms in three pig breeds. 相似文献
995.
996.
Ubiquitin-conjugating enzymes (UBE2s or E2s) are characterized by the presence of a highly conserved ubiquitin-conjugating (UBC) domain, which predominantly determines the type of ubiquitin chains and directly controls the cellular fate of the substrate. In this study, an E2 homolog was identified and functionally characterized in abalone, which we named ab-UBE2D. The full-length cDNA consists of 1005 bp with an ORF encoding a protein of 147 amino acids. The deduced amino acid sequence shows ab-UBE2D shares conserved UBC domain with other E2 proteins and belongs to class I E2 enzyme family, which are further confirmed by phylogenetic tree analysis. Real-time PCR and western blot analyses showed that ab-UBE2D was ubiquitously expressed in abalone and the expression level of ab-UBE2d was significantly induced by LPS and Poly (I:C). Immunofluorescence microscopy staining demonstrated that native ab-UBE2D was mainly distributed in the cytoplast. Ubiquitination assay showed that ab-UBE2D had ubiquitin conjugating activity to form the enzyme-(Ub)n conjugates. Taken together, these results strongly suggest that ab-UBE2D is an E2 homolog and it may be involved in the immune response of abalone, Haliotis diversicolor supertexta. 相似文献
997.
998.
Hua-Hua Du Chong-Lin Hou Xiao-Guo Wu Rong-hui Xie Yi-Zhen Wang 《Fish & shellfish immunology》2013,34(1):332-338
Previous studies identify VP28 envelope protein of white spot syndrome virus (WSSV) as its main antigenic protein. Although implicated in viral infectivity, its functional role remains unclear. In the current study, we described the production of polyclonal antibodies to recombinant truncated VP28 proteins including deleted N-terminal (rVP28ΔN), C-terminal (rVP28ΔC) and middle (rVP28ΔM). In antigenicity assays, antibodies developed from VP28 truncations lacking the N-terminal or middle regions showed significantly lowered neutralization of WSSV in crayfish, Procambarus clarkii. Further immunogenicity analysis showed reduced relative percent survival (RPS) in crayfish vaccinating with these truncations before challenge with WSSV. These results indicated that N-terminal (residues 1–27) and middle region (residues 35–95) were essential to maintain the neutralizing linear epitopes of VP28 and responsible in eliciting immune response. Thus, it is most likely that these regions are exposed on VP28, and will be useful for rational design of effective vaccines targeting VP28 of WSSV. 相似文献
999.
主要介绍了江苏濒危植物珊瑚菜的特征特性、生存现状.江苏沿海野生珊瑚菜种群被证实已灭绝,并探析了其灭绝的原因,为内在因素和外在因素的结合,但人为的外在因素对其生存的影响是致命性的.呼吁保护环境以拯救其它濒临灭绝的物种. 相似文献
1000.