Tektin bundle interacting protein, TEKTIP1, functions to stabilize the tektin bundle and axoneme in mouse sperm flagella.

Tektins are microtubule inner proteins (MIPs) and localize at the inside lumen of doublet microtubules (DMTs) of cilia/flagella. TEKTIP1, a newly identified protein by cryo-electron microscopy (cryo-EM), is proposed to be localized at the center of the tektin bundle and hypothesized to recruit tektins or stabilize the bundle. However, the physiological role of TEKTIP1 is unknown. In this study, we generated Tektip1-knockout (Tektip1-/-) mice and showed that they were male subfertile primarily due to reduced sperm motility. A high percentage of sperm from Tektip1-/- mice showed moderately disorganized axoneme structures and abnormal flagellar waveforms. TEKTIP1 predominately interacted with TEKT3 among tektins. Loss of TEKTIP1 partially disturbed the organization of tektin bundle by mainly affecting the native status of TEKT3 and its interaction with other tektins. Collectively, our study reveals the physiological role and potential molecular mechanism of TEKTIP1 in axonemal structure and sperm motility, highlights the importance of MIPs in stabilizing DMTs, and suggests a potential relevance of TEKTIP1 deficiency to human asthenospermia. Tektip1-/- mice will be an excellent animal model to study the DMT organization of sperm flagella using cryo-EM in future.

Diffusion-relaxation correlation spectrum imaging for predicting tumor consistency and gross total resection in patients with pituitary adenomas: a preliminary study.

OBJECTIVE: To evaluate the ability of diffusion-relaxation correlation spectrum imaging (DR-CSI) to predict the consistency and extent of resection (EOR) of pituitary adenomas (PAs). METHODS: Forty-four patients with PAs were prospectively enrolled. Tumor consistency was evaluated at surgery as either soft or hard, followed by histological assessment. In vivo DR-CSI was performed and spectra were segmented following to a peak-based strategy into four compartments, designated A (low ADC), B (mediate ADC, short T2), C (mediate ADC, long T2), and D (high ADC). The corresponding volume fractions ([Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text]) along with the ADC and T2 values were calculated and assessed using univariable analysis for discrimination between hard and soft PAs. Predictors of EOR > 95% were analyzed using logistic regression model and receiver-operating-characteristic analysis. RESULTS: Tumor consistency was classified as soft (n = 28) or hard (n = 16). Hard PAs presented higher [Formula: see text] (p = 0.001) and lower [Formula: see text] (p = 0.013) than soft PAs, while no significant difference was found in other parameters. [Formula: see text] significantly correlated with the level of collagen content (r = 0.448, p = 0.002). Knosp grade (odds ratio [OR], 0.299; 95% confidence interval [CI], 0.124-0.716; p = 0.007) and [Formula: see text] (OR, 0.834, per 1% increase; 95% CI, 0.731-0.951; p = 0.007) were independently associated with EOR > 95%. A prediction model based on these variables yielded an AUC of 0.934 (sensitivity, 90.9%; specificity, 90.9%), outperforming the Knosp grade alone (AUC, 0.785; p < 0.05). CONCLUSION: DR-CSI may serve as a promising tool to predict the consistency and EOR of PAs. CLINICAL RELEVANCE STATEMENT: DR-CSI provides an imaging dimension for characterizing tissue microstructure of PAs and may serve as a promising tool to predict the tumor consistency and extent of resection in patients with PAs. KEY POINTS: • DR-CSI provides an imaging dimension for characterizing tissue microstructure of PAs by visualizing the volume fraction and corresponding spatial distribution of four compartments ([Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text]). • [Formula: see text] correlated with the level of collagen content and may be the best DR-CSI parameter for discrimination between hard and soft PAs. • The combination of Knosp grade and [Formula: see text] achieved an AUC of 0.934 for predicting the total or near-total resection, outperforming the Knosp grade alone (AUC, 0.785).

Product-State Distributions of Three-Body Recombination in Zero-Collision-Energy 4He2-Alkaline-Earth-Metal Systems.

The distributions of product states after three-body recombination (TBR) of zero-collision-energy 4He2X systems, with X being 9Be, 24Mg, 40Ca, 88Sr, or 138Ba, are investigated in the hyperspherical representation by quantum mechanically solving the Schrödinger equation. It is found that the weakly bound (dimer) product states are preferentially populated for all of these cases, which could be understood from the joint effects of the lowest incident channel and the relatively long-range behavior of the corresponding nonadiabatic couplings among these lowest incident and shallow recombination channels. For the strongly bound products, since the flow is accessible in the small hyperradial region, their distributions are closely related to the behavior of the nonadiabatic couplings among the corresponding deep recombination channels. Particularly, our results indicate that the products are not always formed exclusively in the most weakly bound state when the scattering lengths among the reactants are relatively large and that there may exist a large fluctuation of the strongly bound products versus their binding energies in the universal region. In addition, the total TBR rates of these nonuniversal systems are also accounted for by the joint effects of the main adiabatic potentials and nonadiabatic couplings.

Full-dimensional quantum mechanical study of three-body recombination for cold 4He-4He-20Ne system.

The increase of the number of the two-body recombination channels strongly challenges the numerical calculation of the accurate rates for the three-body recombination (TBR) process and its reverse process, collision-induced dissociation (CID), at ultracold temperatures. By taking the 4He-4He-20Ne collision system as an example, we have obtained the rates for its TBR and CID processes involving all four recombination channels, including the two-body states 4He2 (l = 0) and 4He20Ne (l = 0, 1, 2) with l the rotational quantum number. By using the adiabatic hyperspherical method, we have considered not only total angular momentum J = 0 but also J > 0 in the ultracold collision energies (E = 0.01 - 100 mK × kB). It is found that 4He2 (l = 0) is the major product after the TBR process in the ultracold limit (E ≤ 0.1 mK × kB). The TBR rate into 4He2 (l = 0) is nearly one order of magnitude larger than the sum of the other three products, 4He20Ne (l = 0, 1, 2). Moreover, the CID rates for the three 4He20Ne (l = 0, 1, 2) + 4He initial states are close to each other and are smaller than that for the 4He2 (l = 0) + 20Ne initial state. Additionally, we have, for the first time, performed the channel-resolved scattering calculation that can explain the above-mentioned findings quantitatively.

Ultracold state-to-state chemistry for three-body recombination in realistic 3He2-alkaline-earth-metal systems.

The ultracold state-to-state chemistry for three-body recombination (TBR) in realistic systems has recently been experimentally investigated with full quantum state resolution. However, many detected phenomena remain challenging to be explored and explained from the theoretical viewpoints because this generally requires computational powers beyond state of the art. Here, the product-state distributions after TBR of 3He2-alkaline-earth-metal systems, i.e., after the processes of 3He + 3He + X → 3HeX + 3He with X being 9Be, 24Mg, 40Ca, 88Sr, or 138Ba, in the zero-collision-energy limit are theoretically studied. Two propensity rules for the distribution of the products found in current experiments have been checked, and the mechanism underlying these product-state distributions is explored. Particularly, two main intriguing transition pathways are identified, which may be responsible for the nonlinear distribution of the products vs their respective rotational quantum number. In addition, the TBR rates of these systems are also influenced by details of the interaction potential and relevant nonadiabatic couplings.

Scattering length scaling rules for atom-atom-anion three-body recombination of zero-energy 4He4He6Li- system.

The scattering length scaling rules for three-body recombination (TBR) of the 4He4He6Li- system in the zero-energy limit (E → 0) are investigated by considering various post-Born-Oppenheimer (post-BO) contributions to the standard BO potential of He-He interaction. It is found that these post-BO effects on the TBR rates that lead to different dimer products could be well fitted by the scattering length scalings Cab with a being the scattering length of the He-He interaction, and b and C the constants. It is interesting to find that the powers b about both the weakly and deeply bound dimer products are quite different from the well-known powers given by the scattering length scaling laws in the fields of ultracold neutral atomic gases. Such difference and the distinct powers associated with various dimer products are qualitatively accounted for by the properties of the major effective potentials and relatively long-range nonadiabatic couplings. Particularly, from these properties, the scaling powers are expected to be dependent on systems, but the power scattering length scaling behaviors to be universal, which has also been checked to apply to a wide range of a by tuning the He-He interaction.

Relationship between the laminectomy extension and spinal cord injury caused by acute spinal shortening: goat in vivo experiment.

OBJECTIVE: To investigate the relationship between different types of laminectomy extension and spinal cord injury subsequent to acute spinal shorting after 3-column osteotomy in living goat model. METHODS: A total of 18 healthy goats were selected, and a procedure of bivertebral column resections and total laminectomy of T13 and L1 was completed followed by different laminectomy extensions under the somatosensory evoked potential (SSEP) monitoring. The samples were divided into three groups according to types of subsequent laminectomy extension. In the first group (enlarged resection of upper lamina group), laminectomy extension was performed on 10 mm caudal to T12; in the second group (equidistant enlarged resection of upper and lower lamina group), laminectomy extension was performed on 5 mm caudal to T12 and 5 mm cranial to L2 simultaneously; and in the third group (enlarged resection of lower lamina group), laminectomy extension was performed on 10 mm cranial to L2. The SSEP measured after vertebral resection was set as the baseline, and the SSEP decreased by 50% from the baseline amplitude and/or delayed by 10% relative to the baseline peak latency was set as positive results, which indicated spinal cord injury. Spinal column was gradually shortened until the SSEP monitoring just did not show a positive result. The shortened distance (ΔH) and the changed angle of the spinal cord buckling (Δα) were measured in each group. Neurologic function was recorded by the Tarlov scores at 2 days after the surgery. RESULTS: The safe shortening distances of three groups were 38.6 ± 1.2 mm, 41.5 ± 0.7 mm, 43.7 ± 0.8 mm, respectively; the corresponding changed angles of the spinal cord buckling were 62.8 ± 6.9°, 82.8 ± 7.5°, and 98.5 ± 7.0°. Significant differences of ΔH and Δα were found among the three groups by LSD multiple comparison test (P < 0.05). Strong correlation between ΔH and Δα was shown in each group by Pearson's correlation test. CONCLUSIONS: Different laminectomy extensions after 3-column osteotomy have different effects on the prevention of SCI caused by acute spinal shortening. The enlarged resection of lower lamina is superior to equidistant enlarged resection of upper and lower laminas which is superior to enlarged resection of upper lamina in preventing SCI. These slides can be retrieved under Electronic Supplementary Material.

Cold atom-atom-anion three-body recombination of 4He4HexLi- (x = 6 or 7) systems.

Atom-atom-anion three-body recombination (TBR) in mixed 4He and xLi- (x = 6 or 7) is investigated in the adiabatic hyperspherical representation by quantum mechanically solving the Schrödinger equation. The distributions of product states following these TBR processes are found to be relatively different for the two systems when the collision energy is less than roughly 0.6 mK × kB or 0.3 mK × kB for 4He4He6Li- and 4He4He7Li- systems, respectively, with kB being the Boltzmann constant. For 4He4He6Li- systems, the rate of recombination into (v=0) l = 04He6Li- molecular anions is the largest with v and l denoting the rovibrational quantum numbers, while the TBR rate that leads to the formation of l = 14He6Li- molecular anions is a little smaller than that of neutral 4He2 molecules. For 4He4He7Li- systems, neutral 4He2 molecules tend to be the most products, following the yields of l = 0 and 1 4He7Li- molecular anions. However, in spite of these distinctly different distributions, the products of molecular anions, the sum of l = 0 and 1 4HexLi- products, are relatively larger than that of neutral 4He2 molecules for both the two systems.

Evidence for kinesio taping in management of myofascial pain syndrome: a systematic review and meta-analysis.

OBJECTIVE: The aim of this study was to evaluate the effectiveness of kinesio taping for managing myofascial pain syndrome in terms of pain intensity, pressure pain threshold, range of motion, muscle strength and disability. DATA SOURCES: PubMed, EBSCO, ScienceDirect, Web of Science, Cochrane Library and Physiotherapy Evidence Databases were searched from database inception to November 2018. METHODS: Randomized controlled trials (RCTs) that used kinesio taping as the main treatment protocol for participants diagnosed with myofascial pain syndrome were included. Two reviewers independently screened articles, scored methodological quality using Cochrane risk-of-bias tool and extracted data. The primary outcomes were pain intensity, pressure pain threshold and range of motion at post-intervention and follow-up. The secondary outcomes were muscle strength and disability at post-intervention and follow-up. DATA SYNTHESIS: Meta-analyses of 20 RCTs involving 959 patients showed that kinesio taping was more effective than other treatments in reducing pain intensity (mean difference (MD) = 1.06 cm, 95% confidence interval (CI): -1.66 to -0.46 cm, P = 0.006) and increasing range of motion (standardized mean difference (SMD) = 0.26, 95% CI: 0.09 to 0.43, P = 0.003) at post-intervention. Kinesio taping was also superior to other non-invasive techniques in relieving pain intensity at follow-up (MD = -0.68 cm, 95% CI: -1.22 to -0.13 cm, P = 0.02). However, there was no detectable effect on disability or function. CONCLUSION: Statistical evidence showed that kinesio taping could be recommended to relieve pain intensity and range of motion for patients with myofascial pain syndrome at post-intervention.

Imaging of guided waves using an all-fiber reflection-based NSOM with self-compensation of a phase drift.

A phase-resolved reflection-based near-field scanning optical microscopy (NSOM) technique with an original all-fiber configuration is presented. Our system consists of an intrinsically phase-stable common-path interferometer. The reflection from the waveguide input facet or from an integrated fiber Bragg grating is used as the reference beam. This arrangement effectively suppresses the phase drift caused by environmental fluctuations. By raster scanning a silicon atomic force microscope probe, we measure the complex near fields of the propagating and stationary waves in silicon nanowaveguides. Our robust, align-free, cost-effective, and shot-noise-limited near-field imaging technique paves the way for versatile optical characterizations of nanophotonic structures on a chip.

An Experimental Study on the Optimal Timing for the Repair of Incomplete Facial Paralysis by Hypoglossal-facial 'Side'-to-side Neurorrhaphy in Rats.

OBJECTIVE: To investigate the optimal timing for the repair of persistent incomplete facial paralysis by hypoglossal-facial 'side'-to-side neurorrhaphy in rats. METHODS: A total of 30 adult rats with crushed and bulldog-clamped facial nerve injury were randomly divided into 5 groups (n = 6 each) that were subjected to injury without nerve repair or with immediate repair, 2-week-delayed repair, 4-week-delayed repair, or 8-week-delayed repair. Three months later, the effects of repair in each rat were evaluated by facial symmetry assessment, electrophysiological examination, retrograde labeling, and axon regeneration measurement. RESULTS: At 3 months after injury, the alpha angle significantly increased in the group of rats with 4-week-delayed repair compared with the other four groups. Upon stimulation of the facial nerve or Pre degenerated nerve, the muscle action potentials MAPs were recorded in the whisker pad muscle, and the MAP amplitude and area under the curve in the 4-week-delayed repair group were significantly augmented at 3 months post-injury. Similarly, the number of retrograde-labeled motor neurons in the facial and hypoglossal nuclei was quantified to be significantly greater in the 4-week-delayed repair group than in the other groups, and a large number of regenerated axons was also observed. CONCLUSION: The results of this study demonstrated that hemiHN-FN neurorrhaphy performed 4 weeks after facial nerve injury was most effective in terms of the functional recovery of axonal regeneration and activation of facial muscles.

[Advances in study of plant type â ¢ polyketide synthases].

Polyketides are a large class of natural products with notable structural diversity and different biological activities. They have essential pharmacological value for human health. In plants, the enzymes responsible for the formation of phenolic metabolites backbone structures are collectively known as type Ⅲ polyketide synthases (PKSs), which are the key enzymes for the polyketides biosynthesis. The PKSs catalyze a series of condensation reactions of two-carbon acetate units with an acyl starter. A brief overview of this group of enzymes, including their reaction mechanisms, function modification, expression regulation, molecular evolution, and recent interesting findings are presented here.

Cold atom-atom-ion three-body recombination of 4He-4He-X- (X = H or D).

The atom-atom-ion three-body recombination (TBR) of mixed 4He and X- (X = H or D) systems is investigated by solving the Schrödinger equation using the adiabatic hyperspherical representation method. It is shown that the dominant products after a TBR in the ultracold limit (E ≤ 0.1 mK × kB) are different for the two systems. For the 4He4HeH- system, the rate of TBR into the 4HeH- ion is nearly two orders of magnitude larger than that of TBR into the neutral 4He2 molecule. In contrast, the yield of 4He2 is a little higher than that of 4HeD- for the 4He4HeD- system. Furthermore, since the adiabatic potentials become more attractive and the nonadiabatic couplings become much stronger by substituting D for H in the 4He4HeH- system, the total TBR rate for the 4He4HeD- system is nearly two orders of magnitude larger than that for the 4He4HeH- system.

EXPRESSION AND EFFECTS OF MUTANT Bombyx mori ACETYLCHOLINESTRASE1 IN BmN CELLS.

The main mechanism of toxicity of organophosphate (OP) and carbamate (CB) insecticides is their irreversible binding and inhibition of acetylcholinestrase (AChE), encoded by ace1 (acetylcholinestrase gene 1), leading to eventual death of insects. Mutations in AChE may significantly reduce insects susceptibility to these pesticides. Bombyx mori is an important beneficial insect, and no OP- or CB-resistant strains have been generated. In this study, wild-type ace1 (wace1) and mutant ace1 (mace1) were introduced into BmN cells, confirmed by screening and identification. The expression of wace1 and mace1 in the cells was confirmed by Western blot and their expression levels were about 21-fold higher than the endogenous ace1 level. The activities of AChE in wace1 and mace1 transgenic cells were 10.6 and 20.2% higher compared to control cells, respectively. mace1 transgenic cells had higher remaining activity than wace1 transgenic cells under the treatment of physostigmine (a reversible cholinesterase inhibitor) and phoxim (an OP acaricide). The results showed that ace1 transgene can significantly improve ace1 expression, and ace1 mutation at a specific site can reduce the sensitivity to AChE inhibitors. Our study provides a new direction for the exploration of the relationship between AChE mutations and drug resistance.

Role of sharp avoided crossings in short hyper-radial range in recombination of the cold 4He3 system.

The role of sharp avoided crossings (SACs) in a short hyper-radial range R≤ 50 a.u. in the calculation of recombination for a cold 4He3 system is investigated in the adiabatic hyperspherical representation by "turning off and on" the relevant nonadiabatic couplings. The influence of SACs on the recombination is related with the channels of the system and with the scattering energy. For JΠ = 0+ symmetry, the two-body recombination channel has an attractive potential well, which makes radial wave functions of both two-body recombination channel and three-body continuum channels accessible in the short hyper-radial range where SACs are located. The SACs consequently play an important role in coupled-channel calculations and this is particularly the case for lower scattering energies. However, for excited nuclear orbital momenta, i.e., JΠ = 1-, 2+,…, 7- symmetries, the two-body recombination channel has a repulsive interaction and the radial wave functions are not accessible in the short hyper-radial range. Therefore, omission of SACs in the short range for these symmetries has no effect on the numerical results, which leads to great savings on hyper-radial grid points in the practical numerical calculations. Moreover, to make the nonadiabatic couplings among channels to be continuous in the hyper-radius, different methods associated with the application of consistent phase convention are discussed.

Glycosyltransferases: mechanisms and applications in natural product development.

Glycosylation reactions mainly catalyzed by glycosyltransferases (Gts) occur almost everywhere in the biosphere, and always play crucial roles in vital processes. In order to understand the full potential of Gts, the chemical and structural glycosylation mechanisms are systematically summarized in this review, including some new outlooks in inverting/retaining mechanisms and the overview of GT-C superfamily proteins as a novel Gt fold. Some special features of glycosylation and the evolutionary studies on Gts are also discussed to help us better understand the function and application potential of Gts. Natural product (NP) glycosylation and related Gts which play important roles in new drug development are emphasized in this paper. The recent advances in the glycosylation pattern (particularly the rare C- and S-glycosylation), reversibility, iterative catalysis and protein auxiliary of NP Gts are all summed up comprehensively. This review also presents the application of NP Gts and associated studies on synthetic biology, which may further broaden the mind and bring wider application prospects.

Molecular alignment effect on the photoassociation process via a pump-dump scheme.

The photoassociation processes via the pump-dump scheme for the heternuclear (Na + H → NaH) and the homonuclear (Na + Na → Na2) molecular systems are studied, respectively, using the time-dependent quantum wavepacket method. For both systems, the initial atom pair in the continuum of the ground electronic state (X(1)Σ(+)) is associated into the molecule in the bound states of the excited state (A(1)Σ(+)) by the pump pulse. Then driven by a time-delayed dumping pulse, the prepared excited-state molecule can be transferred to the bound states of the ground electronic state. It is found that the pump process can induce a superposition of the rovibrational levels |v, j〉 on the excited state, which can lead to the field-free alignment of the excited-state molecule. The molecular alignment can affect the dumping process by varying the effective coupling intensity between the two electronic states or by varying the population transfer pathways. As a result, the final population transferred to the bound states of the ground electronic state varies periodically with the delay time of the dumping pulse.

[Enhanced radiosensitivity of H22 ascitic tumor to 12C6+ ions radiation in ultra-filtration extract mixture from Astragalus mongholicus-treated mice].

This study was designed to investigate the impact of ultra-filtration extract mixture from Astragals mongholicus (UEMAM) o radiosensitivity of H22 ascitic tumor in mice to 12C6+ ions radiation. The H22 ascitic tumor model was established in mice by intraperitoneal injection of 0.2 mL H22 ascitic cells. The animals were subsequently divided into 4 groups randomly, treated with normal saline, UEMAM, heavy ion beam radiotherapy and UEMAM plus heavy ion beam radiotherapy, respectively. The body weights, abdomen circumference of the mice were measured and the mouse behavior was monitored every day; survival time was recorded to evaluate life extension effect; flow cytometry technique was used to detect H22 cell apoptosis and cell cycle; protein levels of p53, Bax, Bcl-2 and cleaved Caspase-3 were analyzed by Western blot; the single cell gel electrophoresis was used to detect the level of deoxyribonucleic acid damage (DNA damage). The results suggest that UEMAM significantly increased survival time, and decreased body weights and abdomen circumference over the saline control group. The treatment increased cell apoptosis, cycle arrest and DNA damage compared to the saline control group. UEMAM significantly enhanced the therapeutic effect of heavy ion beam radiation in survival time, and decreased body weights and abdomen circumference in the tumor-baring mice. The combination increased cell apoptosis, cycle arrest and DNA damage compared to the radiotherapy group. The results of Western blot suggest that the treatment significantly enhanced p53-induced apoptotic signals. The experiment discovered that UEMAM could improve radiosensitivity of H22 ascitic tumor through activation of p53-mediated apoptotic signal pathway.

Identification and characterization of six cytochrome P450 genes belonging to CYP4 and CYP6 gene families in the silkworm, Bombyx mori.

It was predicted that the genome of silkworm, Bombyx mori, has at least 79 P450 genes; however, P450 genes that are related to the catabolism of exogenous compounds were not reported. In this study we cloned two CYP4 (named CPY4M5 and CYP4M9) and four CYP6 (named CYP6AB5, CYP6AE9, CYP6AE22 and CYP6AU1) genes by using both bioinformatics and RT-PCR approaches. Sequence analysis showed that these genes contained conserved P450 gene sequence regions and one conserved intron. CYP4M5 and CYP4M9 genes were clustered together in a mode of "head-to-tail" possibly due to gene duplication. Blast analysis showed that these P450 genes shared significant similarity with CYP4 and CYP6 genes that are involved in the catabolism and detoxification of exogenous compounds in other insect species. RT-PCR results showed that these P450 genes were highly expressed in the midgut and fat body of B. mori. As the instar age increased, these P450 genes exhibit different expression patterns. When B. mori was exposed to 1.75 × 10(-5)% of cypermethrin, 3.5 × 10(-6)% of cypermethrin and 0.1% of rutin, expression of CYP6AB5 was increased by 2.3-fold, 2.2-fold and 1.9-fold, respectively. Exposure of B. mori to 0.1% quercetin does not change the expression of CYP6AB5. In contrast, expression of the other five P450 genes was inhibited after exposed to these compounds.

Functional study on the mutations in the silkworm (Bombyx mori) acetylcholinesterase type 1 gene (ace1) and its recombinant proteins.

The acetylcholinesterase of Lepidoptera insects is encoded by two genes, ace1 and ace2. The expression of the ace1 gene is significantly higher than that of the ace2 gene, and mutations in ace1 are one of the major reasons for pesticide resistance in insects. In order to investigate the effects of the mutations in ace1's characteristic sites on pesticide resistance, we generated mutations for three amino acids using site-directed mutagenesis, which were Ala(GCG)303Ser(TCG), Gly(GGA)329Ala(GCA) and Leu (TCT)554Ser(TTC). The Baculovirus expression system was used for the eukaryotic expression of the wild type ace1 (wace1) and the mutant ace1 (mace1). SDS-PAGE and Western blotting were used to detect the targeting proteins with expected sizeof about 76 kDa. The expression products were purified for the determination of AChE activity and the inhibitory effects of physostigmine and phoxim. We observed no significant differences in the overall activity of the wild type and mutant AChEs. However, with 10 min of physostigmine (10 µM) inhibition, the remaining activity of the wild type AChE was significantly lower than that of the mutant AChE. Ten min inhibition with 33.4 µM phoxim also resulted in significantly lower remaining activity of the wild type AChE than that of the mutant AChE. These results indicated that mutations for the three amino acids reduced the sensitivity of AChE to physostigmine and phoxim, which laid the foundation for future in vivo studies on AChE's roles in pesticide resistance.