灰霉菌MyosinⅠ的体外表达纯化及抑制剂筛选

[目的]本文旨在体外表达纯化灰霉菌Ⅰ型肌球蛋白(MyosinⅠ)及筛选抑制剂。[方法]采用SF9昆虫细胞蛋白表达系统表达灰霉菌MyosinⅠ(BcMyosinⅠ)马达结构域,用亲和层析和凝胶过滤层析纯化方法纯化蛋白,用SDS-PAGE和Western blot检测蛋白表达情况。从实验室已有的化合物库中,用ATPase活性试剂盒测定化合物对BcMyosinⅠ的酶活性抑制率。采用菌丝生长速率法测定部分化合物对灰霉菌的菌丝生长抑制活性。以禾谷镰刀菌Ⅰ型肌球蛋白(FgMyosinⅠ)三维结构为模板,同源模建预测BcMyosinⅠ三维结构。用AutoDock-Vina软件将部分化合物与BcMyosinⅠ进行分子对接。[结果]成功在体外表达纯化BcMyosinⅠ。20μmol·L^(-1)条件下,化合物B1和B17对BcMyosinⅠ的酶活性抑制率分别为56.24%和65.39%,显著高于对照药剂氰烯菌酯对酶活性的抑制率(27.29%);B1和B17对灰霉菌的菌丝生长抑制率分别为32.90%和83.44%,显著高于对照药剂氰烯菌酯对菌丝生长的抑制率(1.06%)。对照药剂氰烯菌酯与BcMyosinⅠ的结合自由能为-29.26 kJ·mol^(-1),而化合物B1和B17与BcMyosinⅠ的结合自由能分别为-35.53和-36.78 kJ·mol^(-1),结合自由能低,说明化合物B1和B17对BcMyosinⅠ的抑制活性均高于氰烯菌酯。[结论]成功获得BcMyosinⅠ单体蛋白;筛选出B1和B17两个灰霉菌肌球蛋白抑制剂。

Myosin-Vc特异性片段的原核表达及其抗血清的制备

目的原核表达Myosin-Vc(Myo5c)蛋白并纯化,制备小鼠、家兔多克隆抗体,为探索Myo5c在病毒感染中的作用提供研究工具。方法采用RT-PCR方法从人胃粘膜组织中克隆编码Myo5c特异性蛋白的基因片段,构建该片段与6×His标签的融合蛋白表达质粒pQE-31/Myo5c,原核表达与蛋白纯化后,分别免疫BALB/c小鼠和新西兰兔,制备Myo5c抗血清。采用ELISA检测抗体效价,Westernblot和间接免疫荧光染色检验抗体特异性。结果获得Myo5c特异性片段约42×103的纯化蛋白。ELISA检测小鼠和家兔抗血清效价分别为1∶12800、1∶6400。Westernblot和间接免疫荧光染色显示所制备的抗体能特异性识别Myo5c。结论获得Myo5c特异性蛋白,并成功地制备了Myo5c特异性的小鼠和家兔抗血清。

小鼠抗人Myosin Va多克隆抗体的制备和鉴定

目的:制备Myosin Va多克隆抗体,为深入研究其功能和探讨其与肿瘤等疾病的相关性提供工具。方法:PCR扩增编码人Myosin Va C末端(MyoVaCT)278个氨基酸的cD-NA片段,DNA重组入原核表达质粒pET28a,转化大肠杆菌BL21菌株,异丙基β-D硫代半糖苷(IPTG)诱导表达His-MyoVaCT融合蛋白。经电泳纯化的融合蛋白免疫BALB/c小鼠,制备抗血清。通过ELISA和免疫荧光法鉴定血清特异抗体效价和特异性。结果:成功构建了pET28a/MyoVaCT原核表达载体,转化BL21后可高效表达融合蛋白His-MyoVaCT,纯化蛋白免疫小鼠后产生的Myosin Va多抗可特异检测细胞内源性Myosin Va的表达及定位情况,同时能特异识别细胞内外源表达的Myosin Va分子。结论:获得了效价和特异性都良好的Myosin Va抗体,适合应用于Myosin Va的检测。

microRNA-146a通过靶向MAPK4和Myosin Va基因调控羊驼黑色素细胞增殖、迁移

旨在研究microRNA-146a(miR-146a)对羊驼黑色素细胞增殖和迁移的调控及其分子机制。本研究使用双荧光素酶试验验证MAPK4和Myosin Va是miR-146a的靶基因;利用荧光定量PCR和蛋白质免疫印迹试验检测在羊驼黑色素细胞中过表达miR-146a对相关下游基因表达的影响;利用CCK8和Transwell检测miR-146a过表达对羊驼黑色素细胞增殖和迁移的影响。结果显示,与对照组相比,将miR-146a和MAPK4或Myosin Va共转染293T细胞,双荧光素酶活性分别极显著下降36%和30%(P<0.001);MAPK4和Myosin Va基因转录水平分别极显著下调67%和47%(P<0.001,P<0.01);蛋白质水平的表达量分别显著或极显著下调38%和69%(P<0.05,P<0.01);增殖和迁移相关的基因CREB、MITF、MLPH和Rab27a在转录水平和蛋白水平的表达均极显著下调(P<0.01,P<0.001);CCK8和Transwell结果显示,过表达miR-146a使羊驼黑色素细胞的增殖和迁移能力极显著下调(P<0.01)。综上所述,miR-146a通过靶向调控MAPK4和Myosin Va,使增殖和迁移相关的基因MEK1、CREB、MITF、MLPH和Rab27a的表达下调,从而对羊驼黑色素细胞的增殖和迁移起抑制作用。

C57BL/6小鼠内耳前庭末梢器官的形态发育过程及Myosin Ⅵ的表达

目的探讨C57BL/6小鼠内耳前庭末梢器官的形态发育过程及MyosinⅥ在该过程中的表达。方法选择从E10到E20每个时间点的孕鼠,取E10～E17的胚胎头、E18～E20的胚胎内耳,通过冰冻连续切片、HE染色及免疫荧光观察小鼠内耳前庭末梢器官的形态发育过程及MyosinⅥ抗体标记阳性毛细胞出现的时间。结果小鼠内耳前庭末梢器官发育早、过程短,E10是听囊,E11已经能区分出背侧较大的前庭囊和腹侧较小的耳蜗囊,E12的前庭囊和耳蜗囊区分已很明显,并且出现内淋巴囊和管、上和后半规管始基,E13可见到上和后半规管壶腹嵴始基,出现水平半规管始基和椭圆囊始基,E14形成球囊和水平半规管壶腹嵴始基,E15椭圆囊、球囊、膜半规管初具成熟形态,所有囊斑、壶腹嵴基本形成,E18形态发育基本完成。MyosinⅥ标记阳性表达的毛细胞在E15的所有壶腹嵴、囊斑里出现,未见支持细胞表达MyosinⅥ。结论 MyosinⅥ在E15开始表达,这个时期可能是毛细胞成熟的关键时期。

肌源性调节蛋白MyoDl和肌球蛋白myosin在横纹肌肉瘤中的表达:免疫组织化学研究

应用免疫组织化学ＳＰ方法，检测了肌源性调节蛋白ＭｙｏＤｌ和肌球蛋白ｍ ｙｏｓｉｎ 在３８例横纹肌肉瘤（ＲＭＳ） 中的表达。结果显示ＭｙｏＤｌ阳性表达主要定位于ＲＭＳ瘤细胞的胞核中； ｍ ｙｏｓｉｎ 的阳性表达定位于ＲＭＳ瘤细胞的胞浆中， 二者的表达阳性率分别为６５．８％ 和５５．３％ 。在ＲＭＳ不同病理分型中ＭｙｏＤｌ和ｍ ｙｏｓｉｎ 的阳性表达均无显著性差异。但ＲＭＳ分化程度低，ＭｙｏＤｌ阳性表达增强，ｍ ｙｏｓｉｎ 阳性表达下降。Ｍｙｏ－Ｄｌ在Ⅲ级（低分化） 中的表达阳性率显著高于Ⅰ级（高分化）、Ⅱ级（中等分化） 中的表达阳性率（Ｐ＜ ０．０５，Ｐ＜ ０．０５）。ｍ ｙｏｓｉｎ 在Ⅰ级中的阳性率显著高Ⅲ级中的表达阳性率（Ｐ＜ ０．０５）。本文认为， ＭｙｏＤｌ表达增高、ｍ ｙｏｓｉｎ 表达下降，不仅是ＲＭＳ生物学行为的重要特征，也为改进低分化ＲＭＳ的病理诊断和ＲＭＳ早期诊断提供了有益的思路。

MyosinⅥ和Disabled-2表达水平对小鼠内毛细胞胞吞和胞饮作用的影响

目的:研究肌球蛋白Ⅵ(MyosinⅥ)和Disabled-2(Dab2)对小鼠内毛细胞(IHC)胞吞和胞饮的影响。方法:分离BALB/C小鼠基底膜,进行IHC原代培养,构建MyosinⅥ、Dab2基因重组过表达及RNAi载体并转染至IHC内。采用实时荧光定量PCR(qPCR)法检测各组细胞MyosinⅥ、Dab2 mRNA的表达水平,Western blotting法检测MyosinⅥ、Dab2蛋白的表达水平,划痕实验检测各组IHC迁移能力,并检测各组IHC胞饮和胞吞情况。结果:过表达联合组MyosinⅥ、Dab2mRNA及其蛋白表达水平,转染12 h、24 h、48 h、72 h后迁移距离、胞吞荧光颗粒数量均最高,而RNAi联合组上述指标均为最低(均P<0.05);胞饮实验显示,RNAi联合组IHC胞饮作用最弱,过表达联合组IHC胞饮作用最强(P<0.05)。结论:MyosinⅥ、Dab2均具有促进IHC胞吞和胞饮的作用,并具有协同作用。

MyosinV随机步长分布的动力学分析

MyosinV利用ATP水解所释放的自由能,朝肌动蛋白微丝正端作连续的定向运动,平均步长约为36nm。最近几年,诸多实验数据表明,myosinV步长并不固定为36nm,马达各步长值和相应步长出现概率的柱状图符合高斯分布;且在负载力大于2pN的情况下会出现“中间步长”和“后退步子”的现象。可根据已有实验数据,同时考虑马达在跃迁过程中所受的溶液摩擦阻力、常负载力和高斯随机力对其跃迁距离的影响,提出一种跃迁模型,并以此为基础对上述现象进行理论解释。

Myosin Va RNAi慢病毒载体的构建及对肺癌PG细胞运动和迁移能力的影响

目的构建人非常规肌球蛋白myosinVa基因RNAi慢病毒载体,并探讨其对人肺巨细胞癌PG细胞运动和迁移能力的影响。方法针对已经筛选确定的myosinVa基因RNAi有效靶序列,合成靶序列及其阴性对照的寡聚DNA,并连接到pSuper载体获得中间实验质粒pSuper-shM5A及阴性对照pSuper-shCON;然后将H1promoter-shM5A/shCON表达框重组到慢病毒载体plenti4上,分别得到plenti4-H1-shM5A和shCON载体,并进行慢病毒包装。随后用病毒上清感染PG细胞,并筛选出zeocin抗性的稳定细胞系PG-shM5A和shCON。通过RT-PCR方法检测PG-shM5A和shCON细胞的myosinVamRNA表达水平;用创伤愈合和Boyden小室实验测定PG-shM5A和shCON细胞的运动和迁移能力。结果限制性内切酶酶切和测序证实,成功构建myosinVaRNAi慢病毒载体plenti4-H1-shM5A。慢病毒包装成功后,感染PG细胞并获得zeocin抗性的细胞;用RT-PCR方法证明,myosinVamRNA被抑制70%以上。创伤愈合和Boyden小室实验表明,感染携带myosinVaRNAi慢病毒的PG细胞运动和迁移能力显著下调。结论成功构建myosinVaRNAi慢病毒载体plenti4-H1-shM5A,它能有效抑制人肺巨细胞癌PG细胞的myosinVa表达并降低其运动和迁移能力,初步揭示了myosinVa与肿瘤细胞恶性行为的相关性。

Myosin V定向运动的随机跃迁动力学研究

提出了MyosinV三态随机跃迁不等距定向运动的理论模型,得出漂移速度V、扩散系数D并将二者随ATP浓度及外力F的变化进行了曲线拟合,[ATP]不变的情况下速度与力关系的理论值与实验值吻合,定性的分析了MyosinV在不同ATP浓度下拖动负载运动时的动力学行为.

Effect of Anti-Cardiac Myosin Antibody on Prognosis of Patients with Acute Myocardial Infarction

Summary: To study whether there was an anti-cardiac myosin antibody (AMA) in serum of pa- tients with myocardial infarction (AMI), relationship between AMA and the prognosis in patients with AMI was investigated. In 67 patients with acute AMI, AMA was assayed by ELISA and left ventricular structure and cardiac function were examined by echocardiography at the end of the first week after infarction and during a 6-month follow-up. The patients with AMI were divided into AMA-positive group and AMA-negative group. The parameters of left ventricular end-dias- tolic function and prognosis were compared between the two groups. Results showed that the AMA was positive in 18 patients with AMI, with a positive rate of 26. 87 %, while it was negative in 20 health donors. The locations of myocardial infarction in the two groups were similar. There were significant differences in Killip class I (22. 22 % vs 55. 10 %, P<0. 05), decreasing of wall motion and ventricular aneurysm (92. 85 % vs 37. 5 %, P<0.01) between the positive group and the negative group. During a 6-month follow-up, the mortality was higher in AMA positive group than in AMA negative group (38. 89% vs 10. 20 %, P<0. 05). It is concluded that AMA can be detected in serum of patients with AMI and can serve as an important autoimmune marker. The autoimmune response might take place in AMI. AMA was associated with the left ventricular re- modeling and the prognosis of AMI.

Preliminary research on myosin light chain kinase in rabbit liver

AIM: To study preliminarily the properties of myosin light chain kinase (MLCK) in rabbit liver.METHODS: The expression of MLCK was detected by reverse transcription-polymerase chain reaction (RT-PCR);the MLCK was obtained from rabbit liver, and its activity was analyzed by γ-32P incorporation technique to detect the phosphorylation of myosin light chain.RESULTS: MLCK was expressed in rabbit liver, and the activity of the enzyme was similar to rabbit smooth muscle MLCK, and calmodulin-dependent. When the concentration was 0.65 mg-L-1, the activity was at the highest level.CONCLUSION: MLCK expressed in rabbit liver may catalyze the phosphorylation of myosin light chain, which may play important roles in the regulation of hepatic cell functions.

Induction of Cardiomyocyte Apoptosis by Anti-Cardiac Myosin Heavy Chain Antibodies in Patients with Acute Myocardial Infarction

Autoimmune is involved in the pathogenesis of ventricular remodeling in acute myocardial infarction (AMI).In the present study, we investigated the effect of anti-cardiac myosin heavy chain antibodies (AMHCA) from patients with AMI on rat cardiomyocyte apoptosis.Cardiomyocyte apoptosis was observed and measured by DNA end labeling and Annexin-Ⅴ/PI double-staining assay.The expression of apoptosis related p53 and Bcl-2 protein and the second messenger calcium were detected respectively by Western blotting, patch clamp and confocal calcium imaging.The results showed that AMHCA was able to induce cardiomyocyte apoptosis in a dose dependent manner.Apoptosis-accelerating nucleoprotein p53 was up-regulated, while apoptosis-inhibiting cytoplasmic protein Bcl-2 was down-regulated.In parallel, cytoplasmic calcium concentration was elevated.There was no effect on L-type calcium currents.It is concluded that AMHCA in patients with AMI as a novel triggering factor can induce cardiomyocyte apoptosis, which contributes to ventricular remodeling.

Myosin-Induced Autoimmune Myocarditis in BALB/C Mice

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Nonmuscle myosin Ⅱ regulates migration but not contraction in rat hepatic stellate cells

AIM: To identify and characterize the function of non-mu-scle myosin Ⅱ (NMM Ⅱ) isoforms in primary rat hepatic stellate cells (HSCs).METHODS: Primary HSCs were isolated from male Spra-gue-Dawley rats by pronase/collagenase digestion. Total RNA and protein were harvested from quiescent and culture-activated HSCs. NMM Ⅱ isoform (Ⅱ-A, Ⅱ-B and Ⅱ-C) gene and protein expression were measured by RealTime polymerase chain reaction and Western blot analyses respectively. NMM Ⅱ protein localization was visualized in vitro using immunocytochemical analysis. For in vivo assessment, liver tissue was harvested from bile duct-ligated (BDL) rats and NMM Ⅱisoform expression determined by immunohistochemistry. Using a selective myosin Ⅱ inhibitor and siRNA-mediated knockdown of each isoform, NMM Ⅱ functionality inprimary rat HSCs was determined by contraction and migration assays.RESULTS: NMM Ⅱ-A and Ⅱ-B mRNA expression was increased in culture-activated HSCs (Day 14) with sig-niflicant increases seen in all pairwise comparisons (Ⅱ-A: 12.67 ± 0.99 (quiescent) vs 17.36 ± 0.78 (Day 14), P < 0.05; Ⅱ-B: 4.94 ± 0.62 (quiescent) vs 13.90 ±0.85 (Day 14), P < 0.001). Protein expression exhibited similar expression patterns (Ⅱ-A: 1.87 ± 2.50 (quiescent) vs 58.64 ± 8.76 (Day 14), P < 0.05; Ⅱ-B: 1.17 ± 1.93 (quiescent) vs 103.71 ± 21.73 (Day 14), P < 0.05). No signif icant differences were observed in NMM Ⅱ-C mRNA and protein expression between quiescent and activated HSCs. In culture-activated HSCs, NMM Ⅱ-A and Ⅱ-B merged with F-actin at the cellular periphery and throughout cytoplasm respectively. In vitro stud-ies showed increased expression of NMM Ⅱ-B in HSCs activated by BDL compared to sham-operated animals. There were no apparent increases of NMM Ⅱ-A and Ⅱ-C protein expression in HSCs during hepatic BDL injury. To determine the contribution of NMM Ⅱ-A and Ⅱ-B to migration and contraction, NMM Ⅱ-A and Ⅱ-B expres-sion were downregulated with siRNA. NMM Ⅱ-A and/or Ⅱ-B siRNA inhibited HSC migration by approximately 25% compared to scramble siRNA-treated cells. Conversely, siRNA-mediated NMM Ⅱ-A and Ⅱ-B inhibition had no signif icant effect on HSC contraction; however, contraction was inhibited with the myosin Ⅱ inhibitor, blebbistatin (38.7% ± 1.9%).CONCLUSION: Increased expression of NMM Ⅱ-A and Ⅱ-B regulates HSC migration, while other myosin Ⅱclasses likely modulate contraction, contributing to development and severity of liver f ibrosis.

Effect of aerobic exercise on the contractile function of gastrocnemius myosin heavy chain

Objective To study the effect of 4-6 weeks' treadmill training of male SD rats on the contractile function of their gastrocnemius myosin heavy chain (MHC). Methods Forty male SD rats were randomly divided into control group and training group. The treadmill training of the training group rats was incessantly performed for 4-6 weeks at an intensity of about 75% VO2max (18.5-24 m/min,gradient of 0°,each training session lasting 50 minutes,twice a day). The content of gastrocnemius MHC mRNA was tested by reverse transcription polymerase chain reaction (RT-PCR),and the changes of muscle fibre and its cross-section area (CSA) were measured using immunohistochemistry. Electric stimulation tests were used to determine the maximal tension of isometric contraction of the post-training gastrocnemius. Results ① After continuous treadmill training for 4-6 weeks,we found that the content of the total MHC,MHC Ⅰ,MHC Ⅱx,MHC Ⅱa mRNAs was 105%,105%,109% and 108% of that in the resting control group,respectively,and the MHC Ⅱb mRNA content did not change significantly. The percentage of MHC Ⅰ mRNA in the total MHC mRNA increased while that of MHC Ⅱ mRNA decreased after aerobic training. ② The slow type of fibre type Ⅰ was the main part of the MHC after training and the CSA of the muscle fibres increased simultaneously. ③ The maximal tension of isometric contraction by pulse stimulation of square wave in the training group increased significantly compared with that in the control group (P<0.01). Conclusion The findings indicate that aerobic exercise may promote an increase in the contractile function of MHC.

Agaro-Oligosaccharides Prevent Myostatin Hyperexpression and Myosin Heavy Chain Protein Degradation in C2C12 Myotubes Induced by Tumor Necrosis Factor-<i>α</i>

Myostatin is a major factor involved in the regulation of skeletal muscle protein mass. High myostatin levels have been associated with an increase in myotube shrinkage. Enhanced myostatin expression is caused by pro-catabolic reactions involving compounds such as tumor necrosis factor (TNF)-α. The present study investigated the effects of agaro-oligosaccharides (AOSs) on hypercatabolism of myotubes exposed to TNF-α. C2C12 myotubes exposed to TNF-α in the presence or absence of AOSs. Myotube exposure to TNF-α resulted in a reduction in the amount of myosin heavy chain (MyHC) protein and a decrease in myotube diameter, which was associated with increased myostatin mRNA expression. AOSs prevented TNF-α-induced MyHC protein loss and restored normal myostatin mRNA levels, with agarobiose and agarotetraose effectively suppressing the hyperexpression of the mRNA. In addition, expression levels of the known myostatin inhibitors, latent transforming growth factor beta binding protein 3 (Ltbp3) and growth and differentiation factor-associated serum protein 1 (Gasp1) mRNAs, decreased more in TNF-α-induced myotubes than in the TNF-α-free control, possibly resulting in myostatin upregulation. However, AOSs restored nearly normal expression levels of Ltbp3 and Gasp1 mRNA, potentially suppressing myostatin expression. These findings suggest that AOSs could prevent myotube shrinkage induced by TNF-α.

Detection of cardiac myosin binding protein-C (cMyBP-C) by a phospho-specific PKD antibody in contracting rat cardiomyocytes

Protein phosphorylation plays an important role in physiological processes, such as muscle contraction. Phospho-specific antibodies have become powerful tools to study these processes. Cardiac myosin binding protein-C (cMyBP-C) is one of the proteins that make up the contractile apparatus of cardiomyocytes. Phosphorylation of cMyBP-C is essential for normal cardiac function, since dephosphorylation of this protein leads to its degradation and has been associated with cardiomyopathy. One of the upstream kinases, which phosphorylate cMyBP-C, is protein kinase D (PKD). While studying the role of PKD in cMyBP-C phosphorylation, we tried to analyze phosphorylation of PKD with a phospho-specific PKD-Ser744/748 antibody. Contrary to the expected 115 kDa, a signal was found for a 150-kDa protein. By MALDI-TOF mass spectrometry, we identified this protein to be cMyBP-C. These data were confirmed by immunostaining using the p-PKD-Ser744/748 antibody, which displayed a striated pattern similar to the one observed for a regular cMyBP-C antibody. To our knowledge there are no antibodies commercially available for phosphorylated cMyBP-C. Thus, the p-PKD-Ser744/748 antibody can accelerate research into the role of cMyBP-C phosphorylation in cardiomyocytes.

Glabridin and Anti-Non-Muscle Myosin IIA Therapy Disrupts Non-Small Cell Lung Carcinoma Motility

Lung cancer is the leading cause of cancer related death in the United States killing over 130,000 people each year. While a combination of chemo and radiation therapy may be effective, surgery is still required for many patients. Without surgery, the disease may progress and lead to metastases. We sought to determine if treatment with anti-non-muscle myosin IIA antibody would inhibit movement of the cells in the presence and absence of glabridin (an isoflavonoid compound shown to inhibit cell migration by inhibiting myosin). We compared inhibition by glabridin to that of an anti-non-muscle myosin IIA antibody and a combination therapy of both at 12 and 24 hours post wound creation. Cells that took up the anti-non-muscle myosin IIA antibody were greatly inhibited in motility and exhibited no significant change in wound healing. Glabridin treatment resulted in a dramatic increase in wound size within 12 hours and regeneration within 24 hours. The greatest decrease in motility was observed in cells treated with the combination of both glabridin and anti-non-muscle myosin IIA antibody. By 24 hrs, cell migration had halted due to death of the cells resulting from this combination. Further testing needs to be done to determine a safe mode of delivery of the combination therapy to ensure only local distribution. Controlled release drug delivery depot systems have been used as a means to provide local release of drugs intra-tumorally or adjacent to the cancerous tissue after surgical resection and have great potential.

禾谷镰刀菌肌球蛋白(Myosin Ⅰ)生物信息学分析及原核表达与纯化

肌球蛋白(MyosinⅠ)是新型杀菌剂氰烯菌酯的靶标蛋白,为探究禾谷镰刀菌(Fusarium graminearum)中MyosinⅠ的三维结构及其与氰烯菌酯的互作机制,进一步阐释禾谷镰刀菌对氰烯菌酯潜在的抗性机理,本研究采用生物信息学方法对MyosinⅠ氨基酸序列进行分析,结果表明:该蛋白分子量大小为134.9ku,等电点为9.47,不具有信号肽,属非分泌型蛋白,无跨膜区,是亲水性蛋白,具有MYSc保守结构域。并采用结构生物学的方法,以禾谷镰刀菌(F.graminearum)cDNA为模板,根据MyosinⅠ重要功能域序列设计特异性引物进行PCR扩增,克隆了MyosinⅠ重要功能域基因并构建了三个功能域蛋白表达载体pHAT2-MyosinⅠ39-720,pETM20-MyosinⅠ39-720,pETM30-MyosinⅠ39-720,将重组表达载体转化到大肠杆菌BL21(BE3)中,并利用异丙基硫代半乳糖苷(IPTG)进行诱导表达,结果表明:主要功能域蛋白在大肠杆菌中表达,但主要以包涵体的形式存在。对该蛋白的生物信息学分析及表达纯化为其结构功能的分析及其与氰烯菌酯互作机制的研究奠定了基础。