The degradation of titin could make the myofibrillar fragmentation to improve meat tenderization during postmortem.This study aimed to investigate effect of phosphorylation on titin degradation.Protein kinase A(PKA)an...The degradation of titin could make the myofibrillar fragmentation to improve meat tenderization during postmortem.This study aimed to investigate effect of phosphorylation on titin degradation.Protein kinase A(PKA)and alkaline phosphatase(AP)were added to crude titin extracted from ovine longissimus lumborum(LL)muscles.Phosphorylated/dephosphorylated titin were incubated withμ-calpain at 4℃ for 2 days.Results showed titin in AP group started degradation earlier than that in PKA and control groups.There were 20,16 and 12 phosphorylated sites identified by iTRAQ in the PKA,control and AP group,respectively.3D structure of dephosphorylated titin fragment was simulated and its molecular dynamics trajectory analysis was performed using Discovery StudioTM.The dihedral angle in AP group was less and the dephosphorylated fragment had a higher kinetic energy and total energy.We suggested that changes caused by AP treatment might make titin unstable,which easily degraded byμ-calpain.展开更多
目的:通过检测不同分组患者血清中乙酰胆碱受体抗体(AchR-Ab)、连接素抗体(Titin antibodies,Titin-Ab)和兰尼碱受体抗体(Ryanodine receptor,RyR-Ab)的表达,探讨以上三种抗体在重症肌无力(myasthenia ggravis,MG)诊断和治疗中的临床意...目的:通过检测不同分组患者血清中乙酰胆碱受体抗体(AchR-Ab)、连接素抗体(Titin antibodies,Titin-Ab)和兰尼碱受体抗体(Ryanodine receptor,RyR-Ab)的表达,探讨以上三种抗体在重症肌无力(myasthenia ggravis,MG)诊断和治疗中的临床意义。方法:应用ELISA法对34例MG合并胸腺病变且接受胸腺完整切除的患者,28例其他神经系统疾病的患者和30例正常健康者的血清内进行AchR抗体、Titin抗体和RyR抗体的检测,并于MG合并胸腺病变患者行胸腺切除术后1周及术后3个月时重复检测。结果:MG合并胸腺病变组患者血清内的AchR抗体、Titin抗体要明显高于其他两对照组(P<0.01),RyR抗体水平亦高于其他两组(P<0.05);伴胸腺瘤的重症肌无力(mg with thymoma,MGT)组患者的Titin抗体、RyR抗体明显高于伴胸腺增生的重症肌无力(mg with thymic hyperplasia,MGH)和伴胸腺囊肿的重症肌无力(mg with thymic cyst,MGC)组患者(P<0.01),AchR抗体对MGT组患者亦有较高的阳性率(P<0.05);胸腺切除治疗后仅MGT组患者的AchR-Ab在第一周即发生明显下降(P<0.01),RyR-Ab在术后3个月时有下降(P<0.05),而其他组MG患者的三种抗体均未发现在胸腺切除前后有何变化(P>0.05)。结论:AchR-Ab、Titin-Ab和RyR-Ab与MG的发病机制有关;三种抗体均有助于对MG患者的诊断,其中Titin-Ab和RyR-Ab可用于胸腺瘤的鉴别诊断,并可作为诊断MGT的主要客观指标;对于MGT经胸腺切除术后患者可通过检测AchR抗体观察早期病情改变,检测RyR-Ab亦可作为其中远期病情改变的客观指标,但这两项指标与患者预后恢复情况的相关性还有待于进一步研究。展开更多
基金financially supported by National Natural Science Foundation(32102035)the Agricultural Science and Technology Innovation Program(CAAS-ASTIP-2020-IFST-03)Central Public-interest Scientific Institution Basal Research(S2019RCJC01,S2020JBKY-16).
文摘The degradation of titin could make the myofibrillar fragmentation to improve meat tenderization during postmortem.This study aimed to investigate effect of phosphorylation on titin degradation.Protein kinase A(PKA)and alkaline phosphatase(AP)were added to crude titin extracted from ovine longissimus lumborum(LL)muscles.Phosphorylated/dephosphorylated titin were incubated withμ-calpain at 4℃ for 2 days.Results showed titin in AP group started degradation earlier than that in PKA and control groups.There were 20,16 and 12 phosphorylated sites identified by iTRAQ in the PKA,control and AP group,respectively.3D structure of dephosphorylated titin fragment was simulated and its molecular dynamics trajectory analysis was performed using Discovery StudioTM.The dihedral angle in AP group was less and the dephosphorylated fragment had a higher kinetic energy and total energy.We suggested that changes caused by AP treatment might make titin unstable,which easily degraded byμ-calpain.
文摘目的:通过检测不同分组患者血清中乙酰胆碱受体抗体(AchR-Ab)、连接素抗体(Titin antibodies,Titin-Ab)和兰尼碱受体抗体(Ryanodine receptor,RyR-Ab)的表达,探讨以上三种抗体在重症肌无力(myasthenia ggravis,MG)诊断和治疗中的临床意义。方法:应用ELISA法对34例MG合并胸腺病变且接受胸腺完整切除的患者,28例其他神经系统疾病的患者和30例正常健康者的血清内进行AchR抗体、Titin抗体和RyR抗体的检测,并于MG合并胸腺病变患者行胸腺切除术后1周及术后3个月时重复检测。结果:MG合并胸腺病变组患者血清内的AchR抗体、Titin抗体要明显高于其他两对照组(P<0.01),RyR抗体水平亦高于其他两组(P<0.05);伴胸腺瘤的重症肌无力(mg with thymoma,MGT)组患者的Titin抗体、RyR抗体明显高于伴胸腺增生的重症肌无力(mg with thymic hyperplasia,MGH)和伴胸腺囊肿的重症肌无力(mg with thymic cyst,MGC)组患者(P<0.01),AchR抗体对MGT组患者亦有较高的阳性率(P<0.05);胸腺切除治疗后仅MGT组患者的AchR-Ab在第一周即发生明显下降(P<0.01),RyR-Ab在术后3个月时有下降(P<0.05),而其他组MG患者的三种抗体均未发现在胸腺切除前后有何变化(P>0.05)。结论:AchR-Ab、Titin-Ab和RyR-Ab与MG的发病机制有关;三种抗体均有助于对MG患者的诊断,其中Titin-Ab和RyR-Ab可用于胸腺瘤的鉴别诊断,并可作为诊断MGT的主要客观指标;对于MGT经胸腺切除术后患者可通过检测AchR抗体观察早期病情改变,检测RyR-Ab亦可作为其中远期病情改变的客观指标,但这两项指标与患者预后恢复情况的相关性还有待于进一步研究。
