scholarly journals Nonmuscle Myosin Heavy Chain ⅡA-Mediated Exosome Release via Regulation of the Rho-Associated Kinase 1/Myosin Light Chains/Actin Pathway

2020 ◽  
Vol 11 ◽  
Author(s):  
Yanni Lv ◽  
Jin Chen ◽  
Jinfang Hu ◽  
Yisong Qian ◽  
Ying Kong ◽  
...  
Keyword(s):  
Protein Expression ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Molecular Motors ◽  
Molecular Motor ◽  
Microglial Cells ◽  
Potential Mechanism ◽  
Nonmuscle Myosin ◽  
Western Blots ◽  
Positive Rate

Nonmuscle myosin ⅡA, a kind of ATP-dependent molecular motor, binds actin to form the molecular motors of the cell. We found that interfering with nonmuscle myosin heavy chain (NMMHC) ⅡA could affect the exosome release from microglial cells stimulated by LPS. LPS could enhance exosome release from microglial cells by increasing exosome concentration, elevating the rate of positively labeled CD9 and CD81 proteins and protein expression. The myosin inhibitor, blebbistatin, could decrease the concentration of released exosome and reduce CD9 and CD81 protein expression on the exosome surface compared with that in the LPS group. To further determine the exact subtype of myosin Ⅱ responsible for these effects, we transfected microglial cells with siRNA for MYH9, MYH10, and MYH14. The data showed that only the transfection of siRNA-MYH9, but not MYH10 or MYH14 could decrease the released exosome concentration and particle size compared with those in the LPS group. siRNA-MYH9 would also weaken the CD9 and CD81 protein positive rate and protein expression compared with that in the LPS group by the quantification of CD9 and CD81 fluorescence intensities and by western blotting. Western blots and immunofluorescence assays indicated that NMMHC ⅡA might trigger the ROCK1/MLC/actin signaling pathway of microglial cells upon stimulation by LPS, which might be the potential mechanism of exosome release. These observations demonstrated that NMMHC ⅡA might be the potential target required for exosome release.

scholarly journals Immunochemical and immunocytochemical identification of a myosin heavy chain polypeptide in Nicotiana pollen tubes

1989 ◽  
Vol 92 (4) ◽  
pp. 569-574
Author(s):  
X.J. Tang ◽  
P.K. Hepler ◽  
S.P. Scordilis
Keyword(s):  
Pollen Tube ◽  
Nuclear Envelope ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Immunofluorescence Microscopy ◽  
Generative Cell ◽  
Pollen Tubes ◽  
Nuclear Surface ◽  
Common Pattern ◽  
Western Blots

A myosin heavy chain polypeptide has been identified and localized in Nicotiana pollen tubes using monoclonal anti-myosin antibodies. The epitopes of these antibodies were found to reside on the myosin heavy chain head and rod portion and were, therefore, designated anti-S-1 (myosin S-1) and anti-LMM (light meromyosin). On Western blots of the total soluble pollen tube proteins, both anti-S-1 and anti-LMM label a polypeptide of approximately 175,000 Mr. Immunofluorescence microscopy shows that both antibodies yield numerous fluorescent spots throughout the whole length of the tube, often with an enrichment in the tube tip. These fluorescent spots are thought to represent vesicles and/or organelles in the pollen tubes. In addition to this common pattern, anti-S-1 stains both the generative cell and the vegetative nuclear envelope. The different staining patterns of the nucleus between anti-S-1 and anti-LMM may be caused by some organization and/or anchorage state of the myosin molecules on the nuclear surface that differs from those on the vesicles and/or organelles.

B2 exon splicing of nonmuscle myosin heavy chain IIB is differently regulated in developing and adult rat brain

2000 ◽  
Vol 37 (4) ◽  
pp. 299-306 ◽  
Author(s):  
Taisuke Miyazaki ◽  
Masahiko Watanabe ◽  
Akihiko Yamagishi ◽  
Masayuki Takahashi
Keyword(s):  
Myosin Heavy Chain ◽  
Rat Brain ◽  
Heavy Chain ◽  
Nonmuscle Myosin ◽  
Adult Rat ◽  
Exon Splicing ◽  
Adult Rat Brain

Denervation-induced changes in myosin heavy chain expression in the rat diaphragm muscle

2003 ◽  
Vol 95 (2) ◽  
pp. 611-619 ◽  
Author(s):  
Paige C. Geiger ◽  
Jeffrey P. Bailey ◽  
Wen-Zhi Zhan ◽  
Carlos B. Mantilla ◽  
Gary C. Sieck
Keyword(s):  
Protein Expression ◽  
Mrna Expression ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Protein Isoforms ◽  
Diaphragm Muscle ◽  
Northern Analysis ◽  
Mrna Levels ◽  
Rat Diaphragm ◽  
Mrna Isoforms

Unilateral denervation (Dnv) of the rat diaphragm muscle (Diam) markedly alters expression of myosin heavy chain (MHC) isoforms. After 2 wk of Diam Dnv, MHC content per half-sarcomere decreases in fibers expressing MHC2X and MHC2B. We hypothesized that changes in MHC protein expression parallel changes in MHC mRNA expression. Relative MHC isoform mRNA levels were determined by Northern analysis after 1, 3, 7, and 14 days of Dnv of the rat Diam. MHC protein expression was determined by SDS-PAGE. Changes in MHC isoform protein and mRNA expression were not concurrent. Expression of MHCSlow and MHC2X mRNA isoforms decreased dramatically by 3 days of Dnv, whereas that of MHC2A and MHC2B did not change. Expression of all MHC protein isoforms decreased by 3 days of Dnv. We observed a differential effect of rat Diam Dnv on MHC isoform protein and mRNA expression. The time course of the changes in MHC isoform mRNA and protein expression suggests a predominant effect of altered protein turnover rates on MHC protein expression instead of altered transcription after Dnv.

In Situ Interleukin-6 Transcription in Embryonic Nonmuscle Myosin Heavy Chain Expressing Immature Mesenchyme Cells of Cardiac Myxoma

2000 ◽  
Vol 9 (1) ◽  
pp. 33-37 ◽  
Author(s):  
Jun-ichi Suzuki ◽  
Kei Takayama ◽  
Fujio Mitsui ◽  
Tetsuya Kono ◽  
Yoshikazu Yazaki ◽  
...  
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Interleukin 6 ◽  
Cardiac Myxoma ◽  
Nonmuscle Myosin ◽  
Mesenchyme Cells

scholarly journals Many chronic lymphocytic leukemia antibodies recognize apoptotic cells with exposed nonmuscle myosin heavy chain IIA: implications for patient outcome and cell of origin

Blood ◽  
2010 ◽  
Vol 115 (19) ◽  
pp. 3907-3915 ◽  
Author(s):  
Charles C. Chu ◽  
Rosa Catera ◽  
Lu Zhang ◽  
Sebastien Didier ◽  
Briana M. Agagnina ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Lymphocytic Leukemia ◽  
Apoptotic Cells ◽  
Nonmuscle Myosin ◽  
Cell Of Origin ◽  
Poor Clinical Outcome ◽  
Mutation Status ◽  
Poor Patient Survival

Abstract Many B-cell chronic lymphocytic leukemia (CLL) monoclonal antibodies (mAbs) can be grouped into subsets based on nearly identical stereotyped sequences. Subset 6 CLL mAbs recognize nonmuscle myosin heavy chain IIA (MYHIIA). Herein, we report that during apoptosis, MYHIIA becomes exposed on the cell surface of a subgroup of apoptotic cells, allowing subset 6 CLL mAbs to bind with it. Because other non–subset 6 CLL mAbs interact with apoptotic cells, 26 CLL mAbs, including 24 not belonging to subset 6, were tested for reactivity with MYHIIA-exposed apoptotic cells (MEACs). More than 60% of CLL mAbs bound MEACs well; most of these mAbs expressed unmutated IGHV (15 of 16) and belonged to a stereotyped subset (14 of 16). Binding to MEACs inversely correlated with the degree of IGHV mutation. Interestingly, high binding to MEACs significantly correlated with poor patient survival, suggesting that the basis of IGHV mutation status as a CLL prognostic factor reflects antigen binding. Finally, natural antibodies from human serum also reacted with MEACs. Taken together, our data indicate that a large proportion of CLL clones emerge from natural antibody-producing cells expressing immunoglobulins that recognize MEACs, and that this reactivity is associated with poor clinical outcome.

scholarly journals Function of the Neuron-specific Alternatively Spliced Isoforms of Nonmuscle Myosin II-B during Mouse Brain Development

2006 ◽  
Vol 17 (5) ◽  
pp. 2138-2149 ◽  
Author(s):  
Xuefei Ma ◽  
Sachiyo Kawamoto ◽  
Jorge Uribe ◽  
Robert S. Adelstein
Keyword(s):  
Amino Acids ◽  
Myosin Heavy Chain ◽  
Purkinje Cells ◽  
Heavy Chain ◽  
Myosin Ii ◽  
Nonmuscle Myosin ◽  
Binding Region ◽  
Alternatively Spliced ◽  
Cerebellar Purkinje Cells ◽  
Mouse Brain Development

We report that the alternatively spliced isoforms of nonmuscle myosin heavy chain II-B (NHMC II-B) play distinct roles during mouse brain development. The B1-inserted isoform of NMHC II-B, which contains an insert of 10 amino acids near the ATP-binding region (loop 1) of the myosin heavy chain, is involved in normal migration of facial neurons. In contrast, the B2-inserted isoform, which contains an insert of 21 amino acids near the actin-binding region (loop 2), is important for postnatal development of cerebellar Purkinje cells. Deletion of the B1 alternative exon, together with reduced expression of myosin II-B, results in abnormal migration and consequent protrusion of facial neurons into the fourth ventricle. This protrusion is associated with the development of hydrocephalus. Restoring the amount of myosin II-B expression to wild-type levels prevents these defects, showing the importance of total myosin activity in facial neuron migration. In contrast, deletion of the B2 alternative exon results in abnormal development of cerebellar Purkinje cells. Cells lacking the B2-inserted isoform show reduced numbers of dendritic spines and branches. Some of the B2-ablated Purkinje cells are misplaced in the cerebellar molecular layer. All of the B2-ablated mice demonstrated impaired motor coordination.

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