To understand the function of Mayven and investigate the pathogenesis of multiple sclerosis, the gene sequences of different truncated Mayven were amplified from the gene library of human brain. These truncated fragments, including fragment P1 (1-902 bp), fragment P2 (1-523 bp), fragment P3 (507-182 bp) and fragment P4 (887-1782 bp), were cloned into pGEX-4T-2 vector to construct recombinant plasmids. The recombinant plasmids were transformed into E. coli BL21(DE3) and induced to express by IPTG. The expressed proteins were detected by SDS-PAGE and Western blot, and were purified by GST purifying system. The results showed that recombinant express vectors of different truncated GST-Mayven were successfully constructed and were expressed in soluble form protein induced by IPTG. The fusion proteins have good reactivity to GST antibody. The construction of recombinant express vectors of different truncated GST-Mayven lays a basis for further function study on Mayven.
Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; Humans ; Microfilament Proteins ; genetics ; metabolism ; Multiple Sclerosis ; genetics ; Nerve Tissue Proteins ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism

OBJECTIVETo investigate the role of autophagy on the pathogenesis of spinocerebellar ataxia 3/Machado-Joseph disease (SCA3/MJD).

METHODSHEK293 cells expressing polyglutamine-expanded ataxin-3 were used as cell model for SCA3/MJD. The level of polyglutamine-expanded ataxin-3 was detected after cells were treated with different inhibitors or inducer of autophagy.

RESULTSInhibition of autophagy increased aggregate formation and cell death in HEK293 cells expressing mutated ataxin-3, and vice versa.

CONCLUSIONThe data suggested that autophagy is involved in the degradation of mutant ataxin-3, resulting in a decrease in the proportions of aggregate-containing cells and cell death in HEK293 cells expressing polyglutamine-expanded ataxin-3. It is possible that autophagy may be applied as a potential therapeutic approach for SCA3/MJD.

Ataxin-3 ; Autophagy ; Cell Line ; Humans ; Machado-Joseph Disease ; genetics ; metabolism ; physiopathology ; Mutation ; Nerve Tissue Proteins ; genetics ; metabolism ; Nuclear Proteins ; genetics ; metabolism ; Peptides ; metabolism ; Repressor Proteins ; genetics ; metabolism

To date, nearly 28 distinct genetic loci of autosomal dominant cerebellar ataxias have been identified, among them 18 disease-causing genes have been cloned. Of these, Machado-Joseph disease (MJD), also named as spinocerebellar ataxia type 3 (SCA3), is perhaps the most common subtype among different races and origins in the world. It is a neurodegenerative disease caused by the expansion of a CAG repeat in the coding region of the MJD1 gene, with obvious clinical and genetic heterogeneity. In this review, authors covered the recent advances in molecular genetic of SCA3/MJD.
Ataxin-3 ; Humans ; Machado-Joseph Disease ; genetics ; Molecular Biology ; Mutation ; Nerve Tissue Proteins ; chemistry ; genetics ; metabolism ; Nuclear Proteins ; chemistry ; genetics ; metabolism ; Repressor Proteins ; chemistry ; genetics ; metabolism

Enterovirus 71 (EV71) is a neurotropic pathogen that can induce hand, foot and mouth disease in children. There is an appreciable mortality rate after EV71 infections. The mechanism of action of EV71 replication is not known. Recent work has identified some of cell factors of the host that participate in the synthesis of the RNA and proteins of EV71 (e.g., hnRNP K, reticulon 3 (RTN 3)). In that work, researchers used a competitive assay to show that hnRNP K can interact with EV71 5' UTR, which is required for efficient synthesis of viral RNA. Using a yeast two-hybrid system, other researchers demonstrated that RTN 3 interacts with the N-terminal domain of EV71 2C, which is crucial for replication of viral RNA. Here, we discuss recent work focusing on the molecular mechanisms of hnRNP K and RTN 3 in the synthesis of the RNA and proteins of EV71.
Animals ; Carrier Proteins ; genetics ; metabolism ; Enterovirus A, Human ; genetics ; physiology ; Enterovirus Infections ; genetics ; metabolism ; virology ; Heterogeneous-Nuclear Ribonucleoprotein K ; Host-Pathogen Interactions ; Humans ; Membrane Proteins ; genetics ; metabolism ; Nerve Tissue Proteins ; genetics ; metabolism ; Ribonucleoproteins ; genetics ; metabolism ; Viral Proteins ; genetics ; metabolism ; Virus Replication

OBJECTIVETo explore the subcellular localization of ataxin-3 and the effect of polyglutamine (polyQ) expansion mutation on the morphology of mitochondrion, golgi apparatus and endoplasmic reticulum.

METHODSTransient transfection was employed to build cell models expressing wild-type or mutant ataxin-3 proteins. Indirect immunofluorescence was applied to identify markers of organelle membrane. The results were observed under a laser scanning confocal microscope.

RESULTSNo co-localization was observed for ataxin-3 protein and mitochondrial marker TOM20, but the percentage of cells with mitochondrial fragmentation has increased in cells expressing mutant ataxin-3 (P<0.05). No co-localization was observed for ataxin-3 protein and golgi marker GM130, and mutant ataxin-3 did not cause golgi fragmentation. Wide type and polyQ-expanded ataxin-3 both showed partial co-localization with ER marker calnexin. The latter showed more overlap with calnexin, and the overlapping signals were mostly located in the places where aggregates were situated.

CONCLUSIONPolyQ-expanded ataxin-3 protein may indirectly affect the integrity of mitochondria, but may cause no effect on the structure and functions of golgi apparatus. Endoplasmic reticulum may be another place where extended ataxin-3 protein can induce cytotoxicity in addition to the nucleus.

Ataxin-3 ; Cytoplasm ; genetics ; metabolism ; Endoplasmic Reticulum ; genetics ; metabolism ; HeLa Cells ; Humans ; Machado-Joseph Disease ; genetics ; metabolism ; Mitochondria ; genetics ; metabolism ; Nerve Tissue Proteins ; genetics ; metabolism ; Nuclear Proteins ; genetics ; metabolism ; Protein Transport ; Repressor Proteins ; genetics ; metabolism

OBJECTIVETo introduce the eukaryotic expression vector pEGFP-C1-PDX-1 into nestin-positive cell derived from bone marrow stromal cells by nucleofection and optimize the conditions for transfection.

METHODSThe recombinant plasmid was transfected into bone marrow stromal cells-derived nestin-positive cells with varied DNA quantities or the serum concentration in the medium. The expression of PDX-1 gene in the transfected cells was detected by RT-PCR.

RESULTSSatisfactory efficiency of transfection was achieved with the DNA quantity of 2-10 microg and medium serum concentration of 20%. PDX-1 expression was detected in the transfected cells by RT-PCR.

CONCLUSIONThe optimized transfection conditions result in enhanced efficiency of PDX-1 gene transfection into nestin-positive cells derived from bone marrow stromal cells, which may serve as the seed cells in tissue-engineering.

Bone Marrow Cells ; metabolism ; Genetic Vectors ; Homeodomain Proteins ; genetics ; Humans ; Intermediate Filament Proteins ; metabolism ; Nerve Tissue Proteins ; metabolism ; Nestin ; Plasmids ; Stromal Cells ; metabolism ; Trans-Activators ; genetics ; Transfection ; methods

Leucine-rich repeats containing 4 ( LRRC4 , also named netrin-G ligand 2 [NGL-2]) is a member of the NetrinGs ligands (NGLs) family. As a gene with relatively high and specific expression in brain, it is a member of the leucine-rich repeat superfamily and has been proven to be a suppressor gene for gliomas, thus being involved in gliomagenesis. LRRC4 is the core of microRNA-dependent multi-phase regulatory loops that inhibit the proliferation and invasion of glioblastoma (GB) cells, including LRRC4/NGL2-activator protein 2 (AP2)-microRNA (miR) 182-LRRC4 and LRRC4-miR185-DNA methyltransferase 1 (DNMT1)-LRRC4/specific protein 1 (SP1)-DNMT1-LRRC4. In this review, we demonstrated LRRC4 as a new member of the partitioning-defective protein (PAR) polarity complex that promotes axon differentiation, mediates the formation and plasticity of synapses, and assists information input to the hippocampus and storage of memory. As an important synapse regulator, aberrant expression of LRRC4 has been detected in autism, spinal injury and GBs. LRRC4 is a candidate susceptibility gene for autism and a neuro-protective factor in spinal nerve damage. In GBs, LRRC4 is a novel inhibitor of autophagy, and an inhibitor of protein-protein interactions involving in temozolomide resistance, tumor immune microenvironment, and formation of circular RNA.
Humans ; Cell Line, Tumor ; Glioblastoma/metabolism* ; Leucine ; Leucine-Rich Repeat Proteins/genetics* ; MicroRNAs ; Nerve Tissue Proteins/genetics* ; Tumor Microenvironment

Mammalian cells are frequently at risk of DNA damage from both endogenous and exogenous sources. Accordingly, cells have evolved the DNA damage response (DDR) pathways to monitor and assure the integrity of their genome. In cells, the intact and effective DDR is essential for the maintenance of genomic stability and it acts as a critical barrier to suppress the development of cancer in humans. Two central kinases for the DDR pathway are ATM and ATR, which can phosphorylate and activate many downstream proteins for cell cycle arrest, DNA repair, or apoptosis if the damages are irreparable. In the last several years, we and others have made significant progress to this field by identifying BRIT1 (also known as MCPH1) as a novel key regulator in the DDR pathway. BRIT1 protein contains 3 breast cancer carboxyl terminal (BRCT) domains which are conserved in BRCA1, MDC1, 53BP1, and other important molecules involved in DNA damage signaling, DNA repair, and tumor suppression. Our in vitro studies revealed BRIT1 to be a chromatin-binding protein required for recruitment of many important DDR proteins (ATM, MDC1, NBS1, RAD51, BRCA2) to the DNA damage sites. We recently also generated the BRIT1 knockout mice and demonstrated its essential roles in homologous recombination DNA repair and in maintaining genomic stability in vivo. In humans, BRIT1 is located on chromosome 8p23.1, where loss of hetero-zigosity is very common in many types of cancer. In this review, we will summarize the novel roles of BRIT1 in DDR, describe the relationship of BRIT1 deficiency with cancer development, and also discuss the use of synthetic lethality approach to target cancers with HR defects due to BRIT1 deficiency.
Animals ; Chromosomal Proteins, Non-Histone/genetics/metabolism/*physiology ; DNA Damage/genetics/*physiology ; DNA Repair/genetics/*physiology ; Humans ; Mice ; Models, Biological ; Neoplasms/*genetics ; Nerve Tissue Proteins/genetics/metabolism/*physiology

Mammalian cells are frequently at risk of DNA damage from both endogenous and exogenous sources. Accordingly, cells have evolved the DNA damage response (DDR) pathways to monitor and assure the integrity of their genome. In cells, the intact and effective DDR is essential for the maintenance of genomic stability and it acts as a critical barrier to suppress the development of cancer in humans. Two central kinases for the DDR pathway are ATM and ATR, which can phosphorylate and activate many downstream proteins for cell cycle arrest, DNA repair, or apoptosis if the damages are irreparable. In the last several years, we and others have made significant progress to this field by identifying BRIT1 (also known as MCPH1) as a novel key regulator in the DDR pathway. BRIT1 protein contains 3 breast cancer carboxyl terminal (BRCT) domains which are conserved in BRCA1, MDC1, 53BP1, and other important molecules involved in DNA damage signaling, DNA repair, and tumor suppression. Our in vitro studies revealed BRIT1 to be a chromatin-binding protein required for recruitment of many important DDR proteins (ATM, MDC1, NBS1, RAD51, BRCA2) to the DNA damage sites. We recently also generated the BRIT1 knockout mice and demonstrated its essential roles in homologous recombination DNA repair and in maintaining genomic stability in vivo. In humans, BRIT1 is located on chromosome 8p23.1, where loss of hetero-zigosity is very common in many types of cancer. In this review, we will summarize the novel roles of BRIT1 in DDR, describe the relationship of BRIT1 deficiency with cancer development, and also discuss the use of synthetic lethality approach to target cancers with HR defects due to BRIT1 deficiency.
Animals ; Chromosomal Proteins, Non-Histone/genetics/metabolism/*physiology ; DNA Damage/genetics/*physiology ; DNA Repair/genetics/*physiology ; Humans ; Mice ; Models, Biological ; Neoplasms/*genetics ; Nerve Tissue Proteins/genetics/metabolism/*physiology

OBJECTIVETo explore action mechanism of electroacupuncture (EA) on treatment of Parkinson's disease (PD).

METHODSA total of 40 healthy male SD rats were randomly divided into a normal group, a sham operation group, a model group and an EA group, 10 rats in each group. PD rat model was duplicated by micro injection of 6-hydroxyl dopamine into right striatum of rats, and the rats in the sham operation group were treated with micro injection of 0. 9% NaCl. Rats in the normal group, model group and the sham operation group received no treatment; rats in the EA group were treated by EA at "Fengfu" (GV 16) and "Taichong" (LR 3) with continuous wave, 2 Hz in frequency, 1 mA in intensity for 30 min. The treatment was given once a day for total 2 weeks. Behavioral test was used to evaluate rotational behavior changes of PD rats. RT-PCR method was applied to detect the expression of GFAP (glial fiber acidic protein) mRNA and Cx43 (connexin 43) mRNA in the striatum.

RESULTSThe difference of rotational behavior was not significant before and after treatment in the model group (P>0. 05), while that in the EA group was significant (P<0. 01). The expression of GFAP mRNA and Cx43 mRNA in the model group was significantly higher than that in the normal group and sham operation group (all P<0. 01); after EA treatment, the expression of GFAP mRNA and Cx43 mRNA in the EA group was lower significantly than that in the model group (both P<0. 01).

CONCLUSIONThe action mechanism of EA for prevention and treatment of Parkinson' s disease may be associated with inhibiting the activation of astrocytes.

Acupuncture Points ; Animals ; Astrocytes ; Connexin 43 ; genetics ; metabolism ; Corpus Striatum ; metabolism ; Electroacupuncture ; Humans ; Male ; Nerve Tissue Proteins ; genetics ; metabolism ; Parkinson Disease ; genetics ; metabolism ; therapy ; Rats ; Rats, Sprague-Dawley