OBJECTIVE: The etiology of attention deficit hyperactivity disorder (ADHD) has not been entirely clarified yet. Structural and metabolic differences at the prefrontal striatal cerebellary system and the interaction of gene and environment are the main factors that thought to play roles in the etiology. Genetic investigations are performed especially about the dopamine pathways and receptors. In this study; it was aimed to investigate the association of the synaptobrevin-2 (VAMP-2) gene Ins/Del polymorphism and syntaxin 1A gene intron 7 polymorphism, which take place in encoding presynaptic protein, with adult ADHD. METHODS: One hundred thirty-nine patients, having ADHD aging between 18 and 60 years and 106 healthy people as controls were included into the study. DNA samples were extracted from whole blood and genetic analysis were performed. RESULTS: A significant difference was determined between ADHD and VAMP-2 Ins/Del polymorphism and syntaxin 1A intron 7 polymorphism according to the control group. These polymorphisms were found not to be associated with subtypes of ADHD. CONCLUSION: It is supposed that synaptic protein genes together with dopaminergic genes might have roles in the etiology of ADHD.
Adult* ; Aging ; Attention Deficit Disorder with Hyperactivity* ; DNA ; Dopamine ; Humans ; Introns ; Qa-SNARE Proteins* ; Syntaxin 1* ; Vesicle-Associated Membrane Protein 2*

One of the major circulatory changes that occur in human during space flight and simulated weightlessness is a cerebral redistribution of body fluids, which is accompanied by an increase of blood volume in the upper body. Therefore, atrial myocardium should increase the secretion of atrial natriuretic peptide (ANP), but the researches lack common conclusion until now. The present study was to investigate the expression level of ANP in simulated weightlessness rats, and to confirm the changes of ANP by observing the associated proteins of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs). The tail-suspended rat model was used to simulate weightlessness. Western blots were carried out to examine the expression levels of ANP and SNARE proteins in atrial and left ventricular myocardium. The results showed that ANP expression in atrial myocardium showed an increase in 4-week tail-suspended rats (SUS) compared with that in the synchronous control rats (CON). We only detected a trace amount of ANP in the left ventricular myocardium of the CON, but found an enhanced expression of ANP in left ventricular myocardium of the SUS. Expression of VAMP-1/2 (vesicle associated SNARE) increased significantly in both atrial and left ventricular myocardium in the SUS compared with that in the CON. There was no difference of the expression of syntaxin-4 (target compartment associated SNARE) between the CON and SUS, but the expression of SNAP-23 showed an increase in atrial myocardium of the SUS compared with that in the CON. Synip and Munc-18c as regulators of SNAREs did not show significant difference between the CON and SUS. These results suggest that the expression of ANP shows an increase in atrial and left ventricular myocardium of 4-week tail-suspended rats. Enhanced expression of VAMP-1/2 associated with ANP vesicles confirms the increased expression of ANP in atrial and left ventricular myocardium.
Animals ; Atrial Natriuretic Factor ; metabolism ; Heart Ventricles ; metabolism ; Myocardium ; metabolism ; Rats ; SNARE Proteins ; metabolism ; Vesicle-Associated Membrane Protein 1 ; metabolism ; Vesicle-Associated Membrane Protein 2 ; metabolism ; Weightlessness Simulation

Leucine-rich repeat kinase 2 (LRRK2) is a gene that, upon mutation, causes autosomal-dominant familial Parkinson's disease (PD). Yeast two-hybrid screening revealed that Snapin, a SNAP-25 (synaptosomal-associated protein-25) interacting protein, interacts with LRRK2. An in vitro kinase assay exhibited that Snapin is phosphorylated by LRRK2. A glutathione-S-transferase (GST) pull-down assay showed that LRRK2 may interact with Snapin via its Ras-of-complex (ROC) and N-terminal domains, with no significant difference on interaction of Snapin with LRRK2 wild type (WT) or its pathogenic mutants. Further analysis by mutation study revealed that Threonine 117 of Snapin is one of the sites phosphorylated by LRRK2. Furthermore, a Snapin T117D phosphomimetic mutant decreased its interaction with SNAP-25 in the GST pull-down assay. SNAP-25 is a component of the SNARE (Soluble NSF Attachment protein REceptor) complex and is critical for the exocytosis of synaptic vesicles. Incubation of rat brain lysate with recombinant Snapin T117D, but not WT, protein caused decreased interaction of synaptotagmin with the SNARE complex based on a co-immunoprecipitation assay. We further found that LRRK2-dependent phosphorylation of Snapin in the hippocampal neurons resulted in a decrease in the number of readily releasable vesicles and the extent of exocytotic release. Combined, these data suggest that LRRK2 may regulate neurotransmitter release via control of Snapin function by inhibitory phosphorylation.
Amino Acid Sequence ; Animals ; Exocytosis ; Female ; HEK293 Cells ; Humans ; Mice ; Molecular Sequence Data ; Mutant Proteins/metabolism ; Phosphorylation ; Phosphothreonine/metabolism ; Protein Binding ; Protein Interaction Mapping ; Protein Structure, Tertiary ; Protein-Serine-Threonine Kinases/*metabolism ; Qa-SNARE Proteins/metabolism ; Rats ; Rats, Sprague-Dawley ; Synaptosomal-Associated Protein 25/*metabolism ; Synaptotagmins/metabolism ; Vesicle-Associated Membrane Protein 2/metabolism ; Vesicular Transport Proteins/chemistry/*metabolism

Semenogelin I (Sg I) and the fragments of peptides hydrolyzed from Sg I by prostate-specific antigen have multiple biological activities. There exists a controversy over the inhibitory effect of the key fragment on sperm motility. This article focuses on the sperm-inhibiting and antibacterial activities of the fragments of Sg I-derived peptides and illustrates the supposition concerning the most controversial aspect. A deeper insight into the action mechanisms of Sg I-derived peptides may help improve the methods of sperm screening and provide a new perspective in the management of asthenozoospermia and urinary tract infection.
Anti-Bacterial Agents ; Humans ; Male ; Semen ; drug effects ; Seminal Vesicle Secretory Proteins ; genetics ; physiology ; Spermatozoa ; drug effects

Animals ; Exocytosis ; drug effects ; physiology ; Glucose ; pharmacology ; Insulin ; secretion ; Insulin-Secreting Cells ; cytology ; drug effects ; metabolism ; Mice ; Microscopy, Fluorescence ; methods ; Potassium ; pharmacology ; Recombinant Fusion Proteins ; genetics ; metabolism ; Vesicle-Associated Membrane Protein 2 ; genetics ; metabolism

Semen liquefaction and sperm capacitation are the key processes for sperm to acquire forward movement ability. In these processes, semenogelin plays a vital role by directly participating in the formation of semen coagulation, collaborating with other protease and metal ions from the male reproductive tract, and then reacting with the surface of sperm cells, finally involved in the regulation of these processes and ensuring sperm's acquisition of forward movement ability.
Humans ; Male ; Semen ; chemistry ; Seminal Vesicle Secretory Proteins ; physiology ; Sperm Motility

Sperm acquires capacity of motility and fertility during the process of semen coagulation and liquefaction. The main coagulative protein is Semenogelin I (Sg I), specifically produced by seminal vesicles, and then decomposed by prostate specific antigens (PSA) in sperm liquefaction into a series of small fragments. These fragments, with a variety of physiological functions, are very important for the regulation of sperm capacity acquisition and progressive movement.
Humans ; Male ; Seminal Vesicle Secretory Proteins ; physiology ; Seminal Vesicles ; metabolism ; physiology

AIMTo study the molecular mechanism of epididymal protease inhibitor (Eppin) modulating the process of prostate specific antigen (PSA) digesting semenogelin (Sg).

METHODSHuman Sg cDNA (nucleotides 82-849) and Eppin cDNA (nucleotides 70-723) were generated by polymerase chain reaction (PCR) and cloned into pET-100D/TOPO. Recombinant Eppin and Sg (rEppin and rSg) were produced by BL21 (DE3). The association of Eppin with Sg was studied by far-western immunoblot and radioautography. In vitro the digestion of rSg by PSA in the presence or absence of rEppin was studied. The effect of anti-Q20E (N-terminal) and C-terminal of Eppin on Eppin-Sg binding was monitored.

RESULTSEppin binds Sg on the surface of human spermatozoa with the C-terminal of Eppin (amino acids 75-133). rSg was digested with PSA and many low molecular weight fragments were produced. When rEppin is bound to rSg, then digested by PSA, incomplete digestion and a 15-kDa fragment results. Antibody binding to the N-terminal of rEppin did not affect rSg digestion. Addition of antibodies to the C-terminal of rEppin inhibited the modulating effect of rEppin.

CONCLUSIONEppin protects a 15-kDa fragment of rSg from hydrolysis by PSA.

Animals ; Antibodies ; pharmacology ; Autoradiography ; Humans ; Hydrolysis ; Male ; Prostate-Specific Antigen ; metabolism ; Proteinase Inhibitory Proteins, Secretory ; genetics ; immunology ; metabolism ; Rabbits ; Recombinant Proteins ; genetics ; metabolism ; Semen ; cytology ; metabolism ; Seminal Vesicle Secretory Proteins ; metabolism ; Spermatozoa ; metabolism

We have previously shown that seminal vesicle protein IV (SV-IV) and its 1-70 N-terminal fragment have anti-inflammatory activity and modulate anti-thrombin III (AT) activity. Moreover, mass spectrometry analysis of purified SV-IV has shown that the protein was found to be highly heterogeneous and 14% of the total SV-IV molecules are truncated forms, of particular interest the 1-16, 1-17, and 1-18 peptides. In this work we report experimental data which demonstrate that the 1-16 peptide (P1-16) possesses a marked effect on the AT activity by preventing the formation of the thrombin-AT complex. We found that the formation of thrombin-AT complex is markedly decreased in the presence of P1-16 used at equimolar concentration with thrombin as evaluated with SDS-PAGE. We also monitored the conformational changes of thrombin in the presence of different P1-16 concentrations, and calculated the K(d) of thrombin/P1-16 system by circular dichroism technique. The probable interaction sites of P1-16 with thrombin have been also evaluated by molecular graphics and computational analyses. These results have potential implications in the treatment of sterility and thrombotic diseases.
Amino Acid Sequence ; Animals ; Antithrombin III/metabolism ; Blood Coagulation/drug effects ; Circular Dichroism ; Humans ; Models, Molecular ; Molecular Sequence Data ; Peptide Fragments/*chemistry/pharmacology ; Protein Binding/drug effects ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Rats ; Seminal Vesicle Secretory Proteins/*chemistry/genetics/metabolism ; Thrombin/*chemistry/genetics/metabolism

OBJECTIVETo produce recombinant human prostate-specific antigen (PSA) by molecular cloning technology and to identify its activity.

METHODSThe human PSA cDNA and PET-12a vector were digested by NdeI and BamH1 before ligated by T4 ligase. The correct sequence was verified and transformed into high competent E. coli BL21 (DE3). Recombinant PSA was expressed and purified by hydrophobic interaction phenyl Sepharose column and activated by trypsin digestion. Enzymatic activation assay was done by hydrolysis of the substrate S-2586 and semenogelin.

RESULTSNon-active recombinant PSA was digested by trypsin and demonstrated enzyme activity. The activated PSA hydrolyzed S-2586 and its physiological substrate semenogelin (Sg).

CONCLUSIONRecombinant pro-PSA can be an active serine protease by trypsin digestion and demonstrate native PSA enzymatic activity.

Blotting, Western ; Cloning, Molecular ; DNA, Complementary ; genetics ; Escherichia coli ; genetics ; Gene Expression ; Humans ; Hydrolysis ; Male ; Oligopeptides ; metabolism ; Prostate-Specific Antigen ; genetics ; isolation & purification ; metabolism ; Recombinant Proteins ; isolation & purification ; metabolism ; Seminal Vesicle Secretory Proteins ; metabolism ; Trypsin ; metabolism