Timely cell cycle regulation is conducted by sequential activation of a family of serine-threonine kinases called cycle dependent kinases (CDKs). Tight CDK regulation involves cyclin dependent kinase inhibitors (CKIs) which ensure the correct timing of CDK activation in different phases of the cell cycle. One CKI of importance is p27(KIP1). The regulation and cellular localization of p27(KIP1) can result in biologically contradicting roles when found in the nucleus or cytoplasm of both normal and tumor cells. The p27(KIP1) protein is mainly regulated by proteasomal degradation and its downregulation is often correlated with poor prognosis in several types of human cancers. The protein can also be functionally inactivated by cytoplasmic localization or by phosphorylation. The p27(KIP1) protein is an unconventional tumor suppressor because mutation of its gene is extremely rare in tumors, implying the normal function of the protein is deranged during tumor development. While the tumor suppressor function is mediated by p27(KIP1)'s inhibitory interactions with the cyclin/CDK complexes, its oncogenic function is cyclin/CDK independent, and in many cases correlates with cytoplasmic localization. Here we review the basic features and novel aspects of the p27(KIP1) protein, which displays genetically separable tumor suppressing and oncogenic functions.
Animals ; Cyclin-Dependent Kinases/genetics/*metabolism ; Humans ; Intracellular Signaling Peptides and Proteins/genetics/*metabolism ; Mutation ; Neoplasms/genetics/*metabolism ; Phosphorylation/genetics ; Protein Transport/genetics ; Tumor Suppressor Proteins/genetics/*metabolism

AIMBy using of Escherichia coli DH5alpha to express GST-Ccd1 fusion protein and which was purified by affinity chromatographic separation. The purified target protein was used to immunize rabbits to prepare polyclonal antibody.

METHODSThe previously constructed recombinant prokaryotic expression vector pGEX-5X-1-Ccd1 was transformed into Escherichia coli DH5alpha and was induced to expression by IPTG. The recombinant target protein was expressed with soluble state in Escherichia coli expression system which was separated and purified by chromatographic column stuffed with glutathione Sepharose 4B. The prepared antigen was used to immunize rabbits to get anti-Ccd1 specific rabbit original polyclonal antibody.

RESULTSELISA data demonstrated that the antibody titer of the serum was up to 1:40 000. Immunohistochemistry analysis indicated that the "home-made" antibody had a specific interaction with Ccd1 protein and which could be used for extended experimental research.

CONCLUSIONThe anti-Ccd1 polyclonal antibody we had prepared had a high quality of potency and specificity. The antibody was demonstrated by experiments that which could totally fulfill the requirement of immunoblotting and immunohistochemistry study of Ccd1. The antibody provided an useful experimental tool to profoundly research the tissue expression profile, intercellular location and biological function of Ccd1.

Antibodies ; metabolism ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; genetics ; Glutathione Transferase ; genetics ; metabolism ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; isolation & purification

The expression of endothelial nitric oxide synthase traffic inducer (NOSTRIN) was examined in the umbilical vessels of the patients with pre-eclampsia (PE) to explore its possible role in the pathogenesis of PE. The NOSTRIN mRNA in umbilical tissues was determined by RT-PCR. The eNOS activity in umbilical vessels was spectrophotometrically detected. NO2-/NO3-, the stable metabolic end products of NO, was measured by using nitrate reductase. RT-PCR showed that the expression level of NOSTRIN was significantly higher in women with PE than in the normal group (P<0.01). The activity of eNOS was significantly decreased in PE group [(12.83+/-3.61) U/mg] than in normal group [(21.72+/-3.83) U/mg] (P<0.01). The level of NO2-/NO3- in PE patients (27.53+/-7.48) micromol/mg was significantly lower than that of normal group (54.27+/-9.53) micromol/mg (P<0.01). The significant negative correlation existed between the expression of NOSTRIN and the activity of eNOS in umbilical vessels of women with PE (r=-0.58, P<0.01). It was concluded that the level of NOSTRIN expression was increased in umbilical vessel of women with PE, indicating that it may be involved in the pathogenesis of PE.
Intracellular Signaling Peptides and Proteins/genetics ; Intracellular Signaling Peptides and Proteins/*metabolism ; Pre-Eclampsia/*enzymology ; Pre-Eclampsia/etiology ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; Umbilical Arteries/cytology ; Umbilical Arteries/*enzymology ; Umbilical Veins/cytology ; Umbilical Veins/*enzymology

This study was aimed to investigated the mRNA expression levels of Notch ligands- Delta-like-1 and Jagged-1 in bone marrow mesenchymal stem cells of patients with myelodysplastic syndrome (MDS), and to explore their relation with onset of MDS. Bone marrow mesenchymal stem cells of 38 patients with MDS and 16 normal subjects as control were collected to detect mRNA expression of Delta-like-1 and Jagged-1 by using real-time quantitative polymerase chain reaction. The results showed that the expression levels of Delta-like-1 and Jagged-1 in mesenchymal stem cells of MDS patients were significantly higher than that in normal controls (P < 0.05). According to WHO criteria, the mRNA expression of Delta-like-1 in RA/RAS, RCMD and RAEB groups were significantly higher than that in normal controls (P < 0.05), the mRNA expression of Jagged-1 in RAEB group was also significantly higher than that in normal controls (P < 0.05). The mRNA expression of Delta-like-1 was significantly correlated with the proportion of blasts in the bone marrow of MDS patients (r = 0.502, P < 0.05). The expression levels of Delta-like-1 and Jagged-1 in MDS patients with abnormal karyotypes were significantly higher than those in MDS patients with normal karyotypes (P < 0.05). The mRNA expression of Delta-like-1 in higher risk group according to International Prognostic Scoring System was significantly higher than that in lower risk group (P < 0.05), there was no significant difference in Jagged-1 expression levels between higher risk group and lower risk group (P > 0.05). It is concluded that the changes of Delta-like-1 and Jagged-1 expression level in MSC may play a role in the pathogenesis of myelodysplastic syndrome.
Calcium-Binding Proteins ; genetics ; Gene Expression Regulation, Neoplastic ; Humans ; Intercellular Signaling Peptides and Proteins ; genetics ; Intracellular Signaling Peptides and Proteins ; genetics ; Jagged-1 Protein ; Membrane Proteins ; genetics ; Mesenchymal Stromal Cells ; metabolism ; Myelodysplastic Syndromes ; genetics ; RNA, Messenger ; biosynthesis ; Serrate-Jagged Proteins

OBJECTIVETo investigate the role of iASPP as the target gene of miR-124a in neural development.

METHODSUsing the online bioinformatical tool (TargetScan) and by reviewing the relevant studies, we selected iASPP as the candidate target gene of miR-124a involved in early-stage neuronal differentiation. Luciferase reporter assay was used to verify the candidate gene. We transfected M17 cells with a miR-124a overexpression plasmid and detected the changes in the protein expression of iASPP using Western blotting. With retinoic acid-induced M17 cells as the neuronal differentiation model, the role of iASPP in early-stage neuronal differentiation was investigated by gene overexpression and gene interference techniques.

RESULTSmiR-124a inhibited the expression of iASPP in M17 cells by interacting with the 3'UTR of iASPP gene. miR-124a promoted neurite outgrowth of the cells, which was blocked by iASPP overexpression.

CONCLUSIONmiR-124a promotes neurite outgrowth of M17 cells by inhibiting iASPP expression.

3' Untranslated Regions ; Gene Expression ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; metabolism ; MicroRNAs ; genetics ; Neurites ; metabolism ; Repressor Proteins ; genetics ; metabolism ; Transfection

OBJECTIVETo investigate the effects of overexpression of second mitochondria-derived activator of caspases (Smac) gene on apoptosis of gastric cancer cells.

METHODSUnder the induction of liposome, MKN-45 cells were transfected by Smac gene and incubated with G418 for subclone selection. Reverse transcriptase-polymerase chain reaction and Western blot were used to determine cellular Smac gene expression. After induction of apoptosis by mitomycin (MMC), cell viabilities were analyzed using trypan blue stain. Apoptosis was measured by electronic microscopy, acridine orange-ethidium bromide fluorescent staining and in situ terminally labelled transferase technique (TUNEL). Western blot and colorimetry were used to assess cellular caspase-3 expression and its activity.

RESULTSThe Smac mRNA and protein levels in MKN-45/Smac subclone cells (subclone consistently expressing Smac gene) were significantly higher than those in MKN-45 (P < 0.01). When compared with those in MKN-45, cell viabilities of MKN-45/Smac were reduced by 10.0% to 30.8% (P < 0.01), after treatment with 10 microg/ml MMC for 6 to 24 hours. Some of the MKN-45/Smac cells showed characteristic morphologic changes of apoptosis, their apoptotic rate being increased by 21.2% (P < 0.01). After treatment with MMC, caspase-3 expression and its activity in MKN-45/Smac cells were significantly higher than those in MKN-45 (P < 0.01).

CONCLUSIONSOverexpression of Smac in gastric cancer cell line significantly improves expression and activity levels of caspase-3 after induction by MMC. Such apoptosis-inducing effect establishes a novel strategy for regulating the apoptosis activity of gastric cancer.

Apoptosis ; Caspase 3 ; metabolism ; Cell Line, Tumor ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; Mitochondrial Proteins ; biosynthesis ; genetics ; Mitomycin ; pharmacology ; RNA, Messenger ; biosynthesis ; genetics ; Stomach Neoplasms ; metabolism ; pathology ; Transfection

PURPOSE: As a membrane protein at the insertion site of the slit diaphragm (SD) complex in podocyte foot processes, podocin has been reported to act as a scaffolding protein required to maintain or regulate the structural integrity of the SD. In order to identify proteins that associate or interact with podocin, we screened a mouse kidney complementary DNA (cDNA) library using a yeast 2-hybrid system. MATERIALS AND METHODS: 1) The full-length cDNA of podocin from the mouse kidney was amplified by Polymerase Chain Reaction (PCR), 2) The PCR product was cloned into a pGBKT7 vector, pGBKT7-podocin, 3) After the pGBKT7-podocin was transformed into AH109, the AH109/pGBKT7-podocin product was obtained, 4) The mouse kidney cDNA library was transformed into the AH109/pGBKT7-podocin and screened by selection steps, 5) Next, twelve clones were cultured and isolated, 6) The yeast-purified plasmids were transformed into Escherichia coli (E. coli) by heat shock, and 7) To identify the activation domain (AD)/library inserts, we digested them with Him III, and the fragments were then sequenced. RESULTS: 12 positive clones that interacted with podocin were obtained by screening a mouse kidney cDNA library using pGBKT7-podocin. Among them, only 4 clones were found to function at the podocyte where podocin is present. CONCLUSION: Additional studies are needed to clarify the role and interaction with podocin and candidates.
Animals ; Cloning, Molecular ; Intracellular Signaling Peptides and Proteins/genetics/*metabolism ; Membrane Proteins/genetics/*metabolism ; Mice ; Polymerase Chain Reaction ; Protein Binding ; *Two-Hybrid System Techniques

Branchio-oto syndrome (BOS)/branchio-oto-renal syndrome (BORS) is a kind of autosomal dominant heterogeneous disorder. These diseases are mainly characterized by hearing impairment and abnormal phenotype of ears, accompanied by renal malformation and branchial cleft anomalies including cyst or fistula, with an incidence of 1/40 000 in human population. Otic anormalies are one of the most obvious clinical manifestations of BOS/BORS, including deformities of external, middle, inner ears and hearing loss with conductive, sensorineural or mix, ranging from mild to profound loss. Temporal bone imaging could assist in the diagnosis of middle ear and inner ear malformations for clinicians. Multiple methods including direct sequencing combined with next generation sequencing (NGS), multiplex ligation-dependent probe amplification (MLPA), or array-based comparative genomic hybridization (aCGH) can effectively screen and identify pathogenic genes and/or variation types of BOS/BORS. About 40% of patients with BOS/BORS carry aberrations of EYA1 gene which is the most important cause of BOS/BORS. A total of 240 kinds of pathogenic variations of EYA1 have been reported in different populations so far, including frameshift, nonsense, missense, aberrant splicing, deletion and complex rearrangements. Human Endogenous Retroviral sequences (HERVs) may play an important role in mediating EYA1 chromosomal fragment deletion mutations caused by non-allelic homologous recombination. EYA1 encodes a phosphatase-transactivator cooperated with transcription factors of SIX1, participates in cranial sensory neurogenesis and development of branchial arch-derived organs, then regulates the morphological and functional differentiation of the outer ear, middle ear and inner ear toward normal tissues. In addition, pathogenic mutations of SIX1 and SIX5 genes can also cause BOS/BORS. Variations of these genes mentioned above may cause disease by destroying the bindings between SIX1-EYA1, SIX5-EYA1 or SIX1-DNA. However, the role of SIX5 gene in the pathogenesis of BORS needs further verification.
Branchio-Oto-Renal Syndrome/pathology* ; Chromosome Deletion ; Comparative Genomic Hybridization ; Genetic Research ; Homeodomain Proteins/genetics* ; Humans ; Intracellular Signaling Peptides and Proteins ; Nuclear Proteins/metabolism* ; Pedigree ; Protein Tyrosine Phosphatases/metabolism*

The NOD like receptors (NLRs), a class of intracellular receptors that respond to pathogen attack or cellular stress, have gained increasing attention. NLRC5, the largest member of the NLR protein family, has recently been identified as a critical regulator of immune responses. While NLRC5 is constitutively and widely expressed, it can be dramatically induced by interferons during pathogen infections. Both in vitro and in vivo studies have demonstrated that NLRC5 is a specific and master regulator of major mistocompatibility complex (MHC) class I genes as well as related genes involved in MHC class I antigen presentation. The expression of MHC class I genes is regulated by NLRC5 in coordination with the RFX components through an enhanceosome-dependent manner. And the involvement of NLRC5 in MHC class I mediated CD8+ T cell activation, proliferation and cytotoxicity is proved to be critical for host defense against intracellular bacterial infections. Nevertheless, the role of NLRC5 in innate immunity remains to be further explored. Here, we review the research advances on the structure, expression regulation and function of NLRC5.
Animals ; CD8-Positive T-Lymphocytes ; immunology ; metabolism ; Histocompatibility Antigens Class I ; genetics ; metabolism ; Humans ; Immunity, Innate ; Intracellular Signaling Peptides and Proteins ; chemistry ; genetics ; metabolism

OBJECTIVE: To explore the role of apoptosis stimulating proteins of p53 2 (ASPP2) and inhibitory member of the ASPP family (iASPP) in the occurrence of cervical cancer and the relation between these two proteins and p53. METHODS: We used immunohistochemical method to detect the expression of ASPP2, iASPP, p53 in 51 patients with early cervical cancer tissue, 53 patients with cervical intraepithelial neoplasia (CIN) II-III, 48 patients with CIN I and 45 patients with normal cervical tissue. The relation among ASPP2, iASPP and p53 was analyzed. RESULTS: When p53 was negative, the positive expression rate of ASPP2 in the cervical cancer group, the CIN II-III group, the CIN I group and the normal cervix group was gradually increased. There was significant difference between the CIN II-III group or the cervical cancer group and the normal cervix (P<0.05), but no statistical difference was found among the other groups (P>0.05). The positive expression rate of iASPP in the 4 groups gradually reduced, and the difference was significant difference between the cervical cancer group or the CIN II-III group and the normal cervix group (P<0.05). When the p53 was positive, there was no significant change in the expression of ASPP2 and iASPP in every group (P>0.05). CONCLUSION ASPP2 and iASPP may play an important role in the occurrence of early stage of cervical cancer by regulating the ability of wild type p53 in induction of apoptosis. ASPP2 and iASPP gene might be a potential molecular target for cervical carcinoma.
Apoptosis ; Apoptosis Regulatory Proteins ; genetics ; metabolism ; Cervical Intraepithelial Neoplasia ; genetics ; metabolism ; Female ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; metabolism ; Repressor Proteins ; genetics ; metabolism ; Tumor Suppressor Protein p53 ; genetics ; metabolism ; Uterine Cervical Neoplasms ; genetics ; metabolism