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Rich Protein (rich + protein)
Selected AbstractsRECK expression in osteosarcoma: correlation with matrix metalloproteinases activation and tumor invasivenessJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2007Hyun-Guy Kang Abstract Osteosarcoma is a malignant tumor of bone characterized by its high metastatic potential. For the development of metastasis, activation of matrix metalloproteinases (MMPs) is required. A novel MMPs inhibitor, reversion inducing cysteine rich protein with Kazal motifs (RECK), is known to down-regulate MMPs and suppress the invasive and metastatic potential in many tumor-derived cell lines and some types of tumors. The expression of RECK and its role in tumor invasiveness have never been studied in osteosarcoma. We examined RECK mRNA expression and MMPs activation in osteosarcoma using quantitative real time PCR, gelatin zymography, invasion assay, and transfection experiments. RECK was expressed but down-regulated in osteosarcoma cells. Activation of pro-MMP-2 was observed in all samples, whereas activation of MMP-2 and pro-MMP-9 was detected in only 11% and 7% of the samples, respectively. MMP-9 was not activated in any of the samples. The level of RECK expression was inversely correlated with pro-MMP-2 activation, and overexpression of RECK by transfection resulted in decreased pro-MMP-2 activation and reduced tumor invasiveness. These findings suggest that RECK plays an important role in the invasiveness of osteosarcoma. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:696,702, 2007 [source] NSSR1 is regulated in testes development and cryptorchidism and promotes the exon 5-included splicing of CREB transcriptsMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 11 2007Ping-Jie Xiao Abstract Neural salient serine/arginine rich protein 1 (NSSR1, alternatively SRp38) is a newly identified splicing factor that is highly expressed in neural and reproductive tissues. We showed that the expression of testicular NSSR1 increased significantly during mouse testes development. NSSR1 was mainly expressed in germ cells, but barely detected in Sertoli cells. Testicular NSSR1 was mostly phosphorylated and cytosolic in germ cells. In comparison, pituitary NSSR1 was mostly dephosphorylated and nuclear. In the cryptorchid testes, the dephosphorylated NSSR1 was significantly increased. RT-PCR analysis demonstrated that the alternative splicing of CREB and CREM genes was altered in the cryptorchid testes. In addition, CREB transcripts were associated with NSSR1 either in testes tissues or cultured GC-1 cells. Moreover, the studies with NSSR1 over-expression or silence demonstrated that NSSR1 promoted the exon 5 inclusion of CREB, indicating that NSSR1 is a new factor that regulates the alternative exon 5 inclusion of CREB transcripts. The findings for the first time provide the evidence indicating the potential importance of NSSR1 in testes development, spermatogenesis and cryptorchidism. Mol. Reprod. Dev. 74: 1363,1372, 2007. © 2007 Wiley-Liss, Inc. [source] Disease stress-inducible genes of tobacco: expression profile of elicitor-responsive genes isolated by subtractive hybridizationPHYSIOLOGIA PLANTARUM, Issue 4 2003Daigo Takemoto In order to investigate the change in mRNA profile during tobacco disease response, a subtractive hybridization procedure was used to generate a cDNA library for genes induced in tobacco (Nicotiana tabacum cv. Samsun NN) treated with oomycete elicitor. Database searches with the randomly isolated genes revealed that this cDNA library was enriched for reported disease stress-responsive genes such as pathogenesis-related proteins and cell wall protein genes. The expressions of eight newly isolated genes were induced by inoculation with the non-pathogenic bacteria, Pseudomonas syringae pv. glycinea. The NtEIGs (N.tabacumelicitor- inducible genes) showed similarity to genes for stellacyanin-like protein (NtEIG-A1), glutathione peroxidase (NtEIG-C08), extensin-like protein (NtEIG-C29), WRKY transcription factor (NtEIG-D48), glycine rich protein (NtEIG-E17), , -1, 3-glucanase-like protein (NtEIG-E76), photoassimilate-responsive protein-1 (NtEIG-E80) and wound-induced protein (NtEIG-D10). The expression patterns of NtEIGs in tobacco leaf in response to P. syringae pv. glycinea, salicylic acid (SA), methyl jasmonate (MeJA) and wound stress were analysed. The individual expression patterns of NtEIGs indicate that the transcriptional activation of NtEIGs is regulated by various signals and the products of NtEIGs are involved in different processes at different stages of the plant defence responses. [source] Proteome mapping of overexpressed membrane-enriched and cytosolic proteins in sodium antimony gluconate (SAG) resistant clinical isolate of Leishmania donovaniBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 4 2010Awanish Kumar WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Over 60% of patients with visceral leishmaniasis (VL) in India and Sudan have become unresponsive to treatment with pentavalent antimonials, the first line of drugs for over 60 years. The drug resistance mechanism, studied so far in in vitro selected laboratory strains, has been attributed to various biochemical parameters. The resistance to Sb (V) in Leishmania field isolates is still unexplored. WHAT THIS STUDY ADDS In order to elucidate for the first time the mechanism of drug resistance in field isolates, this study was done in those clinically relevant field isolates which were either responsive or non responsive to SAG. A comparison of proteome profiles of membrane-enriched as well as cytosolic protein fractions of these isolates has pinpointed the multiple overexpressed proteins in resistant isolates. This study has indicated their possible essential role in antimony resistance of the parasite and provides a vast field to be exploited to find much needed novel treatment strategies against VL. AIMS This study aimed to identify differentially overexpressed membrane-enriched as well as cytosolic proteins in SAG sensitive and resistant clinical strains of L. donovani isolated from VL patients which are involved in the drug resistance mechanism. METHODS The proteins in the membrane-enriched as well as cytosolic fractions of drug-sensitive as well as drug-resistant clinical isolates were separated using two-dimensional gel electrophoresis and overexpressed identified protein spots of interest were excised and analysed using MALDI-TOF/TOF. RESULTS Six out of 12 overexpressed proteins were identified in the membrane-enriched fraction of the SAG resistant strain of L. donovani whereas 14 out of 18 spots were identified in the cytosolic fraction as compared with the SAG sensitive strain. The major proteins in the membrane-enriched fraction were ABC transporter, HSP-83, GPI protein transamidase, cysteine,leucine rich protein and 60S ribosomal protein L23a whereas in the cytosolic fraction proliferative cell nuclear antigen (PCNA), proteasome alpha 5 subunit, carboxypeptidase, HSP-70, enolase, fructose-1,6-bisphosphate aldolase, tubulin-beta chain have been identified. Most of these proteins have been reported as potential drug targets, except 60S ribosomal protein L23a and PCNA which have not been reported to date for their possible involvement in drug resistance against VL. CONCLUSION This study for the first time provided a cumulative proteomic analysis of proteins overexpressed in drug resistant clinical isolates of L. donovani indicating their possible role in antimony resistance of the parasite. Identified proteins provide a vast field to be exploited for novel treatment strategies against VL such as cloning and overexpression of these targets to produce recombinant therapeutic/prophylactic proteins. [source] Structural composition of ,I - and ,II -proteinsPROTEIN SCIENCE, Issue 2 2003Narasimha Sreerama Abstract Circular dichroism spectra of proteins are sensitive to protein secondary structure. The CD spectra of ,-rich proteins are similar to those of model ,-helices, but ,-rich proteins exhibit CD spectra that are reminiscent of CD spectra of either model ,-sheets or unordered polypeptides. The existence of these two types of CD spectra for ,-rich proteins form the basis for their classification as ,I - and ,II -proteins. Although the conformation of ,-sheets is largely responsible for the CD spectra of ,I -proteins, the source of ,II -protein CD, which resembles that of unordered polypeptides, is not completely understood. The CD spectra of unordered polypeptides are similar to that of the poly(Pro)II helix, and the poly(Pro)II-type (P2) structure forms a significant fraction of the unordered conformation in globular proteins. We have compared the ,-sheet and P2 structure contents in ,-rich proteins to understand the origin of ,II -protein CD. We find that ,II -proteins have a ratio of P2 to ,-sheet content greater than 0.4, whereas for ,I -proteins this ratio is less than 0.4. The ,-sheet content in ,I -proteins is generally higher than that in ,II -proteins. The origin of two classes of CD spectra for ,-rich proteins appears to lie in their relative ,-sheet and P2 structure contents. [source] Proteomic analysis of conjucntival swab by mass spectrometryACTA OPHTHALMOLOGICA, Issue 2007V MCGILLIGAN Purpose: The purpose of this study was to identify proteins present in the tears and mucosal epithelium of the ocular surface. Methods: A cotton swab was rubbed across the anaesthetized inferior conjunctiva of a dry eye patient. Protein was extracted and subjected to 1D gel electrophoresis. After excision and trypsinisation, protein profiles from swab samples were identified using mass spectrometry carried out on a 3200 Q-TRAP Hybrid ESI Quadropole linear ion trap. Protein identification was performed using MASCOT software against a human database extracted from NCBI. Curation of the protein list was achieved using the bioinformatics tool PROVALT, which also calculated false-discovery rates. Results: In total 75 validated proteins were identified including the tear proteins, lactotransferrin, lysozyme, and proline rich proteins as well as a number of proteins not previously associated with the tear proteome. Proteins identified had a wide range of physio-chemical properties and included structural and functional proteins. Conclusions: Use of a simple swab combined with a GeLC-MS proteomic protocol led to unequivocal identification of a large range of proteins associated with the ocular surface proteome. This may allow a better characterisation of the ocular surface environment and discrimination between various eye conditions. Tear collection using capillaries can be tedious and may discourage clinicians from performing such a test. Use of a swab that can be frozen for analysis may encourage the use of this methodology. Analysis of this proteome offers huge clinical potential for investigation of ocular surface biomarkers for the development of novel diagnostic tools and monitoring of ocular disease. [source] | |||||||||||||