Specific Proteins in the Indirect Somatic Embryogenesis of Freesia Refracta

Using the young inflorescence segments of Freesia refracta as explants, indirect somatic embryogenesis of somatic cells was induced in a N6 medium supplemented with some exogenous hormones. SDS-polyacrylamide gel electrophoresis（SDS-PAGE） was used for the analysis of soluble proteins produced during the somatic embryogenesis of this plant. There are six polypeptides, which might play some roles in the process of somatic embryo development. Tltree polypeptides（45, 53 and 55 kD） were detected in the stages of embryogenic callus, globular embryoid, and embryoid with coleoptiles, except the embryoid with leaf. One polypeptide（ 83 kD） was specific for the stages of embryoid with eoleoptiles and embryoid with leaf. One polypeptide（37 kD） was detected in the first two stages, namely, embryogenic callus and globular embryoid. One polypeptide（35 kD） was regularly synthesized in each stage, from embryogenic callus to embryoid with leaf.

Preliminary Identification of Human Nonserum Oviduct Specific Proteins by Using Electrophoresis and Immunoblotting Analysis

The present paper reported the preliminary results of identification of humannonserum oviduct specific proteins. The 1D-SDS-polyacrylamide gel electrophoresis (PAGE) and 2D-SDS-PAFE in conjunction with the immunoblotting assay were used in the present study. The results showed that the nonserum oviduct specific proteins with MW130, 100 and 80 kD existed in human oviduct fluid or oviductal extract. In addition, the antibody against pig oviduct antigens could more strongly cross-react with human oviduct antigens, mainly recognizing 130,116 and 100 kD proteins from human oviduct. It is suggested that in human oviduct there are some specific antigens possessing some similar epitopes to those in pig oviducts. This result seems to be consistent with predominant cross reactivity existing in antigens of porcine and human zona pellucida.

A SPECIFIC PROTEIN FOUND IN HUMAN SENESCENT FIBROBLASTS

The limited potential for proliferation of human fibroblasts in culture represents cell level senescence. Aging is a programed process under generic control, and at certain stage of the life-span of animal cells, some genes start to express. Studying the biomarkers of senescent cells is important to understanding the basic mechanism of aging which may be relevant to the normal cell growth control and tumor biology. A protein with 72 000 Dalton molecular weight was detected by the hybridoma method in our laborotary. The protein shows specificity to senescent or presenescent cells of several cell lines, including WI-38, K.D., U2OS, etc.

Expression and role of specificity protein 1 in the sclera remodeling of experimental myopia in guinea pigs

AIM：To study the expression of collagen I and transcription factor specificity protein 1（Sp1）,a transforming growth factor-β1（TGF-β1） downstream target,and reveal the impact of the TGF-β1-Sp1 signaling pathway on collagen remodeling in myopic sclera.METHODS：Seventy-five 1-week-old guinea pigs were randomly divided into normal control,form deprivation myopia（FDM）,and self-control groups.FDM was induced for different times using coverage with translucent latex balloons and FDM recovery was performed for 1wk after 4wk treatment;then,changes in refractive power and axial length were measured.Immunohistochemistry and reverse transcription-polymerase chain reaction were used to evaluate dynamic changes in collagen I and Sp1 expression in the sclera of guinea pigs with emmetropia and experimental myopia,and the relationship between collagen I and Sp1 levels was analyzed.RESULTS：In the FDM group,the refractive power was gradually changed（from 2.09±0.30 D at week 0 to-1.23±0.69 D,-4.17±0.59 D,-7.07±0.56 D,and-4.30±0.58 D at weeks 2,4,6,and 1wk after 4wk,respectively;P〈0.05）,indicating deepening of myopia.The axial length was increased（from 5.92±0.39 mm at week 0 to 6.62±0.36 mm,7.30±0.34 mm,7.99±0.32 mm,and 7.41±0.36 mm at weeks 2,4,6,and 1wk after 4wk;P〈0.05）.The m RNA and protein expression of Sp1 and collagen I in the sclera of the FDM group was lower than that of the control groups（P〈0.05）,and the reduction was eye-coverage time-dependent.Furthermore,correlation between Sp1 and collagen I down-regulation in the myopic sclera was observed.CONCLUSION：Our data indicate that transcription factor Sp1 may be involved in the regulation of type I collagensynthesis/degradation during myopic sclera remodeling,suggesting that TGF-β1 signaling plays a role in the development and progression of myopia.

Transcription factors specificity protein and nuclear receptor 4A1 in pancreatic cancer

Specificity protein(Sp)transcription factors(TFs)Sp1,Sp3 and Sp4,and the orphan nuclear receptor 4A1(NR4A1)are highly expressed in pancreatic tumors and Sp1 is a negative prognostic factor for pancreatic cancer patient survival.Results of knockdown and overexpression of Sp1,Sp3 and Sp4 in pancreatic and other cancer lines show that these TFs are individually pro-oncogenic factors and loss of one Sp TF is not compensated by other members.NR4A1 is also a prooncogenic factor and both NR4A1 and Sp TFs exhibit similar functions in pancreatic cancer cells and regulate cell growth,survival,migration and invasion.There is also evidence that Sp TFs and NR4A1 regulate some of the same genes including survivin,epidermal growth factor receptor,PAX3-FOXO1,α5-andα6-integrins,β1-,β3-andβ4-integrins;this is due to NR4A1 acting as a cofactor and mediating NR4A1/Sp1/4-regulated gene expression through GC-rich gene promoter sites.Several studies show that drugs targeting Sp downregulation or NR4A1 antagonists are highly effective inhibitors of Sp/NR4A1-regulated pathways and genes in pancreatic and other cancer cells,and the triterpenoid celastrol is a novel dual-acting agent that targets both Sp TFs and NR4A1.

Expression and role of specificity protein 1 and collagenⅠin recurrent pterygial tissues

AIM:To investigate the expression profiles of the transcription factor specificity protein 1(Sp1)and collagenⅠin recurrent pterygial tissues.What is more,to compare the changes of Sp1 and collagen I among primary pterygial tissue,recurrent pterygial tissue and conjunctival tissue.METHODS:In the prospective study,we collected the pterygial tissues of 40 patients who underwent resection of primary pterygial tissue and recurrent pterygial tissue,and the conjunctival tissues of 10 patients with enucleation due to trauma.The relative expression levels of Sp1 and collagen I were analyzed by reverse transcription quantitative-polymerase chain reaction and Western blot.Paired t-test was performed to compare the Sp1 and collagen I of recurrent pterygial tissues,as well as the primary pterygial tissues and conjunctival tissues.In further,Pearson’s hypothesis testing of correlation coefficients was used to compare the correlations of Sp1 and Collagen I.RESULTS:The content of Sp1 and collagen I m RNA and protein was significantly greater in recurrent pterygial tissue than that was in primary and conjunctival tissue(P<0.05).There was a positive correlation between the m RNA and protein levels of Sp1 and collagen I in recurrent pterygial tissues(protein:r=0.913,P<0.05;m RNA:r=0.945,P<0.05).CONCLUSION:Sp1 and collagen I are expressed in normal conjunctival,primary,and recurrent pterygial tissues,but expression is significantly greater in the latter.Sp1 and collagen I may be involved in the regulation of the development of recurrent pterygium.

Upregulated lncRNA PRNT promotes progression and oxaliplatin resistance of colorectal cancer cells by regulating HIPK2 transcription

BACKGROUND Colorectal cancer(CRC)is the third most common cancer and a significant cause of cancer-related mortality globally.Resistance to chemotherapy,especially during CRC treatment,leads to reduced effectiveness of drugs and poor patient outcomes.Long noncoding RNAs(lncRNAs)have been implicated in various pathophysiological processes of tumor cells,including chemotherapy resistance,yet the roles of many lncRNAs in CRC remain unclear.AIM To identify and analyze the lncRNAs involved in oxaliplatin resistance in CRC and to understand the underlying molecular mechanisms influencing this resistance.METHODS Gene Expression Omnibus datasets GSE42387 and GSE30011 were reanalyzed to identify lncRNAs and mRNAs associated with oxaliplatin resistance.Various bioinformatics tools were employed to elucidate molecular mechanisms.The expression levels of lncRNAs and mRNAs were assessed via quantitative reverse transcription-polymerase chain reaction.Functional assays,including MTT,wound healing,and Transwell,were conducted to investigate the functional implications of lncRNA alterations.Interactions between lncRNAs and trans-cription factors were examined using RIP and luciferase reporter assays,while Western blotting was used to confirm downstream pathways.Additionally,a xenograft mouse model was utilized to study the in vivo effects of lncRNAs on chemotherapy resistance.RESULTS LncRNA prion protein testis specific(PRNT)was found to be upregulated in oxaliplatin-resistant CRC cell lines and negatively correlated with homeodomain interacting protein kinase 2(HIPK2)expression.PRNT was demonstrated to sponge transcription factor zinc finger protein 184(ZNF184),which in turn could regulate HIPK2 expression.Altered expression of PRNT influenced CRC cell sensitivity to oxaliplatin,with overexpression leading to decreased sensitivity and decreased expression reducing resistance.Both RIP and luciferase reporter assays indicated that ZNF184 and HIPK2 are targets of PRNT.The PRNT/ZNF184/HIPK2 axis was implicated in promoting CRC progression and oxaliplatin resistance both in vitro and in vivo.CONCLUSION The study concludes that PRNT is upregulated in oxaliplatin-resistant CRC cells and modulates the expression of HIPK2 by sponging ZNF184.This regulatory mechanism enhances CRC progression and resistance to oxaliplatin,positioning PRNT as a promising therapeutic target for CRC patients undergoing oxaliplatin-based chemotherapy.

Diagnosis of Tumor-Like Polypoid Lesions of Gallbladder by Serum Proteomic Fingerprint

Objective： To search the specific serum proteins in tumor-like polypoid lesions of the gallbladder（PLG） patients. Methods： Surface enhanced laser desorption/ionization time of flight mass spectrometry （SELDI-TOF-MS） technique and WCX Magnetic Beads were used to detect the serum proteomic fingerprint of 23 patients with tumor-like PLG, 21 patients with non tumor-like PLG and 26 normal persons. Biomarker Wizard and Biomarker Patterns Software were used in combination to analyze the data. Results： In the preliminary screening, 22 representative specific proteins for tumor-like PLG were found. Seven specific proteins showed increased expression and 15 specific proteins showed decreased expression in the tumor-like PLG patients. Three specific proteins are selected for the diagnosis of the tumor-like PLG.. Conclusion： SELDI-TOF-MS technique can be used to select specific proteins for tumor-like PLG patients, which may be useful for the diagnosis of the tumor-like PLG and the differential diagnosis with the non tumor-like PLG.

Sodium selenite promotes neurological function recovery after spinal cord injury by inhibiting ferroptosis

Ferroptosis is a recently discovered form of iron-dependent cell death,which occurs during the pathological process of various central nervous system diseases or injuries,including secondary spinal cord injury.Selenium has been shown to promote neurological function recovery after cerebral hemorrhage by inhibiting ferroptosis.However,whether selenium can promote neurological function recovery after spinal cord injury as well as the underlying mechanism remain poorly understood.In this study,we injected sodium selenite(3μL,2.5μM)into the injury site of a rat model of T10 vertebral contusion injury 10 minutes after spinal cord injury modeling.We found that sodium selenite treatment greatly decreased iron concentration and levels of the lipid peroxidation products malondialdehyde and 4-hydroxynonenal.Furthermore,sodium selenite increased the protein and mRNA expression of specificity protein 1 and glutathione peroxidase 4,promoted the survival of neurons and oligodendrocytes,inhibited the proliferation of astrocytes,and promoted the recovery of locomotive function of rats with spinal cord injury.These findings suggest that sodium selenite can improve the locomotive function of rats with spinal cord injury possibly through the inhibition of ferroptosis via the specificity protein 1/glutathione peroxidase 4 pathway.