MAB21L1 promotes survival of lens epithelial cells through control of αB-crystallin and ATR/CHK1/p53 pathway.

The male abnormal gene family 21 (), was initially identified in . Since its identification, studies from different groups have shown that it regulates development of ocular tissues, brain, heart and liver. However, its functional mechanism remains largely unknown.

MYPT1/PP1-Mediated EZH2 Dephosphorylation at S21 Promotes Epithelial-Mesenchymal Transition in Fibrosis through Control of Multiple Families of Genes.

The methyltransferase EZH2 plays an important role in regulating chromatin conformation and gene transcription. Phosphorylation of EZH2 at S21 by AKT kinase suppresses its function. However, protein phosphatases responsible for the dephosphorylation of EZH2-S21 remain elusive.

PP-1β and PP-2Aα modulate cAMP response element-binding protein (CREB) functions in aging control and stress response through de-regulation of αB-crystallin gene and p300-p53 signaling axis.

The function of the transcription factor, cAMP response element-binding protein (CREB), is activated through S133 phosphorylation by PKA and others. Regarding its inactivation, it is not well defined. cAMP response element-binding protein plays an essential role in promoting cell proliferation, neuronal survival and the synaptic plasticity associated with long-term memory.

Aging-dependent loss of GAP junction proteins Cx46 and Cx50 in the fiber cells of human and mouse lenses accounts for the diminished coupling conductance.

The homeostasis of the ocular lens is maintained by a microcirculation system propagated through gap junction channels. It is well established that the intercellular communications of the lens become deteriorative during aging. However, the molecular basis for this change in human lenses has not been well defined.

The E3 Ligase PIAS1 Regulates p53 Sumoylation to Control Stress-Induced Apoptosis of Lens Epithelial Cells Through the Proapoptotic Regulator Bax.

Protein sumoylation is one of the most important post-translational modifications regulating many biological processes (Flotho A & Melchior F. 2013. .

The transcription factor CREB acts as an important regulator mediating oxidative stress-induced apoptosis by suppressing αB-crystallin expression.

The general transcription factor, CREB has been shown to play an essential role in promoting cell proliferation, neuronal survival and synaptic plasticity in the nervous system. However, its function in stress response remains to be elusive. In the present study, we demonstrated that CREB plays a major role in mediating stress response.

Glucose Oxidase- and UVA-Induced Changes in the Expression Patterns of Seven De-sumoylation Enzymes (SENPs) Are Associated with Cataract Development.

Objective: It has been well established that sumoylation acts as an important regulatory mechanism that controls many different cellular processes. We and others have shown that sumoylation plays an indispensable role during mouse eye development. Whether sumoylation is implicated in ocular pathogenesis remains to be further studied.

Localization Patterns of Sumoylation Enzymes E1, E2 and E3 in Ocular Cell Lines Predict Their Functional Importance.

Purpose: It is well established now that protein sumoylation acts as an important regulatory mechanism mediating control of ocular development through regulation of multiple transcription factors. Yet the functional mechanisms of each factor modulated remain to be further explored using the available in vitro systems. In this regard, various ocular cell lines including HLE, FHL124, αTN4-1, N/N1003A and ARPE-19 have been demonstrated to be useful for biochemical and molecular analyses of normal physiology and pathogenesis.

Analysis of the Differential Expression Patterns of Sumoylation Enzymes E1, E2 and E3 in Ocular Cell Lines.

Purpose: Protein sumoylation is a well established regulatory mechanism to control many cellular processes such as chromatin structure dynamics, transcriptional regulation of gene expression, cell proliferation and differentiation, cell transformation and carcinogenesis, autophagy and senescence. In the vertebrate vision system, we and others have revealed that sumoylation plays important roles in regulating differentiation of several ocular tissues during eye development. To further elucidate the functional mechanisms of sumoylation, in vitro assay systems are needed.

Localization Analysis of Seven De-sumoylation Enzymes (SENPs) in Ocular Cell Lines.

Purpose: It is now well established that protein sumoylation acts as an important regulatory mechanism modulating functions over three thousand proteins. In the vision system, protein conjugation with SUMO peptides can regulate differentiation of multiple ocular tissues. Such regulation is often explored through analysis of biochemical and physiological changes with various cell lines in vitro.

Differential Expression of Seven De-sumoylation Enzymes (SENPs) in Major Ocular Tissues of Mouse Eye.

Purpose: Protein Sumoylation is one of the most important and prevalent posttranscriptional modification. Increasing evidence have shown that the SENPs (sentrin/SUMOspecific proteases) are critical for steady-state levels of SUMO modification of target proteins, and protein de-sumoylation modulates a great diversity of biological processes including transcription, development, differentiation, neuroprotection, as well as pathogenesis. In the vertebrate eye, we and others have previously shown that sumoylation participated in the differentiation of major ocular tissues including retina and lens.

Sodium Iodate-Induced Mouse Model of Age-Related Macular Degeneration Displayed Altered Expression Patterns of Sumoylation Enzymes E1, E2 and E3.

Purpose: Protein sumoylation is a highly dynamic and reversible post-translational modification, involving covalently conjugation of the small ubiquitin-like modifier (SUMO) to the lysine residue of the target protein. Similar to ubiquitination, sumoylation is catalyzed by E1, E2 and several E3 ligases. However, sumoylation usually does not cause protein degradation but alter the target function through diverse mechanisms.

The Sumoylation Modulated Tumor Suppressor p53 Regulates Cell Cycle Checking Genes to Mediate Lens Differentiation.

Purpose: The tumor suppressor p53 is a master regulator of apoptosis and also plays a key role in cell cycle checking. In our previous studies, we demonstrated that p53 directly regulates Bak in mouse JB6 cells and that p53-Bak signaling axis plays an important role in mediating EGCG-induced apoptosis. Furthermore, we have recently demonstrated that the same p53-Bak apoptotic signaling axis executes an essential role in regulating lens cell differentiation.

Analysis of Non-Sumoylated and Sumoylated Isoforms of Pax-6, the Master Regulator for Eye and Brain Development in Ocular Cell Lines.

Purpose: Pax-6 is a master regulator for eye and brain development. Previous studies including ours have shown that Pax-6 exists in 4 major isoforms. According to their sizes, they are named p48, p46, p43 and p32 with the corresponding molecular weight of 48, 46, 43 and 32 kd, respectively.

Altered Expression Patterns of the Sumoylation Enzymes E1, E2 and E3 Are Associated with Glucose Oxidase- and UVA-Induced Cataractogenesis.

Purpose: Protein sumoylation is a well established regulatory mechanism that regulates chromatin structure and dynamics, cell proliferation and differentiation, stress response and cell apoptosis. In the vertebrate eye, we and others have shown that sumoylation plays an indispensable role in regulating eye development. During stress induction and aging process, the ocular tissues gradually loss their normality and develop major ocular diseases such as cataract and aging-related macular degeneration.

Determination of Expression Patterns of Seven De-sumoylation Enzymes in Major Ocular Cell Lines.

Purpose: Accumulated evidence have well established that protein sumoylation plays multiple roles in various cellular processes. In the vertebrate eye, we and others have demonstrated that sumoylation displays indispensable roles in regulating eye development. Various ocular cell lines including human embryonic cell line (FHL124), the SV40-large T-transformed human lens epithelial cell line (HLE), the SV40-large T-transformed mouse lens epithelial cell line (αTN4-1), the rabbit lens epithelial cell line (N/N1003A) and the human retina pigment epithelial cell line (ARPE-19) have been extensively used for studying various cellular functions and disease processes including sumoylation functions, and mechanisms for cataract and age-related macular degeneration (AMD).

Differential Expression of Sumoylation Enzymes SAE1, U BA2, UBC9, PIAS1 and RanBP2 in Major Ocular Tissues of Mouse Eye.

Background: It is now well established that protein sumoylation is an important mechanism to regulate multiple cellular processes including gene transcription, chromatin structure, cell proliferation and differentiation, as well as pathogenesis.

Objective: In the vertebrate eye, we and others have previously shown that sumoylation can regulate differentiation of major ocular tissues including retina and lens. However, the expression patterns of the three types of sumoylation enzymes, the activating enzymes SAE1 and UBA2, the conjugating enzyme UBC9, and the ligating enzymes such as RanBP2 and PIAS1 have not been well studied in the ocular tissues.

The small heat shock protein αA-crystallin negatively regulates pancreatic tumorigenesis.

Our recent study has shown that αA-crystallin appears to act as a tumor suppressor in pancreas. Here, we analyzed expression patterns of αA-crystallin in the pancreatic tumor tissue and the neighbor normal tissue from 74 pancreatic cancer patients and also pancreatic cancer cell lines. Immunocytochemistry revealed that αA-crystallin was highly expressed in the normal tissue from 56 patients, but barely detectable in the pancreatic tumor tissue.

[Comparison on discriminatory power of different variable number tandem repeats locus-set on genotyping of mycobacterium tuberculosis isolated in China].

Objective: To evaluate the application of different variable number tandem repeats (VNTR) locus in genotyping of Mycobacterium tuberculosis (M.tuberculosis) strains isolated from eight provinces in China, and to find the suitable locus-set of VNTR for epidemical strains in China.

Methods: All 140 M.

[The influence of lysogenic phage on biofilm formation of Pseudomonas aeruginosa].

Objective: To investigate the effect of the lysogenic phage Ppa3094 on the biofilm formation of PA3094.

Methods: The modified plate culture method was used to established the biofilm model in vitro. The viable counts of bacteria in biofilm were detected by MTT method; The real-time RT-PCR was applied to measure the expression level of algC and algD during the biofilm formtion of PA3094 and PA3094-L.

[Quantification of class 1 integrase gene expression of Pseudomonas aeruginosa in biofilm].

Objective: To study the molecular mechanism of integron related gene transfer in biofilm and aqueous culture of P. aeruginosa by investigating the expression level of intI1 mRNA in class 1 integron positive strains.

Methods: A competitive reverse transcription-PCR (cRT-PCR) method was designed to quantify class 1 integrase mRNA production in two clinical P.

[Analysis of class I integrons in metalloenzyme-producing Pseudomonas aeruginosa].

Objective: To investigate class I integrons and integrated gene cassettes in metalloenzyme-producing Pseudomonas aeruginosa.

Methods: A total of 68 isolated clinical strains of Pseudomonas aeruginosa were subjected to PCR analysis with primers specific for bla(IMP-1) and bla(VIM). The positive strains then underwent examination for class I integrons and integrated gene cassettes with PCR with primers specific to class I integrase ((IntI)1) and integrated gene cassettes, followed by sequence analysis for some of the positive strains.

[Establishing a real-time PCR assay for anatid herpesvirus 1].

Objectives: To develop a real-time quantitative PCR assay to detect duck plague virus (DPV) for the rapid diagnosis of DPV infection, the investigation of its nosogenesis and the screening of effective antiviral drugs.

Methods: The primer and probe were designed according to the gene sequence of DPV DNA polymerase gene. To establish a standard curve, a plasmid containing 125 bp PCR product was constructed and severed as a positive control.

[Quantification for biofilm formation of pseudomonas aeruginosa isolates and their genotypic analysis].

Objective: To probe the correlation between the ability of biofilm formation of Pseudomonas aeruginosa isolates and their genotypes.

Methods: Forty-eight Pseudomonas aeruginosa isolates were tested for their biofilm formation with a modified microtiter test and were analyzed by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). The percent similarity between their genetic fingerprints and cluster analysis was performed and worked out using computer software.

[The cloning and expression of rhlR, a quorum sensing gene in Pseudomonas aeruginosa PAO1, and a study of its effect on bacterial clearance rate in mouse lung].

Objective: To inquire about the molecular characteristics of rhlR, a Quorum Sensing gene in Pseudomonas aeruginosa (P. aeruginosa) PAO1, and to explore the immunogenicity of RhlR protein in mouse.

Methods: The rhlR gene of PAO1 was amplified by PCR and cloned into pGEX4T-1 plasmid.