Mixed linked leukemia 4 (MLL4) is a specific methyltransferase of histone 3 position lysine 4 (H3K4). It is also one of the important members of COMPASS/Set1-like protein complex. Both MLL4 protein itself and its mediated H3K4 methylation modification can cause changes in chromatin structure and function, thus regulating gene transcription and expression. With the studies of MLL4 protein in recent years, the roles of MLL4 gene, MLL4 protein and protein complex in the development of tissues and organs, tumor diseases and other physiological and pathophysiological processes have been gradually revealed. In this paper, the research progress of MLL4 gene, MLL4 protein characteristics, biological function and its effect on disease were reviewed, in order to further understand the effect of histone methyltransferase on gene expression regulation, as well as its non-enzyme dependent function. This paper may provide new ideas for the prevention, diagnosis and treatment of related diseases.
DNA-Binding Proteins ; physiology ; Histone-Lysine N-Methyltransferase ; physiology ; Histones ; chemistry ; Humans ; Methylation

By using an RAD peptide display system derived from the ATPase domain of recombinase RadA of Pyrococcus furiosus, an anti-hCG antibody-like molecule was prepared by grafting an hCG-binding peptide to the RAD scaffold. After linking to sfGFP gene, a gene of hCG peptide-grafted RAD was synthesized and cloned into a bacterial expression vector (pET30a-RAD/hCGBP-sfGFP). The vector was transformed into Escherichia coli, and expression of the fusion protein was induced. After isolation and purification of the fusion protein, its binding affinity and specificity to hCG were determined by using a process of immunoabsorption followed by GFP fluorescence measurement. A comparison of hCG-binding activity with a similarly grafted single-domain antibody based on a universal scaffold was performed. The measurement of hCG-binding affinity and specificity revealed that the grafted RAD has an optimally high binding affinity and specificity to hCG, which are better than the grafted single-domain antibody. Moreover, the affinity and specificity of grafted RAD molecule are comparable to those of a commercial monoclonal antibody. In addition, the hCG-binding peptide-grafted RAD molecule has a relatively high biochemical stability, making it a good substitute for antibody with potential application.
Antibodies, Monoclonal ; chemistry ; isolation & purification ; metabolism ; Antibody Specificity ; DNA-Binding Proteins ; genetics ; metabolism ; Escherichia coli ; genetics ; Escherichia coli Proteins ; metabolism ; Humans ; Peptides ; Recombinant Fusion Proteins ; genetics ; metabolism

As a dioxygenase, Ten-Eleven Translocation 2 (TET2) catalyzes subsequent steps of 5-methylcytosine (5mC) oxidation. TET2 plays a critical role in the self-renewal, proliferation, and differentiation of hematopoietic stem cells, but its impact on mature hematopoietic cells is not well-characterized. Here we show that Tet2 plays an essential role in osteoclastogenesis. Deletion of Tet2 impairs the differentiation of osteoclast precursor cells (macrophages) and their maturation into bone-resorbing osteoclasts in vitro. Furthermore, Tet2 mice exhibit mild osteopetrosis, accompanied by decreased number of osteoclasts in vivo. Tet2 loss in macrophages results in the altered expression of a set of genes implicated in osteoclast differentiation, such as Cebpa, Mafb, and Nfkbiz. Tet2 deletion also leads to a genome-wide alteration in the level of 5-hydroxymethylcytosine (5hmC) and altered expression of a specific subset of macrophage genes associated with osteoclast differentiation. Furthermore, Tet2 interacts with Runx1 and negatively modulates its transcriptional activity. Our studies demonstrate a novel molecular mechanism controlling osteoclast differentiation and function by Tet2, that is, through interactions with Runx1 and the maintenance of genomic 5hmC. Targeting Tet2 and its pathway could be a potential therapeutic strategy for the prevention and treatment of abnormal bone mass caused by the deregulation of osteoclast activities.
5-Methylcytosine ; analogs & derivatives ; chemistry ; metabolism ; Animals ; Cell Differentiation ; Cells, Cultured ; Core Binding Factor Alpha 2 Subunit ; genetics ; metabolism ; DNA-Binding Proteins ; physiology ; Genome ; Genomics ; Mice ; Mice, Knockout ; Osteoclasts ; cytology ; metabolism ; Proto-Oncogene Proteins ; physiology

BACKGROUNDFour single nucleotide polymorphisms (SNPs) in the modulator recognition factor 2/AT-rich interaction domain 5B (MRF2/ARID5B) gene located at chromosome 10q21.2 have been shown to be associated with both type 2 diabetes mellitus (T2DM) and coronary artery disease in a Japanese cohort. This study aimed to investigate the relationship between these SNPs (rs2893880, rs10740055, rs7087507, rs10761600) and new-onset T2DM and lipid metabolism in a Northern Chinese population.

METHODSThis was a case-control study. The rs2893880, rs10740055, rs7087507, and rs10761600 genetic variants were genotyped by SNPscan and analyzed in relation to T2DM susceptibility in 2000 individuals (999 with newly diagnosed T2DM and 1001 controls without diabetes mellitus). Associations between the MRF2/ARID5B genetic models and T2DM were determined by multivariate logistic regression.

RESULTSRegarding the rs10740055 SNP, AA was associated with a higher risk of T2DM compared with codominant-type CC (adjusted by sex, age, and body mass index [BMI], P= 0.041, odds ratio [OR] = 1.421, 95% confidence interval [CI] 1.014-1.991). Meanwhile, AA individuals were at increased risk of presenting with T2DM compared with individuals with CC or a single C (adjusted by sex, age, and BMI, P= 0.034, OR = 1.366, 95% CI 1.023-1.824). With respect to rs10761600, AT contributed to a higher risk of T2DM compared with AA (adjusted by sex, age, and BMI, P= 0.013, OR = 1.585, 95% CI 1.101-2.282), while TT also increased the risk of presenting with T2DM compared with AA or A (adjusted by sex, age, and BMI, P= 0.004, OR = 1.632, 95% CI 1.166-2.284). High-density lipoprotein cholesterol (HDL-C) levels were significantly different among the three genotypes of rs7087507 in the controls (P = 0.048) (GG>GA).

CONCLUSIONSThe present results identified MRF2/ARID5B as a potential susceptibility gene for new-onset T2DM in a Northern Chinese population, while the rs7087507 SNP was associated with HDL-C levels. Further larger studies are required to validate these findings.

Asian Continental Ancestry Group ; Case-Control Studies ; DNA-Binding Proteins ; chemistry ; genetics ; metabolism ; Diabetes Mellitus, Type 2 ; genetics ; metabolism ; Genetic Association Studies ; Genetic Predisposition to Disease ; genetics ; Genotype ; Humans ; Lipid Metabolism ; genetics ; physiology ; Odds Ratio ; Polymorphism, Single Nucleotide ; genetics ; Transcription Factors ; chemistry ; genetics ; metabolism

As an important telomere binding protein, TPP1 protects the ends of telomeres and maintains the stability and integrity of its structure and function by interacting with other five essential core proteins (POT1, TRF1, TRF2, TIN2, and RAP1) to form a complex called Shelterin. Recently, researchers have discovered that TPP1 participates in protection of telomeres and regulation of telomerase activity. The relationship between TPP1 and tumorigenesis, tumor progression and treatment has also been investigated. This paper reviews the latest findings of TPP1 regarding to its structure, function and interaction with other proteins involved in tumorigenesis.
Chromosomal Instability ; DNA Damage ; Humans ; Neoplasms ; genetics ; Telomere ; Telomere-Binding Proteins ; chemistry ; physiology

BACKGROUND: The incidence and etiology of hepatocellular carcinoma (HCC) vary widely according to race and geographic regions. The insertional mutagenesis of adeno-associated virus 2 (AAV2) has recently been considered a new viral etiology of HCC. The aim of this study was to investigate the frequency and clinical characteristics of AAV2 in Korean patients with HCC. METHODS: A total of 289 unrelated Korean patients with HCC, including 159 Hepatitis-B-related cases, 16 Hepatitis-C-related cases, and 114 viral serology-negative cases, who underwent surgery at the Samsung Medical Center in Korea from 2009 to 2014 were enrolled in this study. The presence of AAV2 in fresh-frozen tumor tissues was investigated by DNA PCR and Sanger sequencing. The clinical and pathological characteristics of AAV2-associated HCC in these patients were compared with previous findings in French patients. RESULTS: The AAV2 detection rate in Korean patients (2/289) was very low compared with that in French patients (11/193). Similar to the French patients, the Korean patients with AAV2-related HCC showed no signs of liver cirrhosis. The Korean patients were younger than the French patients with the same AAV2-associated HCC; the ages at diagnosis of the two Korean patients were 47 and 39 yr, while the median age of the 11 French patients was 55 yr (range 43-90 yr). CONCLUSIONS: AAV2-associated HCC was very rare in Korean patients with HCC. Despite a limited number of cases, this study is the first to report the clinical characteristics of Korean patients with AAV2-associated HCC. These findings suggest epidemiologic differences in viral hepatocarcinogenesis between Korean and European patients.
Adult ; Asian Continental Ancestry Group ; Capsid Proteins/genetics ; Carcinoma, Hepatocellular/etiology/*pathology/virology ; DNA, Viral/chemistry/genetics/metabolism ; DNA-Binding Proteins/genetics ; Dependovirus/*genetics/isolation & purification/pathogenicity ; Female ; Humans ; Incidence ; Inverted Repeat Sequences/genetics ; Liver Neoplasms/etiology/*pathology/virology ; Male ; Middle Aged ; Parvoviridae Infections/complications/epidemiology ; Polymerase Chain Reaction ; Republic of Korea ; Sequence Analysis, DNA ; Viral Proteins/genetics

CHARGE syndrome MIM #214800 is an autosomal dominant syndrome involving multiple congenital malformations. Clinical symptoms include coloboma, heart defects, choanal atresia, retardation of growth or development, genital hypoplasia, and ear anomalies or deafness. Mutations in the chromodomain helicase DNA binding protein 7 (CHD7) gene have been found in 65-70% of CHARGE syndrome patients. Here, we describe a 16-month-old boy with typical CHARGE syndrome, who was referred for CHD7 gene analysis. Sequence analysis and multiplex ligation-dependent probe amplification were performed. A heterozygous 38,304-bp deletion encompassing exon 3 with a 4-bp insertion was identified. There were no Alu sequences adjacent to the breakpoints, and no sequence microhomology was observed at the junction. Therefore, this large deletion may have been mediated by non-homologous end joining. The mechanism of the deletion in the current case differs from the previously suggested mechanisms underlying large deletions or complex genomic rearrangements in the CHD7 gene, and this is the first report of CHD7 deletion by this mechanism worldwide.
Alu Elements/genetics ; Base Sequence ; CHARGE Syndrome/diagnosis/*genetics ; DNA/chemistry/metabolism ; *DNA End-Joining Repair ; DNA Helicases/*genetics/metabolism ; DNA-Binding Proteins/*genetics/metabolism ; Exons ; Gene Dosage ; Heterozygote ; Humans ; Infant ; Male ; Multiplex Polymerase Chain Reaction ; Mutation ; Sequence Analysis, DNA ; *Sequence Deletion

SWI1 is a member of a new class of tumor DNA-binding proteins named as the AT-rich interaction domain family (ARID), and considered to bind with AT base pairs specifically. Genomic and functional data support ARID1A as a tumor suppressor because ARID1A/BAF250a (SWI1) subunit of the SWI/SNF chromatin-remodeling complex has emerged as recurrently mutated in a broad array of tumor types. But the crystal structure of SWI1 has not been solved as yet. Using docking and molecular dynamics, we predicted the DNA interaction pattern of human SWI1 ARID and made comparisons with the other two representative ARID family members, human Mrf-2 ARID and Drosophila Dri ARID. Dynamic results revealed that the N-terminal and loop L1 of SWI1 ARID bound with the DNA major groove, while the loop L2 and helix H6 bound with the minor groove. Moreover, it was found that SWI1 ARID bound with DNA apparently in a sequence-nonspecific manner. It was concluded that SWI1 ARID can form stable complex with sequence-nonspecific DNA segment comparing to Mrf-2 ARID/DNA and Dri ARID/DNA sequence-specific complexes.
Binding Sites ; DNA ; chemistry ; metabolism ; DNA-Binding Proteins ; chemistry ; metabolism ; Drosophila Proteins ; chemistry ; Homeodomain Proteins ; chemistry ; Humans ; Models, Molecular ; Molecular Docking Simulation ; Molecular Dynamics Simulation ; Nuclear Proteins ; chemistry ; Protein Structure, Tertiary ; Transcription Factors ; chemistry ; metabolism

Ongoing study on the chemical constituents of the roots of Macleaya microcarpa led to the isolation of eight compounds of derivatives of triterpenes and organic acids in addition to some previously identified benzophenanthridines. The eight compounds were identified by spectroscopic methods as well as comparison with literature values as 1-oxo-2, 22 (30)-hopandien-29-oic acid (1), 3-oxo-12-oleanen-30-oic acid (2), 3α-hydroxy-12-oleanen-30-oic acid (3), 3β-hydroxy-12-oleanen-30-oic acid (4), ferulic acid (5), ferulic acid 4-O-β-D-glucoside (6), 3-O-feruloylquinic acid (7), and methyl 3-O-feruloylquinate (8). Of which, 1 is a new triterpenoid of hopanes and 2-8 are isolated from M microcarpa for the first time. In order to discover natural active compounds as potential agents of anti-ulcerative colitis (UC), an in vitro drug high-throughput screening model targeted x-box-binding protein 1 (xbp1) was employed to evaluate the activity of the major chemical constituents of M microcarpa. The result confirmed that two dihydrobenzophenanthridines, dihydrosanguinarine (9) and dihydrochelerythrine (10), showed a certain activity on activating the transcription of xbpl, a transcription factor (TF) associated with the occurrence, development, and potential treatment of UC, with their relative activating ratios being 1.76 and 1.77 times, respectively, as compared with control group.
Anti-Ulcer Agents ; chemistry ; Benzophenanthridines ; chemistry ; DNA-Binding Proteins ; genetics ; Isoquinolines ; chemistry ; Papaveraceae ; chemistry ; Plant Roots ; chemistry ; Regulatory Factor X Transcription Factors ; Transcription Factors ; genetics ; Transcription, Genetic ; Triterpenes ; chemistry

This study was aimed to identify the mutation of the whole coding region of shock transcription factor 4 (HSF4) gene in a Chinese family with autosomal dominant congenital cataract (ADCC). All exons of HSF4 were amplified by PCR. Sequence analysis of PCR products was performed. Restriction fragment length polymorphism (RFLP) analysis was conducted to confirm the pathogenic mutation. The results showed that a C to T substitution occurred at nucleotide 331 in patients of this family, leading to the replacement of the amino acid arginine-111 with cysteine in exon 3. RFLP analysis showed that the amino acid change was co-segregated with all affected individuals. It was concluded that the new mutation of c.331C>T in HSF4 DNA may be responsible for the autosomal dominant congenital cataract in this family.
Amino Acid Sequence ; Animals ; Base Sequence ; Cataract ; congenital ; genetics ; China ; DNA Primers ; DNA-Binding Proteins ; chemistry ; genetics ; Female ; Genes, Dominant ; Heat Shock Transcription Factors ; Humans ; Male ; Molecular Sequence Data ; Mutation ; Pedigree ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Sequence Homology, Amino Acid ; Transcription Factors ; chemistry ; genetics