Objective To analyze the effect of GC-rich DNA fragments on the level of transgenic expression in Chinese hamster ovary (CHO) celts and its position effect.Methods The synthetic DNA fragment with GC-rich was cloned into the 5'or 3'or both 5'and 3'ends of expression cassette of expression vector.Three new expression vectors (pIRES-G1,pIRES-G2 and pIRES-G3) which was inserted with the GC-rich DNA fragments in different position were transfected CHO ceils,respectively,and then was observed under fluorescence microscope;the control vector was pIRES-EGFP.Stable transfected cell lines were screened under G418,and enhanced green fluorescent protein(EGFP) expression was analyzed by flow cytometry and the transgenic copy number was detected by quantitative real-time quantitative polymerase chain reaction (qRT-PCR).Results Three expression vectors with a GC-rich DNA fragments in different position were constructed successfully.The insertion of GC-rich DNA fragments at 3'end and both 5',3'ends of the box of expression vector could obviously improve the expression level of vector in CHO cells;and the expression level of the stably transfected CHO cells increased 1.39 fold and 1.32 fold compared to the control vector,respectively;the transgene copy number increased 1.32 fold and 1.24 fold compared with the control vector.While the insertion of GC-rich DNA fragments at 5'end of expression cassette had no obvious effect on the level of gene expression.Conclusion The role of DNA fragment with GC-rich in improving the transgenic expression of CHO cells is related to its position in the vector.The insertion of GC-rich DNA fragments at 3'end and both 5',3'ends of the box of expression vector can improve transgenic expression.

The effects of over-expression of ANXA10 gene on proliferation and apoptosis of hepato-cellular carcinoma cell line HepG2 were elucidated. The human ANXA10 gene was subcloned into the lentiviral vector, PGC-FU, to generate the lentiviral expression vector, PGC-FU-ANXA10. The corrected ANXA10 was confirmed by endoenzyme digestion, and sequencing. Recombinant lentiviruses were produced by 293T cells following the co-transfection of PGC-FU-ANXA10 with the packaging plasmids pHelper1.0 and pHelper2.0. The resulting recombinant lentiviruses carrying ANXA10 were then used to infect human embryonic kidney epithelial cells, and lentiviral particles were produced. The ANXA10 expression in 293T cells was detected by using fluorescent microscope and Western blotting. HepG2 cells were infected, and divided into PGC-Fu-ANXA10 group, PGC-Fu group and HepG2 cell group. The changes of ANXA10 mRNA and protein expression were detected by using RT-PCR and Western blotting respectively. Flow cytometry and MTT assay were performed to examine the changes in cell apoptosis and proliferation respectively. The recombinant PGC-FU-ANXA10 vector was successfully constructed, the ANXA10 protein was detected by using Western blotting, and virus titer was 2×10(8) TU/mL. The recombinant lentiviruses were effectively infected into HepG2 cells in vitro and the infection efficiency was 70%. At 72 h after infection, the ANXA10 mRNA and protein expression levels in PGC-Fu-ANXA10 group were significantly higher than in PGC-Fu group and HepG2 cell group (P<0.05); the in vitro growth inhibition rate of HepG2 cells in PGC-Fu-ANXA10 group was 24.65%, significantly higher than that in PGC-Fu group and HepG2 cell group (P<0.05), but there was no significant difference between PGC-Fu group and HepG2 cell group; the apoptosis rate in PGC-Fu-ANXA10 group, PGC-Fu group and HepG2 cell group was (51.92±1.41)%, (19.00±1.12)% and (3.59±0.89)% respectively. The apoptosis rate in PGC-Fu-ANXA10 group was significantly higher than in PGC-Fu group and HepG2 cell group (P<0.05). The recombinant lentiviruses PGC-FU-ANXA10 were constructed successfully and infected into HepG2 cells. The overexpression of ANXA10 gene can significantly inhibit proliferation and promote apoptosis of HepG2 cells in vitro.

The effects of over-expression of ANXA10 gene on proliferation and apoptosis of hepato-cellular carcinoma cell line HepG2 were elucidated. The human ANXA10 gene was subcloned into the lentiviral vector, PGC-FU, to generate the lentiviral expression vector, PGC-FU-ANXA10. The corrected ANXA10 was confirmed by endoenzyme digestion, and sequencing. Recombinant lentiviruses were produced by 293T cells following the co-transfection of PGC-FU-ANXA10 with the packaging plasmids pHelper1.0 and pHelper2.0. The resulting recombinant lentiviruses carrying ANXA10 were then used to infect human embryonic kidney epithelial cells, and lentiviral particles were produced. The ANXA10 expression in 293T cells was detected by using fluorescent microscope and Western blotting. HepG2 cells were infected, and divided into PGC-Fu-ANXA10 group, PGC-Fu group and HepG2 cell group. The changes of ANXA10 mRNA and protein expression were detected by using RT-PCR and Western blotting respectively. Flow cytometry and MTT assay were performed to examine the changes in cell apoptosis and proliferation respectively. The recombinant PGC-FU-ANXA10 vector was successfully constructed, the ANXA10 protein was detected by using Western blotting, and virus titer was 2×10(8) TU/mL. The recombinant lentiviruses were effectively infected into HepG2 cells in vitro and the infection efficiency was 70%. At 72 h after infection, the ANXA10 mRNA and protein expression levels in PGC-Fu-ANXA10 group were significantly higher than in PGC-Fu group and HepG2 cell group (P<0.05); the in vitro growth inhibition rate of HepG2 cells in PGC-Fu-ANXA10 group was 24.65%, significantly higher than that in PGC-Fu group and HepG2 cell group (P<0.05), but there was no significant difference between PGC-Fu group and HepG2 cell group; the apoptosis rate in PGC-Fu-ANXA10 group, PGC-Fu group and HepG2 cell group was (51.92±1.41)%, (19.00±1.12)% and (3.59±0.89)% respectively. The apoptosis rate in PGC-Fu-ANXA10 group was significantly higher than in PGC-Fu group and HepG2 cell group (P<0.05). The recombinant lentiviruses PGC-FU-ANXA10 were constructed successfully and infected into HepG2 cells. The overexpression of ANXA10 gene can significantly inhibit proliferation and promote apoptosis of HepG2 cells in vitro.
Annexins ; genetics ; Apoptosis ; genetics ; Carcinoma, Hepatocellular ; genetics ; Cell Line, Tumor ; Cell Proliferation ; Hep G2 Cells ; Humans ; Liver Neoplasms ; genetics

OBJECTIVE: To explore the genetic etiology of a child with Pitt-Hopkins syndrome. METHODS: A child who had presented at the Medical Genetics Center of Gansu Provincial Maternal and Child Health Care Hospital on February 24, 2021 and his parents were selected as the study subjects. Clinical data of the child was collected. Genomic DNA was extracted from peripheral blood samples of the child and his parents and subjected to trio-whole exome sequencing (trio-WES). Candidate variant was verified by Sanger sequencing. Karyotype analysis was also carried out for the child, and her mother was subjected to ultra-deep sequencing and prenatal diagnosis upon her subsequent pregnancy. RESULTS: The clinical manifestations of the proband included facial dysmorphism, Simian crease, and mental retardation. Genetic testing revealed that he has carried a heterozygous c.1762C>T (p.Arg588Cys) variant of the TCF4 gene, for which both parents had a wild-type. The variant was unreported previously and was rated as likely pathogenic based on the guidelines of the American College of Medical Genetics and Genomics (ACMG). Ultra-deep sequencing indicated that the variant has a proportion of 2.63% in the mother, suggesting the presence of low percentage mosaicism. Prenatal diagnosis of amniotic fluid sample suggested that the fetus did not carry the same variant. CONCLUSION The heterozygous c.1762C>T variant of the TCF4 gene probably underlay the disease in this child and has derived from the low percentage mosaicism in his mother.
Child ; Female ; Humans ; Male ; Pregnancy ; Intellectual Disability/genetics* ; Mosaicism ; Mothers ; Mutation ; Parents ; Transcription Factor 4/genetics*