Identification of immediate early gene X-1 as a cellular target gene of hcmv-mir-UL148D.

Human cytomegalovirus (HCMV) is a herpesvirus that causes congenital diseases and opportunistic infections in immunocompromised individuals. Its functional proteins and microRNAs (miRNAs) facilitate efficient viral propagation by altering host cell behavior. The identification of functional target genes of miRNAs is an important step in the study of HCMV pathogenesis. HCMV encodes at least 14 miRNAs, including hcmv-mir-UL148D, which resides in the HCMV UL/b' region. hcmv-mir-UL148D is the only miRNA encoded by the HCMV UL/b' region; however, its targets and functional effects have not yet been eludidated. In this study, hybrid-PCR screening was used to identify target genes and dual luciferase reporter assay was used to evaluate the binding effect of hcmv-miR-UL148D to the 3' untranslated region (3'UTR) of IEX-1. In addition, western blot analysis was used to detect the expression kinetics of IEX-1 protein and apoptosis assay was used to identify the effects of hcmv-miR-UL148D on cell apoptosis. The hybrid-PCR results showed that only one binding site in the 3'UTR of the cellular gene, human immediate early gene X-1 (IEX-1), was completely complementary to an 11 nucleotide (nt) sequence in the 5' terminus of hcmv-mir-UL148D, including the entire seed region. The binding site was demonstrated to be functional by dual luciferase reporter assay with a 47% repression of the relative luciferase activity. In an in vitro system of human embryonic kidney 293 (HEK293) cells, the ectopically expressed hcmv-mir-UL148D exhibited a downregulatory effect on IEX-1 expression, and decreased the cell apoptosis induced by transfected IEX-1. Our data demonstrate that hcmv-mir-UL148D targets the cellular gene, IEX-1, downregulating its expression and thus results in anti-apoptotic effects.

Sequence analysis of human cytomegalovirus US28 gene in low-passage clinical isolates from children and AIDS patients.

Human cytomegalovirus (HCMV) is often a dangerous opportunistic pathogen that causes significant morbidity and mortality in newborn children and immunocompromised patients. The different symptoms and tissue tropisms of HCMV infection may result from genetic polymorphism. This study investigated the sequence variability of the HCMV US28 ORF, which shows sequence homology to the G protein-coupled receptor. HCMV isolated from suspected pediatric cases and isolates from AIDS patients were compared in order to examine the possible associations between polymorphisms and pathogenesis. Seventy children with suspected congenital HCMV infection, who suffered from jaundice (47), megacolon (10), and microcephaly (13), and 17 AIDS patients, were studied. Mutation was prevalent among the sequences of US28, with a focus on the two ends of US28. The important functional groups of US28 are highly conserved. An unrooted tree showed that all sequences from suspected congenitally infected infants and AIDS patients were divided into three groups. Comparison showed that most of the sequences (12/17) from pediatric patients were included in the first group (G1), whereas most of the sequences (11/17) from AIDS patients were included in the third group (G3). The specific high mutation sites in US28 from children were located at the C terminus of the protein, whereas those from AIDS patients were located at the N terminus. We demonstrated the existence of polymorphisms among the US28 genes of clinical isolates of HCMV from infants with suspected congenital infection. Comparison of US28 sequences from AIDS patients with those from children showed that both sequences have their own specific high mutation points.

[Transcription pattern of UL131A-128 mRNA in HCMV clinical strains].

OBJECTIVE: To study and research the transcription pattern of UL131A-128 mRNA in human cytomegalovirus (HCMV) clinical low passage strains. METHODS: The UL131A-128 mRNAs of from different clinical strains and kinetic periods were amplified using 3' RACE and analyzed by sequencing. Meanwhile, clones containing UL131A-128 transcripts in a HCMV cDNA library of clinical strain were selected and sequenced. RESULTS: It is successful to obtain the transcription pattern of UL131A, UL130 and UL128 gene in HCMV clinical low passage strains, the UL131A gene consisted of two exons and the coding region of UL130 gene was not interrupted by any intron in the region as reported before. However, the transcript of UL128 gene showed two patterns, one pattern consisted of the three exons, the length is 519bp, and the other one contained the three exons and the sequence of the first intron further, the length is 642bp. The quantities of UL128 transcript containing the sequence of the first intron were higher than that of transcript only containing the three exons in the studied clinical strains at all kinetic classes. It was demonstrated that the UL131A-128 mRNA were expressed with immediately early, early and late kinetics. The result of 3'RACE and HCMV cDNA library of clinical strain is conformity. CONCLUSIONS: Our results demonstrated that the UL131A, UL130 and UL128 genes were transcribed with 3'-coterminal, although the initiation points of their mRNA may be different. The variation of the transcripts found in our study indicated complex nature of transcription of UL131A-128 genes in HCMV clinical strains.

Characteristics of HPV prevalence among women in Liaoning province, China.

OBJECTIVES: To investigate the prevalence rates of specific human papillomavirus (HPV) types infecting women in Liaoning Province, China. METHODS: Specimens from 4780 patients with cervical disease and 165 age-matched controls were tested for HPV genotypes using a chip hybridization assay. RESULTS: The infection rates were 35.66% for patients with cervicitis, 54.61% for those with ASCUS, 64.14% for those with CIN, 83.76% for those with cervical cancer in situ, and 83.12% for those with invasive cervical cancer. The most common HPV genotype was HPV-16, followed by HPV-58, HPV-52, HPV-33, HPV-53, and HPV-31. There were 1529 single and 731 multiple infections among the 4780 patients. Single infections with high-risk genotypes were associated with various cervical diseases. HPV-16 was present in 399 of the patients with multiple infections. CONCLUSION: Compared with prevalence rates for other populations, the rates of specific HPV types infecting women are different in Liaoning Province of China.

Human cytomegalovirus UL138 open reading frame is highly conserved in clinical strains.

OBJECTIVE: To investigate the variability of human cytomegalovirus (HCMV) UL138 open reading frame (ORF) in clinical strains. METHODS: HCMV UL138 ORF was amplified by polymerase chain reaction (PCR) and PCR amplification products were sequenced directly, and the data were analyzed in 19 clinical strains. RESULTS: UL138 ORF in all 30 clinical strains was amplified successfully. Compared with that of Toledo strain, the nucleotide and amino acid sequence identities of UL138 ORF in all strains were 97.41% to 99.41% and 98.24% to 99.42%, respectively. All of the nucleotide mutations were substitutions. The spatial structure and post-translational modification sites of UL138 encoded proteins were conserved. The result of phylogenetic tree showed that HCMV UL138 sequence variations were not definitely related with different clinical symptoms. CONCLUSION: HCMV UL138 ORF in clinical strains is high conservation, which might be helpful for UL138 encoded protein to play a role in latent infection of HCMV.

[The investigation of the relationship between the phenotypes of 46, XX males and the SRY gene].

OBJECTIVE: To investigate the relationship between the phenotypes in XX male patients and the sex determining region(SRY) gene. METHODS: Multiple polymerase chain reactions were carried out in 6 male patients with karyotype of 46, XX, and then the PCR products were sequenced directly. RESULTS: Three cases of male infertility were positive for the SRY gene without evident malformation in their extra genitalia, while 3 cases with testes were negative for the SRY gene, with evident malformation in their extra genitalia. CONCLUSION: The SRY gene is key in sex determination and development, yet there might be other important genes involved.

[Polymorphism analysis of human cytomegalovirus UL150 gene in low passage clinical isolates].

OBJECTIVE: To investigate the polymorphism of human cytomegalovirus UL150 gene in low passage clinical isolates and try to study the relationship between the polymorphism and different pathogenesis of congenital HCMV infection. METHODS: PCR was performed to amplify the entire HCMV UL150 gene region of 29 clinical isolates, which had been proven containing detectable HCMV-DNA by using FQ-PCR. PCR amplification products were sequenced directly and the data were analysed. RESULTS: 25 among 29 isolates were amplified and 18 isolates were sequenced successfully. By comparison with the sequence of Toledo and Merlin, the length of UL150 ORFs in all 18 clinical isolates was similar to that of Merlin than Toledo. CONCLUSION: HCMV UL150 DNA and deduced amino acid sequences is hypervariability.

Sequence conservation of human cytomegalovirus UL140 open reading frame in clinical strains.

OBJECTIVE: To investigate the variability of human cytomegalovirus (HCMV) UL140 open reading frame (ORF) in clinical strains, and to explore the relationship between the variability of UL140 ORF and different symptoms of HC-MV infection. METHODS: HCMV UL140 ORF was amplified by polymerase chain reaction and sequenced selectedly in 30 clinical strains. RESULTS: UL140 ORF of all clinical strains was amplified successfully. Compared with that of Toledo strain, the nucleotide and amino acid sequence identities among all strains were 96.5%-100.0% and 95.2%-100.0%, respectively. All of the nucleotide changes were substitutions. The post-translational modification sites were conserved. The result of phylogenetic tree showed that the strains did not cluster according to different clinical symptoms. CONCLUSION: HCMV UL140 ORF in clinical strains is highly conserved, which may play an important role in HC-MV infection.

[Polymorphism of human cytomegalovirus UL134 gene in low-passage clinical isolates].

OBJECTIVE: Human cytomegalovirus (HCMV) displays genetic polymorphisms. Nineteen open reading frames (ORFs, UL133-UL151) found in the Toledo strain of HCMV and other low-passage clinical isolates may be essential for viral infection. This study aimed to analyze the polymorphism of HCMV UL134 gene in clinical isolates and explore the relationship between the polymorphism and HCMV infection. METHODS: PCR was performed to amplify entire UL134 region in 32 clinical isolates, which had been proven as HCMV-DNA positive by FQ-PCR. PCR products were sequenced. RESULTS: All of the 32 isolates were amplified and sequenced successfully. HCMV UL134 gene was highly conserved in the clinical isolates. UL134 ORF and its predicted protein in the clinical strains displayed 96.4%-98.3% nucleotide identity and 92.7%-94.9% amino acid identity respectively compared to those in the Toledo strain. A new posttranslational modification site, sulfationcamp (SUL) site, was found in UL134 protein of all of the clinical isolates except 35j. CONCLUSIONS: HCMV UL134 gene in clinical isolates was highly conserved. No substantial relation was found between UL134 gene and HCMV infectious diseases.

Genetic polymorphism of UL144 open reading frame of human cytomegalovirus DNA detected in colon samples from infants with Hirschsprung's disease.

AIM: To explore the genetic diversities of UL144 open reading frame (ORF) of cytomegalovirus DNA detected in colon tissue from infants with Hirschsprung's disease (HD) by sequencing UL144 DNA in 23 aganglionic colon tissue and 4 urine samples from 25 HD infants. METHODS: Nest PCR was performed for amplification of the UL144 gene. The UL144 gene was analyzed with softwares, such as DNAclub, BioEdit, PROSITE database, and DNAstar. RESULTS: The strains from HD patients were distributed among three genotypes of UL144: group 1A (64%), group 2 (24%), and group 3 (12%). The UL144 genotypes between strains from HD and control group were compared by chi square test (c2 = 1.870, P = 0.393). Strains from the colon were sporadically distributed in UL144 genotypes. CONCLUSION: There are genetic diversities of UL144 ORF in colon tissue of infants with HD. However, cytomegalovirus UL144 genotypes are not associated with clinical manifestations of HD.

MeCP2 gene mutation analysis in autistic boys with developmental regression.

Autism and Rett syndrome are both pervasive developmental disorders and share many characteristics in common. One of these features is developmental regression with loss of social, cognitive and language skills after a period of apparently normal development during the first 1-2 years of life, which raises the question of whether there is a common pathway underlying regression in these two disorders. The Rett syndrome gene was identified as MeCP2 gene on Xq28, a powerful transcriptional repressor. To explore its possible role in the etiology of autism and involvement in regression, we searched for MeCP2 gene mutations in a well characterized sample of 31 autistic boys with developmental regression by direct sequencing. One sequence variant in 3' untranslated region was observed. The patient inherited the variant from his unaffected mother, so it may be a rare polymorphism. No coding sequence variant was found in any of the patients tested. We conclude that mutations in the coding sequence of MeCP2 are not a frequent cause of regression in autism. The long 3' untranslated region of MeCP2 is highly conserved across species, suggesting that they are important for the post-transcriptional regulation of MeCP2 gene. It may be worthwhile extending the mutation screening, with a larger sample of strictly defined phenotype, to regulatory elements and untranslated regions of this gene, to explore to what degree MeCP2 gene is involved in the etiology of autism and its possible role in the regression of autism.

Genetic variability of human cytomegalovirus UL132 gene in strains from infected infants.

Human cytomegalovirus (HCMV) displays genetic polymorphisms. HCMV infects a number of organs and cell types, leading to the hypothesis that HCMV disease and tissue tropism may be related to specific sequence variability. A gene in UL/b' of HCMV, UL132 open reading frame (ORF), encodes glycoprotein (gpUL132) which is identified as a low-abundance structural component of HCMV. In this study, the sequence variability of the UL132 gene was studied in 30 clinical strains. The results showed that a large number of nucleotide non-synonymous substitutions occurred in the UL132 ORF, particularly in the 5' half, in comparison to the UL132 of reference strain, Toledo. The UL132 variants of the clinical strains were clustered clearly into three major groups in the phylogenetic tree: G1(10/30), G2(9/30), and G3(11/30). The precise definition of UL132 genotypes and their putative functions would be helpful in a better understanding of the HCMV.

Polymorphisms of human cytomegalovirus UL148A, UL148B, UL148C, UL148D genes in clinical strains.

BACKGROUND: Clinical isolates of human cytomegalovirus (HCMV) display polymorphisms in multiple genes. Some authors have suggested that polymorphisms are implicated in HCMV-induced immunopathogenesis, as well as in strain-specific behaviors, such as tissue-tropism and the ability to establish persistent or latent infections. OBJECTIVE: To describe the features of HCMV UL148A, UL148B, UL148C and UL148D open reading frames (ORFs) and the variable sites within the frames in clinical strains. STUDY DESIGN: PCR was performed to amplify these ORFs in 22 clinical strains. PCR amplification products were sequenced directly and analyzed. RESULTS: The nucleotide diversity of UL148A, UL148B, UL148C and UL148D ORFs in studied strains is 0.5-8.3%, 0.5-4.6%, 0.5-3% and 1.7-8.1%, respectively; the amino acid diversity of their putative proteins is 1.3-6.3%, 1.3-5.0%, 1.3-3.9% and 1.7-8.1%, respectively, related to the Merlin strain. The modification sites of UL148A, UL148B, UL148C and UL148D predicted proteins from strains in unpassaged urine samples were conserved, except for strain U96, compared with that of the Merlin strain. By phylogenetic and statistical analysis, the UL148A and UL148D sequences of clinical strains were classified into three groups. CONCLUSION: Compared to the UL148A, UL148B and UL148D ORFs, the UL148C ORF was relatively conserved, as was the amino acid sequence of the UL148C putative protein. Isolates that have been passaged several times in human embryonic lung fibroblasts (HELF) showed some changes of modification sites, however. A discrete linkage was found between the groups of UL148A gene and those of UL148D gene.

High variability of human cytomegalovirus UL150 open reading frame in low-passaged clinical isolates.

OBJECTIVE: To investigate the polymorphism of human cytomegalovirus (HCMV) UL150 open reading frame (ORF) in low-passaged clinical isolates, and to study the relationship between the polymorphism and different pathogenesis of congenital HCMV infection. METHODS: PCR was performed to amplify the entire HCMV UL150 ORF region of 29 clinical isolates, which had been proven containing detectable HCMV-DNA using fluorescence quantitative PCR. PCR amplification products were sequenced directly, and the data were analyzed. RESULTS: Totally 25 among 29 isolates were amplified, and 18 isolates were sequenced successfully. HCMV UL150 ORF sequences derived from congenitally infected infants were high variability. The UL150 ORF in all 18 clinical isolates shifted backward by 8 nucleotides leading to frame-shift, and contained a single nucleotide deletion at nucleotide position 226 compared with that of Toledo strain. The nucleotide diversity was 0.1% to 6.8% and the amino acid diversity was 0.2% to 19.2% related to Toledo strain. However, the nucleotide diversity was 0.1% to 6.4% and amino acid diversity was 0.2% to 8.3% by compared with Merlin strain. Compared with Toledo, 4 new cysteine residues and 13 additional posttranslational modification sites were observed in UL150 putative proteins of clinical isolates. Moreover, the UL150 putative protein contained an additional transmembrane helix at position of 4-17 amino acid related to Toledo. CONCLUSION: HCMV UL150 ORF and deduced amino acid sequences of clinical strains are hypervariability. No obvious linkage between the polymorphism and different pathogenesis of congenital HCMV infection is found.

[Variability of human cytomegalovirus UL144 gene in low-passage clinical isolates analyzed by HMA-SSCP].

BACKGROUND: Human cytomegalovirus (HCMV) infection is an important infectious agent that results in neonatal disease and congenital deformity. HCMV infection may affect in many organs. The different symptoms and tissue tropism of HCMV infection perhaps resulted from the genetic polymorphism of HCMV. HCMV UL144 open reading frames encode a homologue of the tumor necrosis factor receptor. It seems important to study the strain-specific variability of UL144 sequence in low-passage clinical isolates and to discuss if the variability related to the clinical HCMV infection. METHODS: HCMV-UL144 gene was amplified by PCR assay in 65 low-passage clinical isolates and urine from 7 healthy children who were HCMV-DNA positive by quantitative PCR. All the positive PCR products were analyzed by Heteroduplex mobility assay and single-stranded conformation polymorphism (HMA-SSCP) and 32 of them were sequenced. RESULTS: Fifty-five isolates and 5 urine specimens were HCMV-UL144 positive by PCR. Sequencing and HMA-SSCP analysis showed that significant strain-specific variability was present in the UL144 ORFs. Comparing UL144 sequences and the corresponding symptoms showed that genotype 2 did not exist in megacolon isolates. And genotype 1 and 3 were the major types among microcephaly and jaundice isolates respectively. CONCLUSION: HCMV-UL144 existed in almost all the low passage isolates. HMA-SSCP assay is an easy and effective method to detect the genetype of HCMV-UL144 sequence. The characteristic of sequences in different isolates showed that UL144 gene may play an important role in HCMV infection.

[Polymorphisms of HCMV US28 gene of the clinical isolates from children].

BACKGROUND: To study the polymorphism of human cytomegalovirus US28 gene in children and investigate the relationship between the polymorphism and pathogenesis. METHODS: The FQ-PCR was carried out to determine the DNA quantity of clinical isolate and then the segmental PCR and HMA-SSCP were performed to test the mutation of US28 gene. The typical isolates from different diseases were selected to clone and sequence, then the results were analyzed. RESULTS: The nucleic acid mutation is frequent among the sequence of US28, those mutations focus on the two ends of US28, but most of them are sense mutation. The important functional groups of US28 are highly conserved. The amino acid mutation of some isolates resulted in the change of secondary structure, but the phylogenetic tree analysis did not show any clear association between the pathogenesis and the distribution of clinical isolates. The comparison of US28 sequences from AIDS patients with the sequences from children in our study showed that both sequences have their own specific high mutation points. CONCLUSION: There is polymorphism among the HCMV-US28 gene of clinical isolates from children. There observed no clear relationship was between the pathogenesis and the distribution of clinical isolates.

Sequence variability of human cytomegalovirus UL143 in low-passage clinical isolates.

BACKGROUND: Human cytomegalovirus (HCMV) infects a number of organs and tissues in vivo. The different symptoms and tissue tropisms of HCMV infection perhaps result from genetic polymorphism. A new region of DNA containing at least 19 open reading frames (ORFs) (denoted UL133 to 151) was found in the low-passage HCMV clinical strain, Toledo, and several other low-passage clinical isolates, but not present in the HCMV laboratory strain, AD169. One of these genes, UL143, was studied to explore the sequence variability of UL143 ORF in HCMV clinical isolates and examine the possible association between gene variability and the outcome of HCMV infection. METHODS: The UL143 gene of the strains obtained from suspected congenitally HCMV-infected infants was amplified by polymerase chain reaction (PCR) and sequenced. RESULTS: Nineteen sequences of the strains were divided into 2 major groups, G(1) (n = 16) and G(2) (n = 3). All of the sequences had frame-shift mutation compared to Toledo. Nucleotide polymorphisms conferred substantial amino acid substitutions when compared with Toledo. All 16 UL143 putative proteins of the strains in G(1) had a new myristylation site and loss of two PKC sites owing to missense mutations. No convincing relationships were observed between the presence of HCMV disease and the UL143 sequence group. CONCLUSIONS: HCMV-UL143 existed in low passage isolates. Sequence variability caused by frame-shift mutation was found in all HCMV clinical strains. No obvious linkage was observed between UL143 polymorphisms and the outcome of suspected congenital HCMV infection.

Sequence variability of human cytomegalovirus UL146 and UL147 genes in low-passage clinical isolates.

OBJECTIVES: Human cytomegalovirus (HCMV) infects a number of organs and cell types in vivo. The different symptoms and tissue tropisms of HCMV infection perhaps result from the genetic polymorphism. A new region of DNA containing at least 19 open reading frames (ORFs - denoted UL133-151) was found in the low-passage HCMV clinical strain Toledo and several other low-passage clinical isolates, but not present in the HCMV laboratory strain AD169. Two of these genes, UL146 and UL147, encode proteins with sequence characteristics of CXC (alpha) chemokines, suggesting that they might influence the behavior of neutrophils during infection. This research was to study the sequence variability of UL146 and UL147 ORFs in HCMV clinical isolates and examine the possible associations between gene variability and the outcome of HCMV infection. METHODS: UL146 and UL147 genes from strains obtained from suspected congenitally HCMV-infected infants were PCR amplified and sequenced. RESULTS: High variability was found in UL146 and UL147 gene among HCMV clinical strains. However, the alpha chemokine motif in UL146 and UL147 genes was conserved in almost all sequences. According to the phylogenetic analysis, all sequences of UL146 in clinical isolates could be divided into three groups. All strains from congenital megacolon infants existed in G2A only, and all from asymptomatic infants existed in G2B peculiarly. CONCLUSIONS: Sequence variability among HCMV clinical strains may affect the ability of UL146 and UL147 to attract human neutrophils and influence viral dissemination. No obvious linkage was observed between UL146 polymorphisms and outcome of suspected congenital HCMV infection.

Human cytomegalovirus (HCMV) UL139 open reading frame: Sequence variants are clustered into three major genotypes.

Human cytomegalovirus (HCMV) infects a number of organs and cell types, leading to the hypothesis that HCMV disease and tissue tropism may be related to specific sequence variability. This study examined the genomic variability of a new polymorphic locus in HCMV, UL139 open reading frame (ORF). Detailed analysis showed that a large number of nucleotide insertions and non-synonymous substitutions occurred in the UL139 ORF, particularly in the 5' half, using the Toledo strain as the reference sequence. The UL139 variants were not distributed randomly, but were clustered clearly into three major groups: G1 (G1a, G1b, and G1c), G2 (G2a, G2b), and G3. In this study, it was found that the predicted UL139 product shared sequence homology with human CD24, a signal transducer modulating B-cell activation responses, and the sequences in G1c contained a specific attachment site of prokaryotic membrane lipoprotein lipid. The precise definition of UL139 genotypes and its putative function would be helpful in understanding better HCMV.

Structure and variability of the UL149 open reading frame from low-passage clinical isolates of human cytomegalovirus.

Human cytomegalovirus (HCMV), a ubiquitous herpesvirus, causes a lifelong subclinical infection in healthy adults but leads to significant morbidity and mortality in neonates and immunocompromised individuals. A region (referred to as UL/b') present in the Toledo strain of HCMV and low passage clinical isolates contains 19 additional genes, which are absent in the highly passage laboratory strain AD169. One of these genes, UL149 open reading frame, was amplified by PCR and sequenced from isolates obtained from infants with congenital HCMV infection, to determine whether genetic variation of this gene could influence the signs of the virus infection. The major finding is that the UL149 is a variable gene in all 26 clinical isolates, and the sequences from clinical isolates were classified into three major groups. It is concluded that the HCMV UL149 sequence is variable at the nucleotide level and it might play an important role in HCMV infection.