RESUMEN
Stroke is the most common cerebrovascular disease, the second leading cause of death behind heart disease and is a major cause of long-term disability worldwide. Currently, systemic immunomodulatory therapy based on intravenous cells is attracting attention. The immune response to acute stroke is a major factor in cerebral ischaemia (CI) pathobiology and outcomes. Over the past decade, the significant contribution of the spleen to ischaemic stroke has gained considerable attention in stroke research. The changes in the spleen after stroke are mainly reflected in morphology, immune cells and cytokines, and these changes are closely related to the stroke outcomes. Autonomic nervous system (ANS) activation, release of central nervous system (CNS) antigens and chemokine/chemokine receptor interactions have been documented to be essential for efficient brain-spleen cross-talk after stroke. In various experimental models, human umbilical cord blood cells (hUCBs), haematopoietic stem cells (HSCs), bone marrow stem cells (BMSCs), human amnion epithelial cells (hAECs), neural stem cells (NSCs) and multipotent adult progenitor cells (MAPCs) have been shown to reduce the neurological damage caused by stroke. The different effects of these cell types on the interleukin (IL)-10, interferon (IFN), and cholinergic anti-inflammatory pathways in the spleen after stroke may promote the development of new cell therapy targets and strategies. The spleen will become a potential target of various stem cell therapies for stroke represented by MAPC treatment.
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Bazo/fisiología , Trasplante de Células Madre/métodos , Accidente Cerebrovascular/cirugía , Animales , Citocinas/metabolismo , HumanosRESUMEN
BACKGROUND: Increased expression of transcriptional coactivator p300 has been observed in a variety of human cancers. However, the expression status of p300 protein/mRNA in nasopharyngeal carcinoma (NPC) tissues and its clinicopathologic/prognostic implication are poorly understood. METHODS: In our study, mRNA and protein expression levels of p300 was explored by reverse transcription-polymerase chain reaction (RT-PCR), Western blotting (WB) and immunohistochemistry (IHC) in nasopharyngeal mucosal and NPC tissues. The data were analyzed by receiver operating characteristic (ROC) curve analysis, spearman's rank correlation, Kaplan-Meier plots and Cox proportional hazards regression model. RESULTS: Up-regulated expression of p300 mRNA/p300 protein was detected in NPC tissues by RT-PCR and WB, when compared to nasopharyngeal mucosal tissues. Based on ROC curve analysis, the cutoff score for p300 high expression was defined when more than 35% of the tumor cells were positively stained. High expression of p300 was observed in 127/209 (60.7%) of NPCs. In NPCs, high expression of p300 was positively associated with later T classification, later N classification, distant metastasis and later clinical stage (P < 0.05). In univariate survival analysis, overexpression of p300 was found to be an indicator of progression-free (P = 0.002) and overall survival (P = 0.001) in NPCs. More importantly, p300 expression was evaluated as an independent prognostic factor for NPC in multivariate analysis (P = 0.036). CONCLUSIONS: Our findings support that high expression of p300 protein might be important in conferring a more aggressive behavior, and is an independent molecular marker for shortened survival time of patients with NPC.
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Neoplasias Nasofaríngeas/metabolismo , Factores de Transcripción p300-CBP/metabolismo , Western Blotting , Carcinoma , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/enzimología , Neoplasias Nasofaríngeas/patología , Pronóstico , Curva ROC , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de SupervivenciaRESUMEN
Mtsarg1 (Mus musculus testis and spermatogenesis cell apoptosis-related gene 1) gene with 1103 bp in full length had been cloned previously (GenBank accession number: AF399971, 2002; re-designated as Spata3, Mus musculus spermatogenesis-associated 3, 2007). In the present study, we identified a novel transcript variant of Mtsarg1, named Mtsarg1-beta which is 887 bp in length (GenBank accession numbers: EU259321 and EF546784, 2007, designated as Spata3 variant 4) by reverse transcription-polymerase chain reaction (RT-PCR), cloning and sequencing. Mtsarg1-beta which has high similarity with Mtsarg1 contains an entire open reading frame of 417 bp encoding a protein consisting of 138 amino acids. Mtsarg1-beta protein is a non-secretory protein with a theoretic molecular mass around 14.79 kD and an isoelectric point of 9.74, which shares the 100 N-terminal amino acids with Mtsarg1 followed by 38 amino acids differing from Mtsarg1. Multi-tissue RT-PCR results and Northern blot analysis for adult DBA/2 mice showed that Mtsarg1-beta and Mtsarg1 mRNAs were specifically expressed in testis at high level. RT-PCR results also showed that Mtsarg1-beta and Mtsarg1 mRNAs were not expressed in mouse GC-1 spermatogonia. In situ hybridization revealed that both Mtsarg1 and probably Mtsarg1-beta mRNAs were mainly expressed in mouse spermatocytes. Subcellular localization analysis suggested that Mtsarg1 protein was mainly localized in nucleus while Mtsarg1-beta protein was mainly localized in cytoplasm. All these results indicate that Mtsarg1 and Mtsarg1-beta may play an important role in mouse testicular function and in spermatocyte development.
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Proteínas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Clonación Molecular , Biología Computacional , ADN Complementario/genética , Exones/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Hibridación in Situ , Intrones/genética , Masculino , Ratones , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transporte de Proteínas , Proteínas/química , Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Espermatogonias/metabolismo , Fracciones Subcelulares/metabolismoRESUMEN
AIM: To analyze indications and reasons for failure of anterior lamellar keratoplasty (ALK). METHODS: The clinical records were retrospectively reviewed. Main outcome measures included indications for ALK and reasons for failure of ALK. RESULTS: A total of 434 patients (462 eyes) were treated with ALK at Qingdao Eye Hospital, Shandong Eye Institute from June 1, 2009 to May 31, 2016. The main indications were infectious keratitis (33.3%), keratoconus (23.6%), corneal dystrophy and degeneration (9.8%), Mooren's ulcer (8.4%), corneal neoplasm (7.8%), viral keratitis (6.5%) and regrafting (3.7%). Fungal keratitis accounted for 73.4% in the infectious keratitis cases. ALKs were failed in 36 patients, with the major causes being recurrence of primary diseases (63.9%). The leading causes of graft failure was Mooren's ulcer (36.1%), followed by infectious keratitis (30.6%). Recurrence of fungal keratitis accounted for 81.8% in the failed cases after ALK for infectious keratitis cases. CONCLUSION: Infectious keratitis and keratoconus are the main indications for ALK, of which fungal keratitis was the major cause of corneal infections. Recurrence of primary disease is the main reason of graft failure after ALK, in which the main primary diseases associated with graft failure are Mooren's ulcer and fungal keratitis.
RESUMEN
A novel human gene TSARG7 (GenBank accession No. AY513610) was identified from a human testis cDNA library by using the mTSARG7 gene (GenBank accession No. AY489184) as an electronic probe. The gene whose full cDNA length is 2,463 bp containing 12 exons and 11 introns is located in the human chromosome 8p11.21. The predicted protein encoded by this gene contains 456 amino acids with a theoretical molecular weight of 56,295 dalton and isoelectric point of 9.13. It is a new member of the acyltransferase family since its sequence possesses the highly conserved PlsC domain existing in all acyltransferase-like proteins. Two groups, the TSARG7 and mTSARG7, the TSARG7 and Au041707, share 97% identity in the 456 amino acids. Expression of the TSARG7 gene is restricted to the testis. Subcellular localization studies show that the EGFP-tagged TSARG7 protein was localized in the cytoplasm of GC-1 cells. The TSARG7 mRNA expression was initiated in the testis of a 13-year-old boy, and its level increased steadily along with spermatogenesis and sexual maturation of the human. The results of heat stress experiment demonstrate that TSARG7 expression has a relation with temperature. In conclusion, our study suggests that we have cloned a novel human gene and this gene may play an important role in human spermatogenesis and sexual maturation.
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ADN Complementario/genética , Glicerol-3-Fosfato O-Aciltransferasa/genética , Espermatogénesis/genética , Testículo/metabolismo , Adolescente , Adulto , Anciano , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromosomas Humanos Par 8 , Clonación Molecular , Citoplasma/metabolismo , Feto , Glicerol-3-Fosfato O-Aciltransferasa/biosíntesis , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Proteínas Oncogénicas/genética , Sistemas de Lectura Abierta , ARN Mensajero/metabolismo , Maduración Sexual/genética , Temperatura , Testículo/crecimiento & desarrolloRESUMEN
In this study, a new data mining tool called Digital Differential Display (DDD) from the NCBI was used to predict testis-specific expressed genes from the expressed sequence tag (EST) database. DDD (digital differential display) was performed between nine testis libraries and seventy libraries derived from other tissues. We identified a new contig of ESTs (HS. 326528) which was from testis libraries. To validate the use of bioinformatic approaches in gene discovery, the ESTs (HS. 326528), which were predicted to be testis-specific, were chosen for further study. Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) analysis of matched sets of cDNAs from testis and other tissues indicated that the ESTs were specifically expressed in testis. This result was further validated by multi-tissue Northern blot. The full-length cDNA encompassing the entire open reading frame was cloned and, in view of its apparent specificity to testis, the gene was termed homo sapiens spermatogenesis-related gene 8---SRG8 (GenBank accession number: AY489187). The gene whose full cDNA length is 1 044 bp containing 3 exons and 2 introns is located in human chromosome 15q26.2, the cDNA encodes a novel protein of 105 amino acides with a theoretical molecular weight of 11.7 kD and isoelectric point of 10.09 which shares no significant homology with any known proteins in database. Real time PCR analysis of testis of different developmental periods revealed that SRG8 gene is significantly expressed in adult testis. The green fluorescent protein produced by pEGFP-C3/SRG8 was detected in the nucleus of HeLa cells after 24 h post-transfection. Cell cycle analysis showed that SRG8 can accelerate HeLa cells to traverse the S-phase and enter the G2-phase compared with the control without transfection of SRG8, which suggested that this gene plays an important role in the development of testis. The discovery of SRG8 showed that DDD combined with experiments is a feasible, time-saving strategy to identify new candidate genes for testis-specific development
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Proteínas de Ciclo Celular/genética , Proteínas Nucleares/genética , Espermatogénesis/genética , Testículo/metabolismo , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Ciclo Celular/genética , Ciclo Celular/fisiología , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Proliferación Celular , Cromosomas Humanos Par 15 , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica , Biblioteca de Genes , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Microscopía Confocal , Datos de Secuencia Molecular , Proteínas Nucleares/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , TransfecciónRESUMEN
cDNA microarray is a powerful tool to analyze simultaneously the expression levels of tens of thousands of genes. Compared with normal nasopharynx (NP) tissues, 2210 genes were highly differentially expressed in nasopharyngeal carcinoma (NPC) tissues detected by cDNA microarray. Since signal pathway is widely used to describe the complex relationship between genes, a pathway-based network was constructed to visualize the connection between the genes obtained from microarray data in this report. We analyzed the targeted genes that may have more important influence on this gene network with statistical methods and found that some genes might have significant influence on this network, especially Ras-related nuclear protein (RAN), carboxyl ester lipase (CEL), v-rel reticuloendotheliosis viral oncogene homolog A (RELA) genes. To verify the results from pathway-based selection, reverse transcription-polymerase chain reaction (RT-PCR) and real-time RT-PCR were performed to detect the expression levels of RAN, CEL and RELA genes and it was found that the RAN and CEL genes were significantly up-regulated in more than 80% of NPC tissues. To further elucidate the function of the RAN gene, RAN expression was specifically suppressed in a 5-8F NPC cell line by RNA interference (RNAi). As expected, the depletion of RAN could effectively block the proliferation of tumor cells. Therefore, our study may open up a new way to analyze the vast microarray data.
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Carcinoma/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Nasofaríngeas/genética , Proteína de Unión al GTP ran/genética , Secuencia de Bases , Western Blotting , Ciclo Celular , Línea Celular Tumoral , Humanos , Modelos Biológicos , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sales de Tetrazolio/farmacología , Tiazoles/farmacología , TransfecciónRESUMEN
OBJECTIVE: To understand the genotypic mapping of Mycobacterium leprae identified in China and to compare with those from other countries to select suitable alleles for epidemiological investigation in the transmission chain of leprosy. METHODS: Various number of tandem repeat(VNTR) in genomic DNA of Mycobacterium leprae was used in the present genotyping study. 33 skin biopsies from Wenshan prefecture,Yunnan province and 17 from other parts of China were studied. DNA extracted from skin biopsies of leprosy patients was subjected to PCR followed by agarose gel analysis and DNA sequencing to determine the number of repeats. RESULTS: Loci GGT-5,12-5,21-3 and 23-3 were as highly homogenous as 100%; The homogeneity of loci AC-8, 18-8, 27-5 and rpoT were 97%, 94%, 97% and 85% respectively. Loci GTA-9, AC-9 and 6-7 showed significant allelic diversity in isolates and the diversity of GTA-9 in Mycobacterium leprae isolated from China was also different from those identified other countries. We had subjected loci GTA-9 and the ten loci to phylogenetic tree analysis respectively. CONCLUSION: The present study revealed that the genotype of Mycobacterium leprae identified from China was close to the strains from the Philippines and India although a few loci were somehow differentiate. Locus 12-5 manifested as only 3 copies in China whereas 4-5 copies predominating in other countries. 12-5 locus might serve as a useful marker to diffrentiate Chinese strains from those in other countries. However, further study on the diversity of GTA-9 was needed in China. The molecular typing of Mycobacterium leprae from different geographic areas might be useful in studying the transmission of leprosy.
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Lepra/epidemiología , Mycobacterium leprae/genética , Mycobacterium leprae/aislamiento & purificación , Alelos , China/epidemiología , ADN Bacteriano , Genotipo , Humanos , Lepra/transmisión , Epidemiología Molecular , Reacción en Cadena de la Polimerasa , Piel/microbiologíaRESUMEN
Cystatins are cysteine proteinase inhibitors. We found two expression sequence tags (ESTs), CA463109 and AV042522, from a mouse testis library using Digital differential display (DDD). By electrical hybridization, a novel gene, Cymg1 (GenBank accession No. AY600990), which has a full length of 0.78 kb, and contains four exons and three introns, was cloned from a mouse testis cDNA library. The gene is located in the 2G3 area of chromosome 2. The full cDNA encompasses the entire open reading frame, encoding 141 amino acid residues. The protein has a cysteine protease inhibitor domain that is related to the family 2 cystatins but lacks critical consensus sites important for cysteine protease inhibition. These characteristics are seen in the CRES subfamily, which are related to the family 2 cystatins and are expressed specifically in the male reproductive tract. CYMG1 has a 44% (48/108) identity with mouse CRES and 30% (42/140) identity with mouse cystatin C. Northern blot analysis showed that the Cymg1 is specifically expressed in adult mouse testes. Cell location studies showed that the GFP-tagged CYMG1 protein was localized in the cytoplasm of HeLa cells. Immunohistochemistry revealed that the CYMG1 protein was expressed in mouse testes spermatogonium, spermatocytes, round spermatids, elongating spermatids and spermatozoa. RT-PCR results also showed that Cymg1 was expressed in mouse testes and spermatogonium. The Cymg1 expression level varied in different developmental stages: it was low 1 week postpartum, steadily increased 2 to 5 weeks postpartum, and was highest 7 weeks postpartum. The expression level at 5 weeks postpartum was maintained during 13 to 57 weeks postpartum. The Cymg1 expression level in the testes over different developmental stages correlates with the mouse spermatogenesis and sexual maturation process. All these indicate that Cymg1 might play an important role in mouse spermatogenesis and sexual maturation.
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Cistatinas/genética , Cistatinas/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Clonación Molecular , Biología Computacional , Inhibidores de Cisteína Proteinasa/farmacología , ADN Complementario/metabolismo , Escherichia coli/metabolismo , Exones , Etiquetas de Secuencia Expresada , Biblioteca de Genes , Células Germinativas/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Células HeLa , Humanos , Inmunohistoquímica , Intrones , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Plásmidos/metabolismo , Reacción en Cadena de la Polimerasa , ARN/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Espermatogénesis , Temperatura , Testículo/metabolismo , Testículo/patología , TransfecciónRESUMEN
A novel testis-specific gene termed mtLR1 was identified by digital differential display. Sequence analyses revealed that mtLR1 protein contains an amino terminus leucine-rich repeat domain and shows 33% similarities to PIDD which functions in p53-mediated apoptosis. Northern blot analysis showed that mtLR1 mRNA was specifically expressed in adult mouse testis, and RT-PCR results also showed that mtLR1 was exclusively expressed in adult testis and not in spermatogonial cells. The expression of mtLR1 mRNA was developmentally upregulated in the testes during sexual maturation and was, conversely, downregulated by experimental cryptorchidism in vivo. We also showed that the expression of mtLR1 mRNA was relatively highly sensitive to heat stress in vitro. The green fluorescent protein produced by pEGFP-C3/mtLR1 was only detected in the cytoplasm of spermatogonia cell line GC-1 after 24 h posttransfection. Immunohistochemical analysis revealed that the protein is most abundant in the cytoplasm of spermatocytes and round spermatids within seminiferous tubules of the adult testis. The time-dependent expression pattern of mtLR1 in postnatal mouse testes suggested that mtLR1 gene might be involved in the regulation of spermatogenesis and sperm maturation.
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Envejecimiento/metabolismo , Criptorquidismo/metabolismo , Trastornos de Estrés por Calor/metabolismo , Proteínas/metabolismo , Espermatogénesis , Testículo/metabolismo , Secuencia de Aminoácidos , Animales , Femenino , Regulación del Desarrollo de la Expresión Génica , Masculino , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Proteínas/química , Homología de Secuencia de Aminoácido , Distribución TisularRESUMEN
Beginning with a new contig of the expressed sequence tags (Mm.63892) obtained by comparing testis libraries with other tissue and cell line libraries using the digital differential display program, we cloned a new gene which is related to the apoptosis of mouse spermatogenic cells using the Genscan program and polymerase chain reaction (PCR) technology. The sequence data have been submitted to the GenBank database under accession number AY747687. The full cDNA length is 1074 bp, and the gene with 7 exons and 6 introns is located in mouse chromosome 1 H5. The protein is recognized as a new member of calmodulin (CaM) binding protein family because the sequence contains three short calmodulin-binding motifs containing conserved Ile and Gln residues (IQ motif) and is considered to play a critical role in interactions of IQ motif-containing proteins with CaM proteins. The putative protein encoded by this gene has 192 amino acid residues with a theoretical molecular mass of 23.7 kDa and a calculated isoelectric point of 9.71. The sequence shares no significant homology with any known protein in databases. RT-PCR and Northern blot analyses revealed that 1.3 kb MSRG-11 transcript was strongly expressed in adult mouse testis but weakly expressed in the spleen and thymus. The MSRG-11 gene was expressed at various levels, faintly at two weeks postpartum and strongly from three weeks postpartum in adult testes. The green fluorescence produced by pEGFP-C2/MSRG-11 was detected in the cytoplasm of COS7 cells 24 h post-transfection. The pcDNA3.1(?-)/MSRG-11 plasmid was constructed and introduced into COS7 cells using Lipofectamine 2000 transfection reagent (Invitrogen, Carlsbad, USA). MSRG-11 can accelerate COS7 cell apoptosis, which suggests that this gene may play an important role in the development of mouse testes and is a candidate gene of testis-specific apoptosis. Based on these observations, it was considered that we cloned a new gene which probably accelerates spermatogenetic cell apoptosis in mouse.
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Apoptosis/fisiología , Proteínas de Unión a Calmodulina/genética , Proteínas de Unión a Calmodulina/metabolismo , Clonación Molecular/métodos , Espermatozoides/metabolismo , Testículo/metabolismo , Secuencia de Aminoácidos , Animales , Células COS , Proteínas de Unión a Calmodulina/química , Chlorocebus aethiops , Perfilación de la Expresión Génica , Masculino , Ratones , Datos de Secuencia Molecular , Especificidad de Órganos , Proteínas Recombinantes/metabolismo , Distribución TisularRESUMEN
A novel mouse gene, mTSARG7 (GenBank accession No. AY489184), with a full cDNA length of 2279 bp and containing 12 exons and 11 introns, was cloned from a mouse expressed sequence tag (GenBank accession No. BE644543) that was significantly up-regulated in cryptorchidism. The gene was located in mouse chromosome 8A1.3 and encoded a protein containing 403 amino acid residues that was a new member of the acyltransferase family because the sequence contained the highly conserved phosphate acyltransferase (PlsC) domain existing in all acyltransferase-like proteins. The mTSARG7 protein and AU041707 protein shared 83.9% identity in 402 amino acid residues. Expression of the mTSARG7 gene was restricted to the mouse testis. The results of the in situ hybridization analysis revealed that the mTSARG7 mRNA was expressed in mouse spermatogonia and spermatocytes. Subcellular localization studies showed that the EGFP-tagged mTSARG7 protein was localized in the cytoplasm of GC-1 spg cells. The mTSARG7 mRNA expression was initiated in the mouse testis in the second week after birth, and the expression level increased steadily with spermatogenesis and sexual maturation of the mouse. The results of the heat stress experiment showed that the mTSARG7 mRNA expression gradually decreased as the heating duration increased. The pcDNA3.1 Hygro(-)/mTSARG7 plasmid was constructed and introduced into GC-1 spg cells by liposome transfection. The mTSARG7 can accelerate GC-1 spg cells, causing them to traverse the S-phase and enter the G2-phase, compared with the control group where this did not occur as there was no transfection of mTSARG7. In conclusion, our results suggest that this gene may play an important role in spermatogenesis and the development of cryptorchid testes, and is a testis-specific apoptosis candidate oncogene.
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Apoptosis , Proteínas Oncogénicas/genética , Oncogenes , Espermatogénesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Western Blotting , Línea Celular , Clonación Molecular , Biología Computacional , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Proteínas Oncogénicas/biosíntesis , Proteínas Oncogénicas/química , Reacción en Cadena de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Testículo/metabolismo , Distribución TisularRESUMEN
Spermatogenesis is a complex process. Two spermatocytes expression sequence tags (ESTs) BG101130 and BG100990 were found. Their putative amino acid sequences have high homology with rat Spag4 (sperm antigen 4). By electrical hybridization, a novel cDNA encoding polypeptide of 348 amino acid residues was identified from a mouse testis cDNA library. The new gene was designated as SRG4 (Spermatogenesis related gene 4) (GenBank accession No. AY307077). Results of Northern blot and RTPCR revealed that SRG4 expressed specifically in mouse testis. Changes of SRG4 expression in mouse different development stages were observed by RT-PCR. The SRG4 mRNA was hardly detected in 2 weeks postpartum, and expressed abundantly from 3 weeks later, reaching top lever at 4-5 weeks, while slightly down in aging mouse testis. Results of in situ hybridization showed that SRG4 gene expressed abundantly in spermatocytes, round spermatids. This indicated SRG4 gene may play an important role in mouse meiotic divisions of spermatocytes.