WDR87 interacts with CFAP47 protein in the middle piece of spermatozoa flagella to participate in sperm tail assembly

Spermatogenesis is a complex process that includes spermatogonia self-renewal, spermatocyte meiosis and spermatozoa assembly. Recent studies have revealed that WD40-repeat domain-containing (WDR) proteins play important roles in spermatocyte division, spermatozoa flagella assembly and head shaping. In this study, we investigated the expression pattern of WDR87 and found that it was highly expressed in the testis of both humans and mice. Immunofluorescence staining revealed that mouse WDR87 was distributed in the perinuclear cytoplasm of primary spermatocytes, secondary spermatocytes and round spermatids. In the spermiogenesis stage, with extension of the nucleus, WDR87 migrated to the manchette and finally localized to the middle piece of the spermatozoa tail. Furthermore, we identified a cilia- and flagella-associated protein, CFAP47, which interacted with WDR87 in the flagellar midpiece of the spermatozoa, suggesting that WDR87 may be associated with multiple morphological abnormalities of the flagella (MMAF). Subsequently, we screened gene mutations in seven MMAF individuals and found two novel mutations in CFAP47 (c.706G>A, Val236Met; c.1337C>T, Thr446Met) in one case. Immunoblotting and immunofluorescence revealed that CFAP47 was dramatically reduced in spermatozoa from the CFAP47-mutated man. Meanwhile, the expression of WDR87 was also significantly decreased, and weak signals were detected adjacent to the spermatozoa nuclei, indicating that CFAP47 was necessary for WDR87 transportation during spermatozoa flagella biogenesis. These data indicate that WDR87 is located in the middle piece of the sperm tail and interacts with CFAP47 to form a complex which is involved in spermatozoa tail assembly.

Metagenomic Next-Generation Sequencing of Cerebrospinal Fluid for the Diagnosis of Cerebral Aspergillosis

Purpose: Cerebral aspergillosis (CA) is a rare but often fatal, difficult-to-diagnose, opportunistic infection. The utility of metagenomic next-generation sequencing (mNGS) for diagnosis of CA is unclear. We evaluated the usefulness of mNGS of the cerebrospinal fluid (CSF) for the diagnosis of CA. Methods: This prospective study involved seven consecutive patients with confirmed CA in whom CSF mNGS was performed. Serum (1→3)-β-D-glucan and galactomannan levels were determined, and histopathological examination and mNGS of the CSF were conducted. CSF specimens from three non-infected patients were used as positive controls. Results: mNGS of the CSF was positive in six of the seven confirmed CA cases (85.71% sensitivity). In the cryptococcal meningitis group (control), mNGS of the CSF was positive for Aspergillus in two patients (84.62% specificity). The positive likelihood ratio, negative likelihood ratio, and Youden's index of mNGS for CA in the CSF were 5.565, 0.169, and 0.7, respectively. Among the six mNGS-positive cases, more than two Aspergillus species were found in four (4/6, 66.67%). In the positive controls, the addition of one A. fumigatus spore yielded a standardised species-specific read number (SDSSRN) of 25.45 by mNGS; the detection rate would be 0.98 if SDSSRN was 2. Conclusion: mNGS facilitates the diagnosis of CA and may reduce the need for cerebral biopsy in patients with suspected CA. Trial Registration Number: Chinese Clinical Trial Registry, ChiCTR1800020442.

Rat BAT xenotransplantation recovers the fertility and metabolic health of PCOS mice

Polycystic ovarian syndrome (PCOS) is a major severe ovary disorder affecting 5-10% of reproductive women around the world. PCOS can be considered a metabolic disease because it is often accompanied by obesity and diabetes. Brown adipose tissue (BAT) contains abundant mitochondria and adipokines and has been proven to be effective for treating various metabolic diseases. Recently, allotransplanted BAT successfully recovered the ovarian function of PCOS rat. However, BAT allotransplantation could not be applied to human PCOS; the most potent BAT is from infants, so voluntary donors are almost inaccessible. We recently reported that single BAT xenotransplantation significantly prolonged the fertility of aging mice and did not cause obvious immunorejection. However, PCOS individuals have distinct physiologies from aging mice; thus, it remains essential to study whether xenotransplanted rat BAT can be used for treating PCOS mice. In this study, rat-to-mouse BAT xenotransplantation, fortunately, did not cause severe rejection reaction, and significantly recovered ovarian functions, indicated by the recovery of fertility, oocyte quality, and the levels of multiple essential genes and kinases. Besides, the blood biochemical index, glucose resistance, and insulin resistance were improved. Moreover, transcriptome analysis showed that the recovered PCOS F0 mother following BAT xenotransplantation could also benefit the F1 generation. Finally, BAT xenotransplantation corrected characteristic gene expression abnormalities found in the ovaries of human PCOS patients. These findings suggest that BAT xenotransplantation could be a novel therapeutic strategy for treating PCOS patients.

Sporadic Creutzfeldt-Jakob Disease: A Retrospective Analysis of 104 Cases

BACKGROUND

Sporadic Creutzfeldt-Jakob disease (sCJD) is an extremely rare fatal and infectious neurodegenerative brain disorder characterized by rapidly progressive dementia, cerebellar ataxia, and visual disturbances. This article summarizes the retrospective analysis of 104 sCJD patients in the First Medical Center of Chinese PLA General Hospital from 2003 to 2019.

METHODS

A retrospective analysis of the medical records of the 104 patients diagnosed with sCJD was performed from the aspects of demographic data, clinical manifestations, laboratory examinations, cerebrospinal fluid analysis, electroencephalograms (EEGs), diffusion-weighted imaging (DWI) scans, positron emission tomography (PET) scans, and prion protein gene mutations.

RESULTS

In the 104 sCJD patients, pathological evidence of a spongiform change was found in 11 patients, while the remaining 93 patients were probable sCJD. The 104 patients included 57 males and 47 females, with the age of onset ranging from 29 to 82 (mean: 58, median: 60) years. The time from disease onset to death ranged from 1 to 36 months. Most of the patients died 7-12 months after the onset of sCJD. In most patients, rapidly progressive dementia appeared as the initial symptom, followed by cerebellar ataxia, visual disturbances, and neurobehavioral disorders. Most patients' DWI images showed symmetric or asymmetric hyperintensity in the cortex. In terms of EEGs, 38.2% of the patients had periodic sharp wave complexes. The sensitivity of 14-3-3 protein detection was 34.1%. The brain PET scans of 50 patients with sCJD presented 96% sensitivity for the diagnosis of sCJD.

CONCLUSIONS

This study indicated that sCJD occurred at an early age in patients in China. The sensitivity of 14-3-3 protein detection was significantly low, but brain PET was highly sensitive in the diagnosis of sCJD.

Glutamate dehydrogenase inhibits tumor growth in gastric cancer through the Notch signaling pathway

Glutamate dehydrogenase (GDH) is a key enzyme in glutaminolysis and can regulate allosteric functions. Immunohistochemical study found that GDH expressed in gastric cancer cell cytoplasm and membrane, and a few located in the nucleus, ranging from light yellow to tan to sepia. According to the analysis by Kaplan Meier survival curve and the Log-Rank test, the median survival of GDH high expression in patients was 51.7 months with 95% confidence intervals (CI) was 41.138-55.262. The expression level of GDH was significantly reduced after silencing GDH gene in gastric cancer cells and tissues. Further, after silencing GDH gene, gastric cancer cell migration and invasion ability were decreased significantly. Protein expression of. In addition, tumor growth was significantly reduced after silencing GDH gene. In vivo and in vitro experiments suggest that GDH can decrease gastric cancer cell migration and invasion, thus inhibiting tumor growth.

Metagenomic Next-Generation Sequencing for Diagnosis of Infectious Encephalitis and Meningitis: A Large, Prospective Case Series of 213 Patients

Purpose: We assessed the performance of metagenomic next-generation sequencing (mNGS) in the diagnosis of infectious encephalitis and meningitis.

Methods: This was a prospective multicenter study. Cerebrospinal fluid samples from patients with viral encephalitis and/or meningitis, tuberculous meningitis, bacterial meningitis, fungal meningitis, and non-central nervous system (CNS) infections were subjected to mNGS.

Results: In total, 213 patients with infectious and non-infectious CNS diseases were finally enrolled from November 2016 to May 2019; the mNGS-positive detection rate of definite CNS infections was 57.0%. At a species-specific read number (SSRN) ≥2, mNGS performance in the diagnosis of definite viral encephalitis and/or meningitis was optimal (area under the curve [AUC] = 0.659, 95% confidence interval [CI] = 0.566–0.751); the positivity rate was 42.6%. At a genus-specific read number ≥1, mNGS performance in the diagnosis of tuberculous meningitis (definite or probable) was optimal (AUC=0.619, 95% CI=0.516–0.721); the positivity rate was 27.3%. At SSRNs ≥5 or 10, the diagnostic performance was optimal for definite bacterial meningitis (AUC=0.846, 95% CI = 0.711–0.981); the sensitivity was 73.3%. The sensitivities of mNGS (at SSRN ≥2) in the diagnosis of cryptococcal meningitis and cerebral aspergillosis were 76.92 and 80%, respectively.

Conclusion: mNGS of cerebrospinal fluid effectively identifies pathogens causing infectious CNS diseases. mNGS should be used in conjunction with conventional microbiological testing.

Trial Registration: Chinese Clinical Trial Registry, ChiCTR1800020442.

Apparent performance of metagenomic next-generation sequencing in the diagnosis of cryptococcal meningitis: a descriptive study

INTRODUCTION

In recent years, metagenomic next-generation sequencing (mNGS) has become widely used in medical microbiology to detect pathogen infection.

AIM

We aimed to assess the diagnostic performance of mNGS of cerebrospinal fluid (CSF) for prediction of cryptococcal meningitis (CM).

METHODOLOGY

A comparative evaluation of mNGS (performed on CSF samples) and conventional methods, including India ink staining, culture for fungi and cryptococcal-antigen (CrAg) detection by enzyme immunoassay, was performed on 12 consecutive non-HIV-infected patients with chronic or subacute CM.

RESULTS

India ink staining and culture of the CSF were positive for Cryptococcus in 83.33 % (10/12) of the samples; 100 % (11/11) were positive via CrAg EIA. The mNGS results of the CSF identified DNA sequences corresponding to Cryptococcus in 75 % of samples (9/12). However, the DNA of both C. neoformans s.l. and C. gattii s.l. was detected concurrently in 33.33 % (4/12).

CONCLUSION

mNGS is helpful for identifying Cryptococcus species. The application of mNGS, together with India ink staining, culture methods, and CrAg, may significantly improve the diagnostic precision in CM, thereby informing choice of appropriate antifungal treatment courses.

Evaluation of Next-Generation Sequencing for the Diagnosis of Infections of the Central Nervous System Caused by the Neurotropic Herpes Viruses: A Pilot Study

Background: There are sparse and limited studies on small sample size reporting the application of next-generation sequencing (NGS) in the detection of central nervous system (CNS) viral infections. We assessed the diagnostic performance of NGS of cerebrospinal fluid (CSF) for predicting viral infections of the CNS caused by the neurotropic herpes viruses in a pilot population. Materials and Methods: We prospectively collected CSF samples from 24 patients with CNS viral infection from April 2017 to October 2018. Of the 24 patients, 19 patients were infected with herpes simplex virus 1 (HSV-1), 1 patient with HSV-2, and 4 patients with varicella-zoster virus (VZV). All CSF samples were screened for viral DNA using NGS technologies to detect viral CNS infections. Results: Of the 24 patients with confirmed viral CNS infection caused by the neurotropic herpes viruses, 10 (10/24, 41.67%) patients exhibited positive NGS results. With the help of NGS, HSV-1 DNA was detected in the CSF of 6 patients (6/19; 31.58%). HSV-2 DNA was detected in 1 patient (1/1; 100%) and VZV DNA was detected in 3 patients (3/4; 75%). The positive rate of virus detected by NGS decreased with time. The positive rates of NGS of CSF in the first, second, and third weeks were 54.5% (6/11), 44.4% (4/9), and 0% (0/4), respectively. Conclusions: NGS method is a promising pathogen detection tool for identifying viral CNS infections. It should be recommended to sequence viral DNA of CSF in the early stage of CNS viral infections.

The Role of miR-150 in Stress-Induced Anxiety-Like Behavior in Mice

Stress plays a crucial role in several psychiatric disorders, including anxiety. However, the underlying mechanisms remain poorly understood. Here, we used acute stress (AS) and chronic restraint stress (CRS) models to develop anxiety-like behavior and investigate the role of miR-150 in the hippocampi of mice. Corticosterone levels as well as glutamate receptors in the hippocampus were evaluated. We found that anxiety-like behavior was induced after either AS or CRS, as determined by the open-field test (OFT) and elevated plus-maze test (EPM). Increased corticosterone levels were observed in the blood of AS and CRS groups, while the expression of miR-150 mRNA in the hippocampus was significantly decreased. The expressions of GluN2A, GluR1, GluR2, and V-Glut2 in the hippocampus were decreased after either AS or CRS. Hippocampal GAD67 expression was increased by AS but not CRS, and GluN2B expression was decreased by CRS but not AS. Adult miR-150 knockout mice showed anxiety-like behavior, as assessed by the OFT and EPM. The expressions of GluN2A, GluN2B, GluR1, and GluR2 were also downregulated, but the expression of V-Glut2 was upregulated in the hippocampi of miR-150 knockout mice compared with wild-type mice. Interestingly, we found that the miR-150 knockout mice showed decreased dendrite lengths, dendrite branchings, and numbers of dendrite spines in the hippocampus compared with wild-type mice. These results suggest that miR-150 may influence the synaptic plasticity of the hippocampus and play a significant role in stress-induced anxiety-like behavior in adult mice.

Downregulation of the β1 adrenergic receptor in the myocardium results in insensitivity to metoprolol and reduces blood pressure in spontaneously hypertensive rats

The β1‑adrenergic receptor (AR) is the primary β‑AR subtype in the heart and is the target of metoprolol (Met), which is commonly used to treat angina and hypertension. Previous studies have revealed a positive correlation between the methylation levels of the adrenoreceptor β1 gene (Adrb1) promoter in the myocardium with the antihypertensive activity of Met in spontaneously hypertensive rats (SHR), which affects β1‑AR expression in H9C2 cells. The aim of the present study was to investigate the effects of myocardial β1‑AR downregulation using short‑hairpin RNA (shRNA) against Adrb1 on the antihypertensive activity of Met in SHR. Recombinant adeno‑associated virus type 9 (rAAV9) vectors carrying Adrb1 shRNA (rAAV9‑Adrb1) or a negative control sequence (rAAV9‑NC) were generated and used to infect rat hearts via the pericardial cavity. The results of reverse transcription‑quantitative polymerase chain reaction, immunohistochemistry and western blotting analyses demonstrated that cardiac β1‑AR expression in the rAAV9‑Adrb1 group was significantly downregulated when compared with the rAAV9‑NC group (P<0.001, P<0.001 and P=0.032, respectively). In addition, a greater reduction in systolic blood pressure (SBP) was observed in the rAAV9‑NC group compared with the rAAV9‑Adrb1 group following Met treatment (P=0.035). Furthermore, downregulation of myocardial β1‑AR was associated with a significant decrease in SBP (P<0.001). In conclusion, these data suggest that suppression of β1‑AR expression in the myocardium reduces SBP and sensitivity to Met in SHR.

[Preparation of SUN5-specific polyclonal antibody for detection of SUN5 expression in human germ cells]

OBJECTIVE

To prepare a specific polyclonal antibody against full-length SUN5 for detecting the expression of SUN5 in human germ cells.

METHODS

Bioinformatic methods were used to compare the full-length SUN5 and its variant SUN5β, and a short peptide was designed based on the differential region to prepare SUN5 antibody. The prepared antibody was used to detect the expression of SUN5 in Ntera-2 cells and in human germ cells by Western blotting and immunofluorescence assay.

RESULTS

The short peptide was correctly synthesized and SUN5 antibody was obtained and purified. Western blotting showed that the prepared antibody was capable of recognizing full-length SUN5 in Ntera-2 cells, and SUN5 expression was localized on the nuclear membrane and in the cytoplasm as shown by immunofluorescence assay. Using this antibody, we detected SUN5 expression in the spermatocytes, round spermatids and sperms in human germ cells.

CONCLUSION

We successfully prepared SUN5-specific antibody. SUN5 is expressed in the spermatocytes, round spermatids and sperms in human germ cells, suggesting its important role in spermatogenesis.

Autoimmune encephalitis mimicking sporadic Creutzfeldt-Jakob disease: A retrospective study

Autoimmune encephalitis associated with anti-voltage-gated potassium channel antibodies are most likely to be misdiagnosed as sporadic Creutzfeldt-Jakob disease (sCJD). Our goal was to delineate patients who were initially suspected to have CJD but were later found to have AE. We performed a retrospective clinical review of cases of individuals and made a comparison between groups of patients diagnosed with sCJD and AE. Patients who had rapidly progressing dementia and focal neurological impairment, such as aphasia, gait disturbance, visual disturbance, and depression, at onset were diagnosed with sCJD, whereas epilepsy, hyponatremia and dysautonomia were strong hints for AE. Fluoroscope-positron emission tomography (PET) of patients with AE revealed variable metabolism and normative and long-term immunosuppression were less likely to relapse.

Voriconazole: a novel treatment option for cryptococcal meningitis

BACKGROUND

Cryptococcal meningitis (CM) is a relatively common opportunistic infection in patients with human immunodeficiency virus (HIV) infection and can also occur in patients with no underlying disease. The aim of this study was to evaluate the clinical manifestations, laboratory findings, diagnosis and misdiagnosis, treatment, and prognosis of CM at a tertiary care hospital.

METHODS

We performed a retrospective study of 55 patients at a tertiary care hospital from January 1, 1992 to December 31, 2013. All the patients had a definite diagnosis based on etiology.

RESULTS

All 55 patients had a positive cerebrospinal fluid (CSF) India ink staining result. The predominant change observed on magnetic resonance imaging (MRI) was leptomeningeal liner enhancement, which is also called 'lumbriciform-enhancing.' Only 15 patients were first diagnosed with CM, indicating a misdiagnosis rate of 72.7%. At the follow-up end point, 8 patients were cured, 33 had improved, and 14 had died. The overall response rate was 74.5%. The voriconazole group had a response rate of 100%, which was significantly higher than the other two groups.

CONCLUSIONS

Most CM patients in China were previously healthy without any potential risk factors. CM was easily misdiagnosed due to the lack of specificity of early clinical symptoms. Repeated CSF India ink staining should be performed to identify the pathogen. Voriconazole could be administered to the patients with CM, especially to patients who had a treatment failure with amphotericin B alone or accompanied by fluconazole.

Development of anxiety-like behavior via hippocampal IGF-2 signaling in the offspring of parental morphine exposure: effect of enriched environment

Opioid addiction is a major social, economic, and medical problem worldwide. Long-term adverse consequences of chronic opiate exposure not only involve the individuals themselves but also their offspring. Adolescent maternal morphine exposure results in behavior and morphologic changes in the brain of their adult offspring. However, few studies investigate the effect of adult opiate exposure on their offspring. Furthermore, the underlying molecular signals regulating the intergenerational effects of morphine exposure are still elusive. We report here that morphine exposure of adult male and female rats resulted in anxiety-like behavior and dendritic retraction in the dentate gyrus (DG) region of the hippocampus in their adult offspring. The behavior and morphologic changes were concomitant with the downregulation of insulin-like growth factor (IGF)-2 signaling in the granular zone of DG. Overexpression of hippocampal IGF-2 by bilateral intra-DG injection of lentivirus encoding the IGF-2 gene prevented anxiety-like behaviors in the offspring. Furthermore, exposure to an enriched environment during adolescence corrected the reduction of hippocampal IGF-2 expression, normalized anxiety-like behavior and reversed dendritic retraction in the adult offspring. Thus, parental morphine exposure can lead to the downregulation of hippocampal IGF-2, which contributed to the anxiety and hippocampal dendritic retraction in their offspring. An adolescent-enriched environment experience prevented the behavior and morphologic changes in their offspring through hippocampal IGF-2 signaling. IGF-2 and an enriched environment may be a potential intervention to prevention of anxiety and brain atrophy in the offspring of parental opioid exposure.

SPAG4L, a novel nuclear envelope protein involved in the meiotic stage of spermatogenesis

SUN domain-containing proteins belong to a novel protein family. To date, several members--SUN1, SUN2, SUN3, and SPAG4--have been identified as nuclear envelope (NE) proteins. In this study, we sought to characterize and define the potential function of SPAG4L, a newly identified SUN protein. Using bioinformatic analysis, we found that SPAG4L contained a conserved SUN domain in the C-terminal. Subcellular localization analysis indicated that the expression of green fluorescent protein-labeled full-length SPAG4L was localized to the NE and the endoplasmic reticulum (ER). Deletion analysis revealed that the transmembrane region and the coiled-coil domain, but not the SUN domain, were required for localization of SPAG4L to the NE and ER. Subsequently, we confirmed that the human testes expressed endogenous SPAG4L as a 43-kDa protein. Further studies revealed that mouse Spag4L colocalized with the NE marker Lamin B1 and the ER marker PDI in isolated mouse spermatocytes. In addition, the expression of Spag4L was observed in meiosis I and II stages, suggesting that Spag4L may be involved in NE reconstitution and nuclear migration occurring during the process of spermatocyte division. Together, the findings indicate that SPAG4L, a new NE protein, may play an important role in the meiotic stage of spermatogenesis.

[Construction of SOD1 eukaryotic expression vector and its expression]

AIM

to construction of eukaryotic expression vector of the human SOD1 (Cu/Zn superoxide dismutase, SOD1) and expression in HeLa cells.

METHODS

the open reading frame (ORF) of SOD1 was amplified from human peripheral blood by RT-PCR. TA cloning strategy was used to insert the target fragments into pUCm-T vector. The recombinant plasmid was identified and noted as pUCm-T-SOD1. Then, SOD1 was subcloned into pTracer-CMV/Bsd, a eukaryotic expression vector. The plasmid of pTracer-CMV/Bsd-SOD1 was sequenced and was introduced into HeLa cells by Lipofectamine(TM); 2000. The expression of green fluorescence protein (GFP) was observed by the fluorescence microscope. The expression of SOD1 was detected by RT-PCR and Western blot after screening by blasticidin for 4 weeks.

RESULTS

the eukaryotic expression plasmid pTracer-CMV/Bsd-SOD1 was successfully constructed. The GFP was observed in transfected cells by the fluorescence microscope. The expression of SOD1 was detected in transfected cells by RT-PCR and Western blot.

CONCLUSION

the recombinant eukaryotic expression vector of pTracer-CMV/Bsd-SOD1 has been constructed successfully which could express GFP and SOD1, respectively, providing a tool for further gene therapy study.

Investigation of porcine endogenous retrovirus in the conservation population of Ningxiang pig

Porcine endogenous retrovirus (PERV) varies between pig breeds. Screening and analysis of PERV in putative pig breeds may provide basic parameters to evaluate the biological safety of xenotransplantation from pigs to humans. In this study, PERV was investigated among the conservation population of the Ningxiang pig. The result revealed that the genotype of PERV distribution was subtype A, 100%; subtype B, 100%; and subtype C, 100%. The env sequences of PERV-A and -B showed 11 clones detected by KpnI and MboI digestion, indicating that there existed multiple variants of PERV-A and -B in the Ningxiang pig. Reverse transcriptase polymerase chain reaction results showed that PERV had transcriptional activity in these individuals. In addition, PERV A/C recombinant was detected in most individuals of Ningxiang pig. Because PERV A/C recombinants increase the potential infectious risk, the breed may not be a proper donor for xenotransplantation.

[Expression of PDCD5 in multiple myeloma and its relation with BCL-2]

OBJECTIVE

To determine the expression of apoptosis related gene PDCD5 in multiple myeloma (MM), and to analyze the relation between PDCD5 and BCL-2.

METHODS

The expressions of PDCD5 and BCL-2 protein and mRNA were determined by immunohistochemical staining method, flow cytometry (FCM) and reverse transcription polymerase chain reaction (RT-PCR) method in bone marrow mononuclear cells. We also analyzed the relation between PDCD5 and BCL-2.

RESULTS

Immunohistochemical staining showed that PDCD5 protein positive cell percentage, staining intensity index (SII) of PDCD5 protein, BCL-2 protein positive cell percentage, and SII of BCL-2 protein were (34.75 +/- 6.49)%, (281.16 +/- 75.33), (29.97 +/- 5.57)%, and (224.94 +/- 57.72) in the MM group and (52.98 +/- 5.84)%, (462.84 +/- 39.77), (5.56 +/- 1.95)%, and (27.84 +/- 9.75) in the control group (all P < 0.05). Results of FCM showed that PDCD5 protein positive percentage and mean fluorescence intensity of PDCD5 were (78.11 +/- 21.63)% and (61.73 +/- 11.04) in the MM group and (89.46 +/- 9.98)% and (353.04 +/- 123.26) in the control group (all P < 0.05). RT-PCR showed that relative expression of PDCD5 and BCL-2 mRNA were (0.33 +/ -0.07) and (0.33 +/- 0.08) in the MM group and (0.53 +/- 0.05) and (0.12 +/- 0.02) in the control group (all P < 0.05). The positive cell percentage of PDCD5 and BCL-2 protein was negative correlation (r = -0.86, P < 0.05); the expression of PDCD5 and BCL-2 mRNA was the same status (r = -0.90, P < 0.05).

CONCLUSION

The expressions of PDCD5 protein and mRNA in MM patients are down-regulated, but the expressions of BCL-2 protein and mRNA are up-regulated. The mRNA and protein expression of PDCD5 and BCL-2 has negative correlation.

[Cloning and bioinformatics analysis of SLA-DR genes in Hunan Shaziling pigs]

In order to clone class II DRA and DRB genes of swine leukocyte antigen (SLA) in Hunan Shaziling pigs, to analyze their characteristics and polymorphism and to provide immunological basic parameters for xenotransplantation from pigs to humans. SLA-DRA and SLA-DRB genes in two Shaziling pigs with the absence of porcine endogenous retrovirus (PERV) env-c were amplified by RT-PCR, cloned into PUCm-T vectors, sequenced and analyzed through BLAST in NCBI and related software in ExPASY. The obtained SLA-DRA and SLA-DRB genes of Shaziling pigs were 1,177 and 909 nucleotides in length with their accession numbers in Genbank as EF143987 and EF143988. Bioinformatics analyses have shown that they both contain opening reading frame (ORF) and encode 252 and 266 amino acids respectively. Comparing the ORF and protein sequences of the Shaziling SLA-DRA and SLA-DRB genes with their counterpart sequences of human, the homologies of nucleotide sequences were 83% and 83%, and the homologies of amino acid sequences 83 % and 79% respectively. Further comparison with SLA sequences published in GenBank indicated that SLA-DRB gene found in Shaziling pigs has polymorphism while the homology of SLA-DRA gene is up to 100 % .

[3 polymorphisms of gene GP IIb and the function of GP IIb T13959 G in the platelet transfusion refractoriness]

OBJECTIVE

To investigate the relationship among 3 polymorphisms of GP IIb and the function of GP IIb T13959 G in the platelet transfusion refractoriness(PTR).

METHODS

The 26th exon, the 30th exon and the 21st intron of gene GP IIb in 110 individuals were amplified by polymerase chain reaction (PCR), and the PCR products were analyzed with single-strand conformation polymorphism(SSCP) and sequenced to investigate whether there was linkage among the polymorphisms of the gene. Human platelet antigen-3 (HPA-3) gene frequency was detected by Fok I enzyme in 147 patients with hematologic diseases, and was compared with that in 110 normal individuals. Forty-four patients who received apheresis platelet transfusion repeatedly were randomly divided into the HPA-3 homotype group and the control group. The antibodies of the platelet were detected after 3 times of platelet transfusion.

RESULTS

There were polymorphisms of gene GP IIb in the 26th, 30th exon and the 21st intron, and the mutations were: T changed into G in 13,959 th of the 26th exon; C changed into T in 16,997 th of the 30th exon; the 9 bps deletion occurred in 11,996-12,004 th of the 21st intron. The 3 polymorphisms had synchronization in the individuals. The results of Fok I enzyme indicated that the frequency of HPA-3a was 83.6% (92/110)and 81.9%(119/147), and that of HPA-3b was 16.4%(18/110) and 19.1%(28/147) in the normal individuals and the patients respectively. There was no significant difference between the patients and normal individuals (P>0.05). After the platelet transfusion, the antibodies of all the cases of the homotype platelet transfusion were negative, but the antibodies in 2 cases of the control group were positive, and there was antibody to HPA-3a in one of the antibodies positive cases.

CONCLUSION

(1)There is close linkage among the polymorphisms of gene GP IIb, which is T->G in 13 959 th of the 26th exon, C->T in 16,997 th of the 30th exon, and the 9 bps deletion in 11,996-12,004 th in the 21st intron. (2)The gene frequency of HPA-3a/3b is similar in the normal individuals and patients with hematologic diseases. (3) HPA-3 system may be one of the reasons for PTR in Chinese.

[Expression of a novel spermatogenesis gene SRG4 in postpartum normal and cryptorchid mouse testis]

To understand the function of SRG4, a novel spermatogenesis gene, we studied its expression pattern during normal mouse development and in experimental cryptorchidism. Testis tissues were collected from 1-, 3-, and 12-week-old normal mice and immunohistochemistry was used to detect the expression of SRG4. We performed surgery on mice to cre- ate unilateral cryptorchidism and monitored SRG4 mRNA levels by semi-quantitative RT-PCR in the cryptorchid testis from day 0-18. At post-operative day 18, the cryptorchid testis and the contralateral control testis were harvested and assayed for SRG4 expression by in situ hybridization. Immunohistochemistry results showed that SRG4 protein was hardly detected in 1-week-old mouse testis, but the expression was present in 3-week-old mouse and abundant in 12-week-old mouse testis. SRG4 immunostaining was mainly localized to the cytoplasm and membrane of spermatocytes and round spermatids. Moreover, semi-quantitative RT-PCR result showed the expression of SRG4 mRNA did not decrease until 9 d after cryptorchid surgery, and continued to decline thereafter. In situ hybridization revealed that in contrast to the abundant SRG4 expression in the control side, few remaining germ cells in the crytorchid testis were positive for SRG4 at d 18 after surgery. The results indicated that the expression of SRG4 was regulated by development, and SRG4 was mainly expressed in the cytoplasm of spermatocytes and round spermatids. However, in cryptorchid testis, in which most germ cells undergo apoptosis, only a few of SRG4 is observed, suggesting that SRG4 may be as a specific marker to evaluate the process of spermatogenesis.

[Construction and expression of fusion gene eukaryotic expression plasmid of pEGFP-C(3)-insig2 and its influence to downstream genes]

AIM

To construct the eukaryotic expression plasmid of insig2 gene and detect the expression of downstream gene adiponectin and adipocyte fatty acid-binding protein 2 (AP2) after the transfection of 3T3-L1 cells.

METHODS

Insig2 gene of the mouse was amplified by RT-PCR and then cloned into the eukaryon expression vector pEGFP-C(3), After confirmed by double restriction enzyme digestion analysis and DNA sequencing, pEGFP-C(3)-insig2 was transfected into 3T3-L1 cells by lipofectamine 2000. The expression of insig2 and downstream gene in the 3T3-L1 cells were detected by RT-PCR and fluorescence microscope.

RESULTS

The eukaryotic expression plasmid of pEGFP-C(3)-insig2 was constructed. The expression of fusion protein in the endochylema was confirmed. The transcription of adiponectin mRNA and AP2 mRNA was down-regulated after transfection for 24 h and 72 h.

CONCLUSION

The eukaryotic expression plasmid of pEGFP-C(3)-insig2 is successfully constructed. The transfected insig2 may have an effect on fat metabolism of 3T3-L1 cells.

[Porcine endogenous retrovirus in Daweizi pigs in Hunan]

OBJECTIVE

To detect porcine endogenous retrovirus (PERV) in Daweizi pigs and to provide basic parameters of evaluating the biological safety for xenotransplantation from pigs to humans.

METHODS

Ear tissues from 42 individuals were randomly collected from a Daweizi pig population. PCR and RT-PCR were performed to detect PERV proviral DNA and mRNA respectively. Finally, env-A, env-B, and env-C were amplified, sequenced, and analyzed using the BLAST software in National Center for Biotechnology Information.

RESULTS

PERV proviral DNA and mRNA could be detected in the 42 individuals by PCR and RT-PCR, respectively. env-A, env-B and env-C were detected in all the individuals. Compared with other pig species (AY288779, DQ011794 and AY534304), there was 1 and 8 bp differences in the sequences of env-A and env-C, while no difference in env-B.

CONCLUSION

PERV exists and has transcriptive activity in Daweizi pigs. The predominate subtype is PERV-ABC. Env genes are firstly cloned and sequenced in Daweizi pigs and there are polymorphism in the breed. As to the biological safety, the breed was not suitable as a donor in xenotransplantation.

[Research of porcine endogenous retrovirus in Shaziling pigs]

To provide basic parameters of evaluating the biological safety of xenotransplantation from pig to human, ear tissues from 31 individuals were randomly collected from a Shazi Ling pig population. PCR and RT-PCR were performed to detect porcine endogenous retrovirus (PERV) proviral DNA and mRNA respectively. The sensitivity of the PCR was evaluated using a positive control. To study tissue distribution, RT-PCR of pol, gag and env was performed in the kidney, heart, liver, lung and spleen of 3 individuals. Finally, env-A, env-B and env-C were amplified, sequenced and analyzed using the BLAST software in NCBI (National Center for Biotechnology Information). The results showed PERV proviral DNA and mRNA could be detected in all 31 individuals by PCR and RT-PCR, respectively. env-A, env-B and env-C were only detected in 2 individuals, while in the other 29 individuals, only env-A and env-B but not env-C was detected. The quantity of DNA in PCR amplification of PERV genes should be more than 15 ng. RT-PCR results showed gag, pol, env-A and env-B were expressed in the kidney, heart, liver, lung and spleen of all 3 individuals, but env-C was not. Sequencing of env genes in Shazi Ling pigs revealed that while there was no difference in env-A sequence when compared to other herd in GenBank, there were 2 and 10 bp differences in the sequences of env-B and env-C respectively, suggesting that env gene is polymorphic in different pig strains. PERV exists in the Shazi Ling pig population and the predominant subtype is PERV-A, B. The distribution of PERV displays no significant tissue specificity and env-C is absent in 93.5% (29/31) of the individuals. The results indicate that Shazi Ling pig may have great potential value as a candidate in xenotransplantation.

Molecular cloning of a novel mouse testis-specific spermatogenic cell apoptosis inhibitor gene mTSARG7 as a candidate oncogene

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.

[Cloning of cDNA of SRG4, a mouse spermatogenesis related gene and expression in mouse different developing stages]

Spermatogenesis required lots of genes taking part in this process. In prevision studies, Odf1, Odf2, Sak57, Spag4, Spag5 were identified in mouse and rat sperm tail developing. Two ESTs, BG101130 and BG100990, which coded amino acid sequences with high homology to rat Spag4, were found from mouse spermatocytes. By electrical hybridization, a 1 155 bp sequence was obtained and named as SRG4 (Spermatogenesis Related Gene 4) (GenBank accession number: AY307077), which included the full-length sequence of mouse testis hypothetical gene AK006225. The opening reading frame of SRG4 was 87 approximately 1 133 bp, and was proved by RT-PCR in mouse testis. The information analysis showed SRG4 gene was located in 2H1-H2, and the putative protein was 348-amino acid with a coiled-coil region, suggesting SRG4 might function as a transmembrane protein. The homologies of amino acid sequences were 74% between TSARG4 and SRG4 gene and 45% between SRG4 and rat Spag4 gene, respectively. RT-PCR and Northern blot results showed SRG4 gene expressed specifically in mouse testis. Changes of SRG4 expression in mouse different developing stages were observed. The results showed SRG4 gene expressed slightly in two weeks postpartum, and expressed abundantly from three weeks, and reached the top at 4 -5 weeks. This indicted SRG4 gene may play an important role in mouse spermatogenesis.

Cloning of a full-length cDNA of human testis-specific spermatogenic cell apoptosis inhibitor TSARG2 as a candidate oncogene

A novel human gene full-length cDNA sequence-TSARG2 was identified from a human testis cDNA library using the SRG2 gene (GenBank Accession No. ), which was significantly up-regulated in cryptorchidism, as an electronic probe. TSARG2 was 1223 bp in length. The putative protein encoded by this gene was 305 amino acids with a theoretical molecular weight of 34,751 and isoelectric point of 9.85. The sequence shared no significant homology with any known protein in databases except SRG2. Northern blot analysis revealed that 1.7 kb TSARG2 transcript was detected selectively in human testis. Furthermore, results of in situ hybridization assay confirmed that TSARG2 was expressed in seminiferous tubules, more precisely in spermatogonia and spermatocyte. No mutation was found by PCR-SSCP in 122 cases of azoospermia, severe oligzoospermia, and cryptorchidism. The green fluorescence produced by pEGFP-C1/TSARG2 was detected on the nucleus of COS7 cells after 24h post-transfection. The pcDNA3.1(-)/TSARG2 plasmid was constructed and introduced into MCF7 cells by liposome transfection. TSARG2 can accelerate MCF7 cells to traverse the S-phase and enter the G2-phase compared with the control without transfection of TSARG2, which suggested that this gene plays an important role in the development of cryptorchid testis and is a testis-specific apoptosis candidate oncogene.

[Molecular cloning and expression analysis of a novel human testis-specific gene]

Digital Differential Display (DDD) of the National Center for Biotechnology Information (NCBI) is a quantitative method that enables the user to determine the fold differences between the libraries being compaired, using a statistical method to quantitate the transcript levels. In this study, DDD program was performed between nine testis libraries ('tester') and seventy-six libraries derived from other tissues ('driver'). We identified a new contig of expression sequence tags (ESTs) HS. 129794 which were from testis libraries. To validate the use of bioinformatics approaches in gene discovery, the ESTs HS. 129794, which was predicted to be testis -specific, was chosen for further study. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis of mRNA from different normal tissues indicated that HS. 129794 was specifically expressed in human testis. By querying EST and Unigene datagases, a full-length cDNA sequence of novel gene in human were identified, it was 2 430 bp in length, located in chromosome 3p21.1. The sequence of the open reading frame was 676 approximately 1 248 bp, as was confirmed by RT-PCR and sequencing in human testis. The cDNA encodes a novel protein of 190 amino acids with a theoretical molecular weight of 20 417.8 and isoelectric point of 5.23. The sequence shares no significant homology with any known protein in databases. Semi-quantitative RT-PCR analysis of multiple tissues further showed that the novel gene is expressed significantly in different stage of human testis and sperm. We hypothensize that its functions as a testis-specific and spermatogenesis related gene that plays some roles in spermatogenesis, and named it SRG5 (Testis Spermatogenesis Related Gene 5, SRG5) (GeneBank accession number: AY221117). Identification of SRG5 using DDD approaches validates gene discovery using computational approaches.

Identification of a novel gene SRG4 expressed at specific stages of mouse spermatogenesis

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.

Molecular cloning of TSARG6 gene related to apoptosis in human spermatogenic cells

Beginning from a mouse EST (GenBank accession No. BE644537) which was significantly up-regulated in cryptorchidism and represented a novel gene, we cloned a new gene (GenBank accession No. AY138810) which is related to apoptosis in human spermatogenic cells by means of GeneScan program and PCR technology. The gene whose full cDNA length is 1875 bp containing 8 exons and 7 introns is located in human chromosome 11q13.3. Its protein containing 316 amino acid residues is a new member of HSP40 protein family because the sequence contains the highly conserved J domain which is present in all DnaJ-like proteins and is considered to have a critical role in DnaJ-DnaK protein-protein interactions. TSARG6 protein displays a 45% identity in a 348-amino acid overlap with DJB5_HUMAN protein. The result of RT-PCR and Northern blot analysis showed that TSARG6 is specifically expressed in adult testis and the transcript is 1.8 kb. Based upon all these observations, it is considered that we cloned a new gene which probably inhibited human testis spermatogenesis apoptosis.

[Molecular cloning of mTSARG3 gene related to apoptosis in mouse spermatogenic cells]

Beginning from a mouse EST (GenBank Accession No: BE644537) which was significantly changed in cryptorchidism and represented a novel gene, GeneScan program was performed and a predicted mouse novel gene full-length cDNA sequence containing the BE644537 sequence was attained. Gene-specific primers were designed for PCR in mouse testis cDNA library. The sequencing result of the PCR product showed that we obtain a new gene mTSARG3 (GenBank Accession No: AF419292) whose full cDNA length is 1328 bp containing 8 exons and 7 introns. The predicted open reading frame encodes a protein of 316 amino acid residues. The protein encoded by the new gene is a new member of HSP40 protein family because the sequence contains the highly conserved J domain which is present in all DnaJ-like proteins and is considered to have a critical role in DnaJ-DnaK protein-protein interactions. mTSARG3 protein displays a 46% identity in a 336-amino-acid overlap with DJB4-MOUSE protein. The result of RT-PCR analysis and Northern blot showed that mTSARG3 is specifically expressed in mouse testis. Southern blot showed that there were no loss and rearrangement in cryptorchid. Based upon all these observations, it is considered that the function of the new gene is related to inhibit mouse testis spermatogenesis apoptosis.

[Molecular cloning and expression in cryptorchid testis of SRG2 from a mouse testis spermatocyte apoptosis-related gene]

It was observed that the spermatogenic cells apoptosis dramatically increased in infertile man. Cloning of novel spermatogenic cell-specific gene related to apoptosis is of momentous physiological and pathological significance to illustrate the apoptosis mechanism and the biology process of spermatogenic cells. A novel mouse gene full-length cDNA sequence-SRG2 was identified (GenBank accession number AF395083), which was significantly changed in cryptorchidism, from a mouse testis cDNA library using a cDNA fragment (GenBank accession number BE644542) as an electronic probe. SRG2 was 1,088 bp in length. The putative protein encoded by this gene was 295 amino acids with a theoretical molecular weight of 33,579 kDa and isoelectric point of 9.64. The sequence shared no significant homology with any known protein in databases except TSARG2, with which its homology was 78%. RT-PCR showed that SRG2 was expressed significantly in testis. Using molecular beacon probe to examine the mRNA expression level of SRG2 gene in cryptorchid testis of various stages, we found that the gene was up-regulated distinctly. Therefore, we conclude that this gene plays an important role in cryptorchid testis.

Expression research for human DDX36 and mouse Ddx36 gene in the adult testis

Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for structural and functional genomic research. With the strategy of homologue molecular cloning using the sequence of the maleless gene (mle) of Drosophila, the novel homologous human and mouse genes with longer DNA/RNA helicase box (DEAD/DEAH box), named, DDX36 and Ddx36 genes, respectively, were cloned as new members of the DEAD/H box superfamily. In order to further investigate the relationship between those two genes of DDX36 and Ddx36 and the role of spermatogenesis, the expression analysis of them have been performed by the techniques of Northern blotting, RT-PCR and tissue in situ hybridization. The result indicated that the DDX36 and Ddx36 gene has highly expressed in the adult testis. It was primarily suggested that DDX36 and Ddx36 gene may be related with spermatogenesis.

[Cloning of cDNA of TSARG4, a human spermatogenesis related gene]

To understand molecular mechanism of spermatogenesis, two ESTs BG720564 and AI700454, were found from SPAG4 (sperm antigen 4), a gene related to dense fiber protein of outer membrane of the human sperm and mouse spermatocytes gene AK006225. The gap was filled by polymerase chain reaction, and a 1252 bp fragment was obtained. This 1252 bp fragment was named TSARG4 (testis and spermatogenesis related gene 4 (GenBank accession number AF401350). Its opening reading frame was 94-1233 bp, as was proved by RT-PCR in human testis. TSARG4 gene was located in 20q11.2, and the putative protein was 379 amino acid with a theoretical molecular weight of 43 081 and isoelectric point of 8.61. The homologies of amino acid sequences were 74% between TSARG4 and AK006225 gene and 45% between TSARG4 and SPAG4 gene, respectively. The human TSARG4 mRNA is expressed in a wide range of adult tissues, including testis, whereas the homologous mouse spermatocytes gene AK006225 is expressed specifically in the testis.

[Molecular cloning for testis spermatogenesis cell apoptosis related gene TSARG1 and Mtsarg1 and expression analysis for Mtsarg1 gene]

Spermatogenesis cell apoptosis is a very complex process, which needs many molecules to take part in the programmable death of cells in testis. At present, research of apoptosis for spermatogenesis cell is at the primary step. It is very important to clone spermatogenesis cell apoptosis related genes and spermatogenesis genes in testis. Applying the bioinformatics and experiment technique, we have cloned human and mouse novel gene cDNA sequences--human testis and spermatogenesis cell apoptosis related gene 1 (TSARG1) and mouse testis and spermatogenesis cell apoptosis related gene 1(Mtsarg1) from human and mouse testis cDNA library respectively, using a cDNA fragment (GenBank accession number: BE644538) as an electronic probe, which was significantly changed in expression in cryptorchidism. The GeneBank accession numbers of Mtsarg1 and TSARG1 are AF399971 and AY032925 (NM_139073), respectively. The Mtsarg1 has a 55% identity and 61% similarity with TSARG1 at the amino acid level, which did not share significant homology with any other known protein in databases. The full-length cDNA of TSARG1 gene is 973 bp, including 549 bp open reading frame(ORF) and coding 183 amino acids, whereas the full-length cDNA of Mtsarg1 gene is 1103 bp, including 576 bp ORF and coding 192 amino acids. The predicted molecule weight of TSARG1 is 19948.61 Dolton, and the deduced iso-electric point is 10.24, whereas the Mtsarg1 is 20875.93 and is 9.83, being alkaline proteins. RT-PCR analysis showed that Mtsarg1 was expressed significantly in testis and faintly in epididymis in the ten tissues of testis, ovary, spleen, kidney, lung, heart, brain, epididymis, liver and skeletal muscle in mouse, while it wasn't expressed in the other eight tissues. Therefore, our results suggested that Mtsarg1 and TSARG1 would be pay potential roles in spermatogenesis cell apoptosis or spermatogenesis.

[Molecular cloning of SRG2, a mouse testis spermatocyte apoptosis-related gene]

A novel mouse gene full-length cDNA sequence-SRG2 were identified (GenBank accession number AF395083), which was significantly changed in cryptorchidism, from a mouse testis cDNA library using a cDNA fragment (GenBank accession number BE644542) as an electronic probe. SRG2 was 1058 bp in length. The putative protein encoded by this gene was 295 amino acids with a theoretical molecular weight of 33 579 and isoelectric point of 9.64. The sequence shared no significant homology with any known protein in databases except TSARG2, with which its homology was 78%. RT-PCR showed that SRG2 was expressed significantly in testis.

[Rapid identification of human testis spermatocyte apoptosis-related gene, TSARG2, by nested PCR and draft human genome searching]

Cloning apoptosis-related novel genes is a key to further understanding of apoptosis mechanism and the biology process of germ cells, and is of momentous significance on clarifying physiological and pathological process of spermatogenesis. To rapidly attain human novel gene full-length cDNA sequence, the gene-specific primers and the vector-specific primers were designed for nested PCR, and draft human genome searching was performed to rapidly identify the TSARG2 (GenBank accession number AY040204) 5' end from a human testis cDNA library, by using a cDNA fragment (GenBank accession number BE644542) as an electronic probe, which was significantly changed in cryptorchidism and represented a novel gene. Furthermore, a mouse homologue of this gene was identified (GenBank accession number AF395083) by lab on-line. TSARG2 with a 1 233 bp length was composed of 6 exons and spanned about 115 kb of genomic DNA, The putative protein encoded by this gene was 305 amino acid with a theoretical molecular weight of 34 751 dalton and did not share significant homology with any known protein in databases. TSARG2 was expressed in many tissues and mapped to chromosome 4q33-34.1 by database analyses. Therefore, we propose that nested-PCR and draft human genome searching are rapid, sensitive, accurate and efficient method for isolating gene 5' end, even full-length gene from cDNA library.