Identification and Characteristics of a Novel E1 Like Gene nUBE1l in Human test

The selective degradation of many short一lived or abnormal Proteins in eukaryotic cells 15 carried out by the ubiquitin system.In this Pathway,Proteins are targeted for degradation by covalent ligation to ubiquitin,a highly conserved 76一resid…     

ESX1L, a novel X chromosome-linked human homeobox gene expressed in the placenta and testis

A novel human homeobox gene related to the mouse Esx1 homeobox gene, which we have designated ESXR1, has been identified. ESXR1 and Esx1 share 65% identity within their homeodomains and have glutamic acid-rich and proline-rich N- and C-terminal regions, respectively. Unlike Esx1, ESXR1 contains 12 repeats of a unique nine amino acid motif, PPMAP(V/L)PPG, located C-terminal to the homeodomain. The general exon-intron structures of ESXR1 and Esx1 appear to be conserved. ESXR1 has been localized to human Xq22.1-q22.3, the same region of synteny shared by the map position of Esx1. ESXR1 expression appears to be restricted to the placenta and testis, the tissues in which Esx1 is also expressed. These data suggest that ESXR1 may be the orthologue of Esx1. The findings that there are similarities between ESXR1 and Esx1, yet differences between their encoded products, are consistent with the idea that placental genes evolve rapidly between mammalian species.     

Cloning of a novel human NHEDC1 (Na+/H+ exchanger like domain containing 1) gene expressed specifically in testis

The Na⁺/H⁺ exchangers (NHEs) catalyze the transport of Na⁺ in exchange for H⁺ across membranes in organisms and are required for numerous physiological processes. Here we report the cloning and characterization of a novel human NHEDC1 (Na⁺/H⁺ exchanger like domain containing 1) gene, which was mapped to human chromosome 4p24. This cDNA is 1859 bp in length, encoding a putative protein of 515 amino acids. The NHEDC1 proteins are highly conserved in mammals including human, mouse, rat, and Macaca fascicularis. One remarkable characteristic of human NHEDC1 gene is that it is exclusively expressed in the testis by RT-PCR analysis. Western blot analysis showed that the molecular weight of NHEDC1 is about 56 KDa. Guangming Ye and Cong Chen contributed equally to this work.     

Identification and characterization of YME1L1, a novel paraplegin-related gene

A gene responsible for an autosomal recessive form of hereditary spastic paraplegia (SPG7) was recently identified. This gene encodes paraplegin, a mitochondrial protein highly homologous to the yeast mitochondrial AAA proteases Afg3p, Rca1p, and Yme1p, which have both proteolytic and chaperone-like activities at the inner mitochondrial membrane. By screening the expressed sequence tag database, we identified and characterized a novel human gene, YME1L1 (YME1L1-like1, HGMW-approved symbol). This gene encodes a predicted protein of 716 amino acids highly similar to all mitochondrial AAA proteases and in particular to yeast Yme1p. Expression and immunofluorescence studies revealed that YME1L1 and paraplegin share a similar expression pattern and the same subcellular localization in the mitochondrial compartment. YME1L1 may represent a candidate gene for other forms of hereditary spastic paraplegia and possibly for other neurodegenerative disorders.     

Identification and characterization of a novel cancer/testis antigen gene CAGE

We applied serological analysis of cDNA expression library technique to identify cancer-associated genes. We screened cDNA expression libraries of human testis and gastric cancer cell lines with sera of patients with gastric cancers. We identified a gene whose expression is testis-specific among normal tissues. We cloned and characterized this novel gene. It contains D-E-A-D box domain and encodes a putative protein of 630 amino acids with possible helicase activity. It showed wide expression in various cancer tissues and cancer cell lines. The corresponding gene was named cancer-associated gene (CAGE). PCR of human x hamster Radiation Hybrids showed localization of CAGE on the human chromosome Xp22. Transient transfection of CAGE showed predominantly nuclear localization. Both Western blot and plaque assay indicated seroreactivity of CAGE protein. We found that demethylation played a role in the activation of CAGE in some cancer cell lines that do not express it. Cell synchronization experiments showed that the expression of CAGE was related with cell cycle. This suggests that CAGE might play a role in cellular proliferation. Because CAGE is expressed in a variety of cancers but not in normal tissues except testis, this gene can be a target of antitumor immunotherapy.     

Identification of novel mutations in L1CAM gene by a DHPLC-based assay

X-linked hydrocephalus, MASA syndrome, X-linked complicated Spastic Paraplegia Type I, and X-linked partial agenesis of the corpus callosum are rare diseases mainly affecting male population and broadly referred as L1 syndrome, caused by mutations in the L1CAM gene. In the present study 36 boys and a male fetus whose clinical features were consistent with L1 syndrome were analyzed by dHPLC assay and direct sequencing of L1CAM gene. Sequence analysis of the 14 different aberrant dHPLC elution profiles demonstrated that six of them were associated with already reported polymorphisms, four with previously described causative variants while the remaining four represented novel L1CAM mutations. The dHPLC method proposed identified eight (21 %) causative L1CAM mutations in our patients while direct sequencing failed to detect any variation in patients negative to dHPLC analysis. We conclude that the dHPLC assay represents a fast and efficient method for the screening of L1CAM mutations and that L1 syndrome should be considered in the differential diagnosis of intellectual disability in children, especially when other signs such as hydrocephalus or adducted thumbs are present.     

大鼠睾丸特异表达基因Ube1的分离鉴定及生物学特征

本研究采用抑制性消减杂交(suppression subtracfive hybridization, SSH)和cDNA快速扩增(rapid amplification of cDNA ends, RACE)技术从大鼠A型精原细胞和粗线期精母细胞中成功克隆出大鼠泛素激活酶(ubiquitin-activating enzyme)基因Ube1 (GenBank登录号EF690356).该基因序列全长3433 bp,其中开放阅读框有3171 bp,编码一个含1057个氨基酸的蛋白质.Blast比对显示,Ube1与小鼠泛素激活酶基因Ubely1的同源性为93%,与人泛素激活酶基因UBE1的同源性为82%.Ube1基因编码的蛋白质含泛素激活酶信号位点和泛素激活酶活化位点,这些位点也存在于人类和小鼠的泛素激活酶1中.RT-PCR分析显示,Ube1在睾丸中大量表达,而在心、肝、脾、肺、肾、肌肉、脑、卵巢中没有表达.荧光定量PCR分析不同生精细胞中Ube1的表达,显示Ube1在A型精原细胞中大量表达,在粗线期精母细胞、圆形精子细胞和支持细胞中微弱表达.以上结果提示,Ube1是大鼠睾丸特异表达基因,可能通过参与泛素/蛋白酶体途径来影响精子发生.     

Identification and characterization of TSAP, a novel gene specifically expressed in testis during spermatogenesis

Through in silico screens, we have identified many previously uncharacterized genes that display similar expression patterns as the mouse Dazl gene, a germ line-specific marker. Here, we report the identification and characterization of one of these novel genes. TSAP gene encodes a protein with 350 amino acids and contains five ankyrin repeats and a PEST sequence motif. Furthermore, we have generated an anti-TSAP antibody and have used three different approaches (RT-PCR, in situ hybridization, and immunohistochemistry) to investigate the expression profiles of TSAP mRNAs and proteins. TSAP is specifically expressed in testis, but not in other tissues such as ovary. Within the testis, TSAP is detected 10 days after birth and is mainly expressed in spermatocytes (ST) and later stage of germ cells, but not in spermatogonia (SG) or sertoli cells. Therefore, TSAP protein likely plays a role in spermatogenesis.     

SPAG4L在人类睾丸中的表达研究

目的:观察人类睾丸新基因SPAG4L在人类不同发育阶段睾丸及隐睾中的表达,为了解该基因在精子发生中的功能奠定基础;方法:收集流产胎儿、成年人、老年人及隐睾患者的睾丸组织,应用RT-PCR和组织原位杂交技术检测SPAG4L mRNA的表达;结果:RT-PCR和组织原位杂交技术检测结果发现,SPAG4L在胎儿睾丸中几乎检测不到,在成年及老年男性睾丸中均有高表达,主要在精母细胞和圆形精子细胞中表达;在隐睾患者的睾丸中,精母细胞大量凋亡,SPAG4L表达明显下调;结论:SPAG4L主要在精子发生减数分裂阶段表达,受生长发育调控,提示该基因可能在精子发生减数分裂阶段发挥着重要的生理功能.     

Identification of the human papilloma virus-1a E4 gene products.

Antibodies prepared against a human papilloma virus-1 (HPV-1) E4/beta-galactosidase fusion protein identified several polypeptides in HPV-1, but not HPV-2 or 4, induced papillomas. The major E4 protein, that represented up to 30% of total cellular protein, was a 16/17-K doublet which was purified by column chromatography and analysed for amino acid content. A peptide derived by chymotryptic digestion was purified by h.p.l.c. and subjected to amino acid sequencing. The unique sequence obtained, Gly-His-Pro-Asp-Leu-Ser-Leu, identified the 16/17-K doublet as a product of the HPV-1 E4 gene region. Antibodies to both the E4/beta-galactosidase fusion protein and the 16/17-K doublet identified two smaller polypeptides (10/11-K) which may represent spliced products of E4. We propose that the products of the HPV-1 E4 gene region are not classical DNA tumor virus early proteins and suggest that they play a role in virus maturation.     

A novel spermatogenesis-specific uPAR gene expressed in human and mouse testis

The urokinase receptor, uPAR, which binds to the urinary-type plasminogen activator, controls matrix degradation in the processes of tissue remodeling, cell migration, and invasion. In the present study, we found a new urokinase receptor gene that encodes a 249-amino acid putative protein. Northern blot analysis showed specific expression in the testis of this gene, which we named the spermatogenesis-related gene (SGRG). In situ hybridization revealed a strong expression signal for SGRG in spermatogonia, but not in spermatocytes. Therefore, we conjecture that SGRG may regulate spermatocyte migration through breakdown of extracellular matrix protein barriers in spermatogenesis. Since SGRG is specifically expressed in spermatogonia, it provides an attractive candidate for development of a contraceptive vaccine.