鼠精子发生时期差异表达基因的克隆(英文)

为了分离鼠精子发生时期表达的基因,本文采用mRNA差异显示法,以鼠的粗线期卵母细胞为对照,检测了出生后60天和16天鼠的睾丸。得到12个有差异的片段(Fig.1&Table 1)。克隆测序结果表明,其中5个与已知基因非常吻合,另外6个与一些未知功能的cDNA、ESTs有较高的同源性,只有1个与已知序列没有同源性。Northern杂交分析显示sp1和sp8主要在成年鼠睾丸表达(Fig.4B)。采用5RACE对sp1的cDNA进行了全长分析,该基因编码一个推测是高度磷酸化蛋白的541个氨基酸(Fig.2),其中包括一个核定位信号,无论在核苷酸水平上,还是在氨基酸水平上均没有明显的同源性,仅在2个蛋白区有少量同源氨基酸(Fig.3)。该基因在20-60天龄鼠的睾丸均有表达,并且具有很高的组织特异性只在睾丸里表达(Fig.4A)。因而,这个基因有可能参与减数分裂及其以后的整个过程。可以认为这是一个新基因。我们把它命名为peat (predominantly expressed in adult testis)。     

Crlz-1 Is Prominently Expressed in Spermatogonia and Sertoli Cells during Early Testis Development and in Spermatids during Late Spermatogenesis

The expression of the Crlz-1 gene in mouse testis, where it was found to be expressed most highly among the tested mouse organs, was analyzed spatiotemporally by employing RT-PCR and in situ hybridization techniques with the aid of immunohistochemistry and/or immunofluorescence methods. In 1-week-old neonatal testis, Crlz-1 was strongly expressed in the spermatogonia and Sertoli cells in its seminiferous cord. In 2- to 3-week-old prepubertal testis, where Sertoli cells cease to proliferate, Crlz-1 expression dropped and remained weakly at the rim layer of seminiferous cords and/or tubules, where spermatogonia are present. In the adult testis at 12 weeks after birth, Crlz-1 was expressed mainly in the spermatids near the lumen of seminiferous tubules. In a further in situ hybridization of Crlz-1 in the 12-week-old adult testis with hematoxylin nuclear counterstaining, Crlz-1 was mainly expressed at step 16 of spermatids between stages VII and VIII of seminiferous tubules as well as in their residual bodies at stage IX of seminiferous tubules.     

Polycomb基因家族在大鼠精子发生过程中的表达

目的检测大鼠精子发生不同阶段细胞中Polycomb-group（Pc-G）家族在mRNA水平上表达是否有差异。方法提纯大鼠精子发生过程中的精原细胞、精母细胞、圆形精子细胞以及支持细胞,用荧光定量PCR方法检测Pc-G家族基因mRNA表达量。结果Pc-G基因家族中Ezh2、Eed、Bmi-1在精子发生中后期高表达;在各生精细胞中,YY1基因表达量低于支持细胞。结论Pc-G基因家族在精子发生各阶段细胞中特征性表达,与精子发生具有相关性,可能对精子发生分化和维持遗传稳定性都有重要的作用。     

The Arabidopsis 1-Aminocyclopropane-1-Carboxylate Synthase Gene 1 Is Expressed during Early Development

The temporal and spatial expression of one member of the Arabidopsis 1-aminocyclopropane-1-carboxylate (ACC) synthase gene family (ACS1) was analyzed using a promoter-[beta]-glucuronidase fusion. The expression of ACS1 is under developmental control both in shoot and root. High expression was observed in young tissues and was switched off in mature tissues. ACS1 promoter activity was strongly correlated with lateral root formation. Dark-grown seedlings exhibited a different expression pattern from light-grown ones. The ACC content and the in vivo activity of ACC oxidase were determined. ACC content correlated with ACS1 gene activity. ACC oxidase activity was demonstrated in young Arabidopsis seedlings. Thus, the ACC formed can be converted into ethylene. In addition, ethylene production of immature leaves was fourfold higher compared to that of mature leaves. The possible involvement of ACS1 in influencing plant growth and development is discussed.     

NYD-SP15: A Novel Gene Potentially Involved in Regulating Testicular Development and Spermatogenesis

By hybridizing human adult testis cDNA microarrays with human adult and embryo testis cDNA probes, we identified a novel human testis gene, NYD-SP15. NYD-SP15 expression was 3.26-fold higher in adult than in fetal testis; however, there was almost no NYD-SP15 expression in the sperm. NYD-SP15 comprises 3364 base pairs, including a 1545 bp open reading frame encoding a 514 amino acid protein possessing 89% sequence identity with the mouse testis homologous protein. NYD-SP15 is located on human chromosome 13q14.2. The deduced structure of the protein contains two dCMP_cyt_deam domains, indicating a potential functional role for zinc ion binding. The gene is expressed variably in a wide range of tissues, with high expression levels in the testis. Sequence analysis revealed that NYD-SP15 is not a highly conserved protein, with its distribution in high-level species such as vertebrates including Homo, Mus, Rattus, and Canis. The results of semiquantitative polymerase chain reaction in mouse testis representing different developmental stages indicate that NYD-SP15 expression was developmentally regulated. These results suggest the putative NYD-SP15 protein may play an important role in testicular development and spermatogenesis and may be an important factor governing male infertility. These authors contributed equally to this work     

A Novel Zebrafish Gene Expressed Specifically in the Photoreceptor Cells of the Retina

We have identified and characterized a novel protein from adult zebrafish retina, which we named ES1. Database search revealed that the ES1 gene has significant similarity to two genes with unknown functions: theEscherichia colisigma cross-reacting protein 27a (scrp27a) and the human KNP-I/GT335.In situhybridization and immunohistochemistry experiments showed that both ES1 mRNA and protein are expressed specifically in adult photoreceptor cells. ES1 seems to be a cytoplasmic protein. An ES1-like antigen was also detected in photoreceptor cells of goldfish with anti-ES1 antibodies. The retina specific expression and the evolutionary conservation suggest that ES1 protein may be important for maintaining normal retina structure and function.     

A Brassica Self-Incompatibility Gene Is Expressed in the Stylar Transmitting Tissue of Transgenic Tobacco

Tobacco was transformed with a gene coding for an S-locus-specific glycoprotein of Brassica oleracea. The resulting transgenic plants showed tissue-specific and developmentally regulated expression of the introduced gene. Immunolocalization experiments showed that the Brassica gene was expressed in the stylar transmitting tissue of the transgenic plants. The pattern of expression of the introduced gene was more similar to that of the S-associated genes of Nicotiana alata than to expression in Brassica. Self-incompatibility was not conferred by the introduced gene.     

Molecular Cloning of a Novel Human Acid Phosphatase Gene (ACPT) That Is Highly Expressed in the Testis

Acid phosphatases are enzymes capable of hydrolyzing orthophosphoric acid esters in an acid medium. Prostatic acid phosphatase has served as a tumor marker for metastatic prostate cancer for many years. We have cloned a new human acid phosphatase gene (named testicular acid phosphatase, ACPT), which is expressed mainly in testis and to a lower extent in the prostate, trachea, and other tissues. This gene maps to chromosome 19q13.4, in an area that harbors many cancer-related genes. The testicular acid phosphatase gene is composed of 11 exons, and the protein is predicted to have a luminal domain, a transmembrane domain, and a cytoplasmic domain. The N-terminal end of the protein encodes a signal peptide. The protein has approximately 50% homology with both the prostatic and the lysosomal acid phosphatases, and the position of the cysteine residues, the N-glycosylation sites, and the histidine catalytic site are conserved among the three proteins. The testicular acid phosphatase gene is up-regulated by androgens and is down-regulated by estrogens in the prostate cancer cell line LNCaP. Our preliminary results indicate that this gene exhibits a lower level of expression in testicular cancer tissues than in their normal counterparts.     

Chromodomain Helicase Binding Protein 8 (Chd8) Is a Novel A-Kinase Anchoring Protein Expressed during Rat Cardiac Development

A-kinase anchoring proteins (AKAPs) bind the regulatory subunits of protein kinase A (PKA) and localize the holoenzyme to discrete signaling microdomains in multiple subcellular compartments. Despite emerging evidence for a nuclear pool of PKA that rapidly responds to activation of the PKA signaling cascade, only a few AKAPs have been identified that localize to the nucleus. Here we show a PKA-binding domain in the amino terminus of Chd8, and demonstrate subcellular colocalization of Chd8 with RII. RII overlay and immunoprecipitation assays demonstrate binding between Chd8-S and RIIα. Binding is abrogated upon dephosphorylation of RIIα. By immunofluorescence, we identified nuclear and perinuclear pools of Chd8 in HeLa cells and rat neonatal cardiomyocytes. We also show high levels of Chd8 mRNA in RNA extracted from post-natal rat hearts. These data add Chd8 to the short list of known nuclear AKAPs, and implicate a function for Chd8 in post-natal rat cardiac development.